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    2009 ncdd-csf-technical-manual-vol-i-study-design-guidelines 2009 ncdd-csf-technical-manual-vol-i-study-design-guidelines Document Transcript

    • Royal Government of CambodiaNational Committee for Sub-National Democratic DevelopmentCommune/Sangkat Fund Technical Manual Volume IStudy and Design Guidelines 2009
    • VOLUME I:STUDY AND DESIGN GUIDELINES
    • CONTENTSPREFACE ...................................................................................................................... ivList of Abbreviations ..................................................................................................... vPART 1: INTRODUCTION .............................................................................................. 11 Introduction ......................................................................................................... 21.1 Preamble .......................................................................................................................... 21.2 Commune/Sangkat Fund Technical Manual ................................................................. 21.3 Scope of Technical Manual ............................................................................................ 41.4 Contents of Technical Manual ....................................................................................... 4PART 2: TECHNICAL FORMS ....................................................................................... 62 Technical Forms ................................................................................................. 72.1 Introduction ..................................................................................................................... 72.2 Technical Forms are Mandatory .................................................................................... 82.3 Differences between Technical Forms ......................................................................... 82.4 Getting Design Guidance ............................................................................................... 82.5 Example Technical Forms.............................................................................................. 82.6 Transportation Infrastructure, Group Output Code 1010000 ...................................... 82.6.1 Form T11 Transport: Roads ........................................................................................... 92.6.2 Form T12 Transport: Structures .................................................................................. 172.7 Irrigation System, Group Output Code 1020000 ........................................................ 232.7.1 Form T21 Irrigation: Project ......................................................................................... 232.7.2 Form T22 Irrigation: Earthwork ................................................................................... 332.7.3 Form T23 Irrigation: Structure ..................................................................................... 432.8 Water Supply, Group Output Code 1030000 .............................................................. 512.8.1 Form T31 Water Supply ................................................................................................ 512.9 Education Facility, Group Output Code 1040000 ....................................................... 622.9.1 Form T41 Education Facility ........................................................................................ 622.10 Health, Group Output Code 1050000 .......................................................................... 702.10.1 Form T51 Health ........................................................................................................ 702.11 Sanitation, Group Output Code 1100000 .................................................................... 772.11.1 Form T101 Sanitation ............................................................................................... 77PART 3: TEMPLATE DESIGNS FOR LOCAL INFRASTRUCTURE ........................... 863 Template Designs for Local Infrastructure ..................................................... 873.1 Background ................................................................................................................... 873.2 NCDD Templates ........................................................................................................... 873.3 Available Templates ..................................................................................................... 873.4 How to Read and Use the Drawings ............................................................................ 87 I-i
    • 3.4.1 Size ................................................................................................................................. 873.4.2 Drawing scales .............................................................................................................. 883.4.3 Dimensions ................................................................................................................... 883.4.4 Revisions ....................................................................................................................... 883.4.5 Variable dimensions ..................................................................................................... 883.4.6 How to read the steel details and the steel schedule ................................................ 883.5 AutoCAD Standards ..................................................................................................... 893.5.1 AutoCAD Version .......................................................................................................... 903.5.2 General settings ............................................................................................................ 903.5.3 AutoCAD file name ....................................................................................................... 903.5.4 Drawing number ........................................................................................................... 903.5.5 Paper size ...................................................................................................................... 913.5.6 Pen assignment for plotting ........................................................................................ 913.5.7 Layer definition ............................................................................................................. 913.5.8 Text style and fonts ...................................................................................................... 923.5.9 Line types / widths ........................................................................................................ 933.5.10 Hatch .......................................................................................................................... 933.5.11 Dimensions................................................................................................................ 933.5.12 Blocks ........................................................................................................................ 943.5.13 External references (x-ref) ....................................................................................... 943.5.14 Viewports ................................................................................................................... 943.5.15 Plotting....................................................................................................................... 94PART 4: MATERIALS, QUANTITIES AND COSTS .................................................... 954 Materials, Quantities & Costs .......................................................................... 964.1 Project Cost Estimation ............................................................................................... 964.2 Tables of Quantities and Labor Costs ........................................................................ 964.3 Net Quantities ............................................................................................................... 964.4 Cost Estimation Using the Project Generator ............................................................ 97PART 5: STUDY AND DESIGN GUIDELINES ........................................................... 1095 Study and Design Guidelines ........................................................................ 1105.1 Introduction ................................................................................................................. 1105.1.1 Limitations ................................................................................................................... 1105.1.2 Using the design guidance ........................................................................................ 1105.2 Transport Infrastructure: Group 101 ......................................................................... 1115.2.1 Sub-Group 10101 and 10102: Roads: Form T11 ...................................................... 1115.2.2 Sub-Group 10103 to 10108: Road Structures: Form T12 ........................................ 1175.3 Irrigation System: Group 102 .................................................................................... 1315.3.1 Irrigation Project: Form T21 ....................................................................................... 1315.3.2 Irrigation Earthwork: Form T22 ................................................................................. 1345.3.3 Irrigation structure: Form T23 ................................................................................... 1395.4 Water Supply: Group 103 ........................................................................................... 1405.5 Education Facilities: Group 104 ................................................................................ 1485.6 Health Facilities: Group 105 ...................................................................................... 1495.7 Market Construction: Group 106 ............................................................................... 1505.8 Crop Storage and Processing: Group 107 ............................................................... 1505.9 Social Infrastructure: Group 108 ............................................................................... 150 I-ii
    • 5.10 Energy: Group 109 ...................................................................................................... 1505.11 Sanitation: Group 110................................................................................................. 1505.11.1 Latrines .................................................................................................................... 1515.11.2 Waste water and solid waste ................................................................................. 1515.11.3 Drainage ................................................................................................................... 1515.12 Flood Protection Structures: Group 111 .................................................................. 153ANNEX 1: TECHNICAL FORMS ................................................................................ 154Technical Form T11 – Transport: Roads .............................................................................. 155Technical Form T12 – Transport: Structures ....................................................................... 159Technical Form T21 – Irrigation: Project .............................................................................. 163Technical Form T22 – Irrigation: Earthwork......................................................................... 167Technical Form T23 – Irrigation: Structure .......................................................................... 172Technical Form T31 – Water Supply ..................................................................................... 175Technical Form T41 – Education Facility ............................................................................. 179Technical Form T51 – Health ................................................................................................. 181Technical Form T101 – Sanitation......................................................................................... 183 I-iii
    • PREFACEThis book is the first volume of Commune Sangkat Fund Technical Manual produced by theNational Committee for Sub-National Democratic Development (NCDD) with the help of theMinistry of Rural Development (MRD), the Ministry of Water Resources and Meteorology(MoWRAM), and others. Commune Sangkat Fund Technical Manual consists of 7 parts whichare divided into 3 volumes as the followings:x Volume I : Study and Design Guidelinesx Volume II : Specifications for Construction Materials and Worksx Volume III : Contract SupervisionThis first volume states mainly the study and design guidelines for the implementation of small-scale infrastructure projects financed by Commune Sangkat Fund. It comprises 5 parts among 7parts of Commune Sangkat technical manual as the followings:x Part 1 : Introductionx Part 2 : Technical Formsx Part 3 : Template Designs for Local Infrastructurex Part 4 : Materials, Quantities and Costsx Part 5 : Study and Design GuidelinesFor part 6 which instructs on specifications for construction materials and works is in Volume II;while the final part- part 7 is in volume III which explains about contract supervion by the use ofConstruction Check Lists. I-iv
    • List of AbbreviationsADT Average Daily TrafficApplet A spreadsheet to calculate Design flow and structure sizeAASHTO American Association for State Highway and Transportation OfficialBOQ Bill of FQuantityCBR California Bearing RatioCSO Civil Society OrganizationC/S Commune/SangkatCIP Community Investment ProgramDFT District Facilitation TeamDCP Dynamic Cone Penetration TestDoLA Department of Local AdministrationDBST Double Bituminous Surface TreatmentEA Environmental AssessmentEIA Environmental Impact AssessmentEMP Environmental Management PlanExCom Executive CommitteeFWUC Farmer Water User CommitteeGPS Global Positioning SystemGTFM Generalised Tropical Flood ModelHFWL High Flood Water LevelIO International OrganizationLAU Local Administration UnitNGO Non-Governmental OrganizationMEF Ministry of Economy and FinanceM&E Monitoring and EvaluationMoI Ministry of InteriorMRD Ministry of Rural DevelopmentNCDD National Committee for Sub-National Democratic DevelopmentO&M Operation & MaintenancePBC Planning and Budgeting CommitteePCU Passenger Car UnitPFT Provincial Facilitation TeamPIM Project Implementation ManualPMC Project Management CommitteePRDC Provincial Rural Development CommitteePSDD Project Support for Decentralization and DeconcentrationPDoWRAM Provincial Department of Water Resource and MeteorologySBST Single Bituminous Surface TreatmentST 1 Sub-Tertiary 1ST 2 Sub-Tertiary 2ST 3 Sub-Tertiary 3T TertiaryTSO Technical Support OfficerTSU Technical Support UnitTRRL Transport Road Research Laboratory (DCP Model) I-v
    • PART 1: INTRODUCTION I-1
    • Part 1: Introduction1 Introduction1.1 PreambleThe principal and first order document for implementation of projects under theCommune/Sangkat Fund (C/S Fund) is the C/S Fund Project Implementation Manual (PIM).The C/S Fund Technical Manual (this document) is a second order document dealing only withtechnical aspects of C/S Fund infrastructure projects and particularly the interface with the C/SFund Project Generator software developed for infrastructure projects. C/S Fund serviceprojects are not dealt with by the Technical Manual.If there is a conflict between the C/S Technical Manual/Project Generator and the PIM then thePIM takes precedence.1.2 Commune/Sangkat Fund Technical ManualThe C/S Fund Technical Manual is for the design and construction of small-scale infrastructureprojects financed by the Fund. The Technical Manual is used with an interactive softwarepackage called the C/S Fund Project Generator.It has been produced by the National Committee for Sub-National Democratic Development(NCDD) with the help of the Ministry of Rural Development (MRD), the Ministry of WaterResources and Meteorology (MoWRAM), and others.It originated as the Seila Technical Manual and the accompanying interactive software packagecalled the Seila Template Program developed between 2001 – 2006. The Seila material andprocedures were used and evolved over several years with some success and were taken overby NCDD. The many strong features of the approach were recognized but there were someproblems also. In particular the Template designs and program were somewhat inflexible and itwas difficult to update or add new designs. Also the many forms and procedures required bythe Project Implementation Manual (PIM) although they provided a strong system in themselveswere demanding on time and resources in the provinces; and had to be completed within a veryshort time window in the annual project cycle. Consequently many of the forms were oftenincomplete and seldom properly checked prior to approval. In addition the constructionsupervision was inadequate with the result that it was common for infrastructure works to be ofpoor quality and not completed to the full dimensions.The new manual differs in several ways: x The core ‘template program’ function has been retained but rewritten on a flexible software platform; it incorporates standard design drawings (prepared in AutoCAD but saved and accessed in PDF format) linked to spreadsheets which calculate quantities and costs according to variable dimensions. x The concept of checklist-type feasibility study PIM forms from the Seila Template process have been upgrade to interactive ‘Technical Forms’ built into the Project Generator software in combination with the Template program component. Hence the forms call in the outputs of the template program automatically by use of links and dropdown menus allowing rapid and quality assured assembly of a project portfolio. x The new technical forms in “ project generator ” provide design guidance where technical design is required. The user must answer simple questions by either filling data or choosing answer from multiple choice answers.In some technical forms, advice on type and dimensions of infrastructure will be provided in order to choose project output. To obtain the advice, you need to do some calculation by using several small Excel programs called “Applet”. The programs are interactive, the user can change some design requirements, or in some cases vary the design criteria used, until an acceptable design is produced. The user can choose the final design choice which can be less than recommended if there is good reason.Study and Design Guidelines I-2
    • Part 1: Introduction x For construction supervision the Technical Guidelines incorporate an updated and expanded version of construction checklist forms developed by MRD. x The Project Generator can be expanded to cover other requirements of the PIM.This Technical Manual is distributed to all Provincial Departments of Rural Development(PDRD), and to contractors working on C/S Fund infrastructure projects. It is also available toother organisations working in rural infrastructure.The C/S Fund Technical Manual is primarily intended as a resource to be used in design ofinfrastructure projects of the Commune and Sangkat Councils. Most of the projects are smalland simple. There are many different projects with similar outputs. For example, in 2002 theCommune Councils constructed about 1200 road culverts and about 1100 wells.The drawings in the C/S Fund Technical Manual can be used for about 90% of all theinfrastructure project outputs implemented by the Commune Councils.Most of the drawings are not new, they are generally based on designs in current use by lineministries, in some cases simplified or condensed so that they can be used by small workscontractors. Other designs have been taken from development sector literature and adaptedalways with the emphasis on suitability for use in contemporary rural communities in Cambodia.Almost all the drawings in the original Seila Manual have been used on many successfulprojects already.Most Commune and Sangkat projects will be constructed by small contractors who do not havehigh level technical skills, or a lot of equipment. The drawings in the C/S Fund TechnicalManual can help the Communes and the contractors to achieve good results in the followingways: x The drawings are available in Khmer and English languages; x The drawings are easy to read, by people who do not have high technical education (If you think that the drawings are not easy to read, please complain and we will try to improve them!); x The project outputs shown in the drawings are easy to construct, without a lot of special equipment; x The designs do not need a very high quality of construction technique, to achieve a successful project. For example, concrete structures built using the designs will be strong enough, even if the quality of the concrete is not very good.When the Commune Council implements a project, they must follow technical guidelines fromthe Ministry that is responsible for the sector. For example, road projects should followguidelines from the Ministry of Rural Development, and irrigation projects should followguidelines of the Ministry of Water Resources and Meteorology.Because the Ministries have helped to produce the Technical Manual (and the earlier SeilaTechnical Manual), the drawings in the Manual follow Ministry guidelines. If the Communechooses a drawing from the Manual for their project, they know that the drawing follows theguidelines. However, the Commune can choose to use a different drawing (one that is not inthe Manual) if they prefer.The drawings show technical designs for project outputs. Before choosing a drawing for theproject outputs, the project designer must decide what types of outputs are needed, how big theoutputs must be and where the outputs must be. However, provided that the basic field data iscollected the interactive Technical Forms in the Project Generator will provide most of theinformation required to assemble the design file.Study and Design Guidelines I-3
    • Part 1: Introduction1.3 Scope of Technical Manual It is essential for TSO’s to also make field visits to: ™ Assess initial purpose of the project ™ Re-check overall objective and revise if project differs from its initial purpose ™ Facilitate in procuring external engineering services if needed1.4 Contents of Technical ManualThe C/S Fund Technical Manual has the following parts. Part 1: Introduction x This section which includes general instructions on the use of the Technical Manual Part 2: Technical Forms x This describes the filling of Technical Forms for infrastructure projects. (all other aspects of project preparation and clearance are described by the PIM). Filled examples are included for the Technical Forms currently loaded to the Project Generator. A full set of unfilled forms is at Annex 1. Part 3: Template Designs for Local x This describes how to understand and use Infrastructure the template designs already loaded into the Project Generator, and how to prepare new template designs. Part 4: Materials, Quantities & Costs x This presents the tables of materials and quantities that the PIM requires to be used for estimation of project costs. It also includes explanation and an example of the quantity tables associated with each template design loaded to the generator.Study and Design Guidelines I-4
    • Part 1: Introduction Part 5: Study and Design Guidelines x This section provides basic guidance on the technical aspects of study and design such as slope stability, hydrological and hydraulic considerations, choice of materials, etc. Filling the Technical Forms guides most of the design decisions and small ‘applet’ programs are called for simple design calculations. The design guidance is for about 90% of projects, the remaining 10%, because they are unique or have special circumstance will require ‘specialist design input’. Part 6: Specifications for Construction x This provides explanations and instruction Materials and Works on use of the specifications use a tabular format. This is followed by revised and expanded tabulated specifications. Part 7: Contract Supervision x This section explains the use of Construction Check Lists. Examples of filled check lists for two types of project are included. The full set of 32 check lists is at Annex 3.Study and Design Guidelines I-5
    • Part 2: Technical Forms PART 2: TECHNICAL FORMSStudy and Design Guidelines I-6
    • Part 2: Technical Forms2 Technical Forms2.1 IntroductionThis section describes how to comply with the requirements of the Project ImplementationManual (PIM) that for an infrastructure project the Technical Assistant prepares TechnicalInformation Forms. These forms are part of the core process of Project Preparation andTechnical Clearance.It is required that the Technical Assistant will assist the Project Management Committee tostudy the technical aspects of the project at the project site in close cooperation with the UserGroups and local community organizations to collect important and necessary information forfilling in the Project Information Form and Technical Information forms.The general information and technical information will be used to prepare the project design.The technical information is different according to the type of project. The different technicalforms are listed below: Infrastructure type Technical forms Code Description Form No. Project type Status of form1010000 Transportation Form T11 Transport: Roads Active in project Infrastructure generator Form T12 Transport: Structures Active in project generator1020000 Irrigation System Form T21 Irrigation: Project Active in project generator Form T22 Irrigation: Earthworks Active in project generator Form T23 Irrigation: Structures Active in project generator1030000 Water Supply Form T31 Water supply Active in project generator1040000 Education Form T41 Education Active in project Facilities generator1050000 Health Form T51 Health Active in project generator1060000 Market Form T61 Markets Form to be prepared Infrastructure1070000 Agriculture Form T71 Crop storage and Form to be prepared Infrastructure processing1080000 Social Form T81 Social infrastructure Form to be prepared Infrastructure1090000 Energy Form T91 Energy Form to be prepared1100000 Sanitation Form T101 Sanitation and Active in project drainage generator1110000 Flood Protection Form T111 Flood protection Form to be prepared Infrastructure structuresStudy and Design Guidelines I-7
    • Part 2: Technical FormsIt will be noted in the ‘status of form’ column that that there are “Forms to be prepared” for fiveof the infrastructure group. This is because at the time of writing this manual there are notemplates loaded into the Project Generator for these groups and very few such projects haveever been executed. This is anticipated to change in the future and it is intended to developadditional Technical Forms at that time when the precise requirements for the forms will beknown.2.2 Technical Forms are MandatoryIt is mandatory to complete in full the appropriate Technical Forms active in the ProjectGenerator. If the forms are not completed the Project Generator will not allow the projectpreparation and technical clearance process to proceed.2.3 Differences between Technical FormsEach Technical Form is structured differently depending on the types and numbers ofinfrastructure outputs for which it can be used and also the design processes necessary anddescribed in the design guidance.2.4 Getting Design GuidanceDesign guidance is provided at Part 6 of this manual.As far as is possible the Technical Forms incorporate the design guidance to advise the on therecommended output(s) and sizes where relevant. In some places there are MS Excel appletslinked to the forms that will do the calculations required. The limitations of the applets areexplained at Part 6 of this Manual.Care has been taken to take a realistic approach so that the advice will be correct most of thetime; and certainly a big improvement on past practice for some classes of infrastructure whichare often built without any consideration of the design needs.Design advice can still be overridden by the choosing a different output or size, which may befor a justified reason.2.5 Example Technical FormsThe remainder of this section describes the Technical Forms prepared to date and active in theProject Generator. There is a flow chart for each form illustrating the process of filling the formand where design calculations are made in the background.Each flow chart is followed by an example of that form output by the generator. Theappearance and content of the output depends on how the form was filled in the ProjectGenerator, the recommendations of the design guidance, and the final choices made for theinfrastructure output. Blank unfilled examples of the Technical Forms are at Annex 1.2.6 Transportation Infrastructure, Group Output Code 1010000There are two types of Technical Form for Transport Infrastructure: x Form T11 for roads x Form T12 for road structures.Generally only one Form T11 will be required provided the road width and surface type is thesame for the full length of the road. If it changes, e.g. because of increased traffic after a roadjunction, then more than one T11 might be filled.There must be one Form T12 for each road structure, e.g. if there is one 5 m concrete bridgeand three 1.0 m diameter pipe culverts then four T12 must be filled.Study and Design Guidelines I-8
    • Part 2: Technical Forms2.6.1 Form T11 Transport: RoadsFormsFirstly, use Applet T11 to get advices on suitable road surface options based by: x Entering into “Applet T11” Average Daily Traffic for existing road to determine MRD Class A or B and a total of 24 hour from classified traffic count at busiest part of road. x Entering DCP test results with GPS coordinates (Enter each DCP test result to Applet T11 and get the 20 percentile DCP strength).You will then get the advices on road type, surface and pavement thickness in the nextworksheet of Applet T11.After that you must create output according to the advises from the Applet, but you can chooseanother type of road surface and pavement thickness with appropriate reasons.Then go to technical form T11 to answer the questions on: x General project information – this fills automatically from information previously filled immediately when creating project. x Project location – enter the GPS coordinates of the start and finish of the road. x Type of roadworks required – option for five descriptions covering new, rehabilitated, and improvement by widening and/or upgraded surface. x Length of road – is entered manually x Road Classification – option for roads connecting district centre/communes/villages determines the MRD road classification and hence the minimum recommended road width. x Existing structures and new structures required – manual entry describing existing structures and anticipated number(s) and type(s) of new structure (the actual number, type and size of structure is decided using Form and Applet T12). x Type of existing road construction, its condition, and main cause of damage – a variety of questions and options describing the existing road, what wheeled traffic can pass in the wet and dry season, and the main cause of damage. x Materials available for road construction – a variety of questions about locally available road construction material, its quality, and haul distance to the site. x Foundation soils – description options for type of soil. x Proposed fill and cut slopes – Choose cut and fill slopes according to type of cut and fill material (this is used for quantity calculations).The form is completed by identifying responsibility for road maintenance.ExampleThe example shown is for 4.25 km improvement of a sub-tertiary road Type ST3.For this example the attachments generated by the Project Generator will be: 1. Template 1010102 drawings together with a profile pro-forma drawing in AutoCAD file used with Excel spreadsheet. 2. Spreadsheet for calculation of quantities to allow calculation of cost estimate (see Part 4 of this Technical Manual).Study and Design Guidelines I-9
    • Part 2: Technical Forms 3. Specification (see Part 6 of this Technical Manual) 4. One Form T12 for each structure identified as needed. 5. Construction check lists (see Part 7 of this Technical Manual).The flow chart and example Project Generator output follow below.Study and Design Guidelines I-10
    • Part 2: Technical Forms Flowchart for Technical Form T11Transport: Roads Traffic count ADT DCP Soils and Surfacing measurements 20 percentile DCP option(s) applet (advice) Create Output General information? Location? One Form T12 Road generated for each, classification? culvert, bridge and low-level crossing Form T12 List new each structure structures? Existing road construction? Condition of road? Main cause of damage? Materials available? Slopes? x Drawings Pavement type x Interactive and thickness? quantities S’SStudy and Design Guidelines I-11
    • Part 2: Technical FormsExample Project Generator print Form T11 Transport: RoadsForm T11 Transport: Road(Earth Road) Province : Kampong cham District : Sreisanthor S/C:Roseisrok Name of project : Repair of laterite road Code of S/C : 31411 Name of TSO : Seila Date of form preparation : 20-07-2009 1. Location: where is the earth road located within the Sangkat/Commune? * Describe this location It goes from Commune office to Som Roang Pagoda 2. Give the coordinates of GPS If there are many road segments which have the same condition width and pavement, give the coordinates of start points and end points of each segment. One row is for one segment. Start point Ending point X of GPS Y of GPS X of GPS Y of GPS 304010 1528230 308350 1528250 3. Type of road project: What kind of road work is required? New road construction Rehabilitate existing road, the same width and surface Improve and widen existing road, same surface Improve existing road, the same width upgraded surface Improve and widen existing road, upgrade surface. 4. Length of road: what is the length of the road (in kilometer)? 4250 5. Road classification: District to district road, Tertiary Road, (T Road), “6.0 m” District to Sangkat/Commune, Sub-tertiary Road Type 1, ( ST1 road) “6.0 m” Commune to commune road, Sub-tertiary Road Type 2, (ST2 road), “5.0m” Commune to village road, Sub-tertiary Road Type 3, (ST3 road), “4.0m” Village to village road, Sub-tertiary Road Type 3, (ST3 road), “4.0m” 6. Structures: are there existing structures? * If “yes” answer the following questions; if “no” skip to the next question.Study and Design Guidelines I-12
    • Part 2: Technical Forms Yes No 7. List number, description and dimensions of existing structures. 1. 1 small wooden bridge 2m span, 2. Three single pipe culverts 0.6m, 3. Carriageway above structure is 3m. 8. What new structures are required (number of each)? * fill a form T12 for each structure, number the structure in the table. Bridge culvert drift vented causeway 6 9. Type of existing road: is there existing path, car-track or road ? Yes No 10. Is the road on an embankment? Yes No 11. What is the width of the road? 3 12. Condition of road: what is the condition of the road? * first row for rainy season, the second row for dry season. Write “Can” or “Cannot”. Can: Can go, Cannot: Cannot go. Bicycle Motorcycle Motor- Koyun or Car or truck heavy truck remorque small truck for carrying for carrying for carrying people goods goods Can Can Can Can Cannot Cannot Can Can Can Can Can Cannot 13. Main cause of road damage: What causes the main damage? If “Something else”, answer the below question Flooding Ponding on the road surface Gully erosion from runoff from the surface Carts pulled by animals Small cars or pickup trucksStudy and Design Guidelines I-13
    • Part 2: Technical Forms Heavy trucks for carrying goods Something else (fill in the below question) 14. Others main causes: 15. Material availability for road construction. Remark: For the material which are required for road construction for the road type you have chosen skip to others questions! 16. Fill material from roadside borrow as dug: Meets specification requirements for Type 3 Fill Meets specification requirements for Type 1 Can meet specification for Type 3 material by mixing with imported material Can meet specification for Type 1 material by mixing with imported material Is unsuitable material (mud, organic soils or Peat). 17. Fill material from remote borrow pit: Meets specification requirements for Type 3 Fill Meets specification requirements for Type 1 18. Distance of borrow pit(s) from road (Km): 0.6 19. Source of sand: Borrow pit Stream bed 20. Distance from road (Km): 2 21. Source of gravel: Borrow pit Stream bed 22. Distance from road (Km): 2 23. Laterite Put “good”, “medium” or “poor” in the box of quality. Source distance of transportation (Km) quality Punley mountain 15 Poor 24. Type of stone from quarry * It the source is not borrow pit, please choose the answer below Hard metamorphic rock (granite, basalt, etc)Study and Design Guidelines I-14
    • Part 2: Technical Forms Limestone Sandstone 25. Type of stone for stream bed: * If the source is not stream bed, please choose the answer below Hard metamorphic rock (granite, basalt, etc) Limestone Sandstone 26. Water supply for earth work Source distance from road (Km) Domestic well 1 27. Road traffic: what are the proportion of the cars and trucks using the road? *Write in percentage. One place to another in Go from the commune to a Go from one place outside commune place outside the the commune to another commune or vice versa outside the commune 10% 90% 10% 28. the proportion of the cars and trucks using the road is: * Put it into percentage. Belong to people who live in the Belong to people who live outside the commune commune 48% 52% 29. Foundation soils: what kind of soil the structure stand on? * if “other”, mention in the following question: Soil that is very easily eroded Normal clay Sandy soils Gravels Earth with big stones in it Other. 30. For others soil kinds. 31. Side slope: Fill slope Vertical Horizontal 1 1Study and Design Guidelines I-15
    • Part 2: Technical Forms 32. Cut slope Vertical Horizontal 1 1 33. Choice of road: what is thickness of the pavement proposed? Surface (if applicable) Wearing course (if applicable) Base course (if applicable) Road base (if applicable) Sub base (if applicable) 34. Fill with the thickness of the road pavement choosing above: Road pavement thickness Laterite 300mm 35. Road maintenance: Does the commune have a Commune Road Sub-Committee? Yes No 36. Who is responsible for road maintenance? * if “Other” mention your answer in the question below. Ministry of Rural Development Sangkat/Commune Others 37. Write the person who is responsible for road maintenance if you choose “other” 38. Remark: You must upload “Applet” in which you entered your data to get the answers and the advices about road pavement. If you chose the road pavement that is not suitable less or more than recommendation from “Applet T11”, give your reason on Advice Tab.Study and Design Guidelines I-16
    • Part 2: Technical Forms2.6.2 Form T12 Transport: StructuresFormsFirstly, use Applet T12 to get advice on suitable type and size of drainage structure by: x Choosing the structure type envisaged, and changing it if it will be different from the recommended structure after filling hydrology and hydraulic data. x Filling hydrology and hydraulic data – details of the catchment draining to the structure if this can be determined (area, elevation of stream bed for slope, catchment soils, vegetation, land use and whether in a normal or high rainfall area).After that you must create output according to the advice from the Applet, but you can chooseanother type and size of drainage structure with appropriate reasons. (NOTE: It is stronglyrecommended not to select a smaller type and size of structure than advised).Then go to technical form T12 to answer the questions on: x General project information – this fills automatically from information previously filled immediately when creating project. x Project location – by entering the GPS coordinates of the structure the Project Generator creates a location plan. x Road classification and standard – the road classification, standard and width is entered manually, but if Form T12 has been generated by a Form T11 then the information is entered the same as the road form. x Scope of Works – requires information on the type, size and condition of the existing structure if there is one. x Materials available for structure construction – a variety of questions about available structure construction material, its quality, and haul distance to the site. x Foundation soils including results for DCP tests – description options for type of soil and DCP test results with GPS coordinates (Possibly enter each DCP test result to Applet T11 and get the 20 percentile DCP strength). x Required hydraulic capacity of structure – the design flow and velocity from Applet T12 or engineer.ExampleThe example shown is for one of the replacement pipe culverts on the previous example FormT11 for a road.For this example the attachments generated by the Project Generator will be: 1. Template drawing for output code 1010303 (see Part 3 of this Technical Manual) 2. Quantities table to allow calculation of cost estimate (see Part 4 of this Technical Manual). 3. Specification (see Part 6 of this Technical Manual). 4. Construction check lists (see Part 7 of this Technical Manual).The flow chart and example Project Generator output follow below.Study and Design Guidelines I-17
    • Part 2: Technical Forms Flowchart for Technical Form T12Transport: Structure Applet T12 calculates flow and selects Hydrological structure measurements? Recommended structure (advice) Create output of structure? General information? Form T11 (if Location? road project) Road classification? No Form T11 when project is single structure Existing structure information? Materials available? DCP Soils and measurements 20 percentile DCP Hydraulic capacity x Drawings of structure x QuantitiesStudy and Design Guidelines I-18
    • Part 2: Technical FormsExample Project Generator print Form T12 Transport: Structure Form T12 Transport : Road structure (Single pipe culvert 0.8m) Province : Kampong cham District : Sreisanthor S/C:Roseisrok Name of project : Repair of pipe culvert Code of S/C : 31411 Name of TSO : Seila Date of form preparation : 20-07-2009 1. Location: where is the structure located within the Sangkat/Commune? *Describe the location On Chhuk Stream 3km before Som Roang 2. Give the coordinates of the GPS. X of GPS Y of GPS 304010 1528230 3. Road Classification : * Road classification: T, ST1, ST2, or ST3. *Road standard: A or B Classification Road standard Width of pavement (m) ST3 B 4 4. Scope of work: is the structure part of a road project to be carried out at the same time or is the work for the structure only? A part of road project Structure only. 5. Is there an existing structure and if so what is its condition and description? If “Yes”, answer only the questions about the existing structure, then go to question 13. If “ No” go directly to question 13. Yes No 6. Describe of existing pipe culvert: * Material can be: Concrete, Clay, Plastic or steel. Headwalls can be: wood, masonry, mass concrete, Reinforced concrete, or none.Study and Design Guidelines I-19
    • Part 2: Technical Forms Number of diameter (m) Pipe material Headwalls Carriageway pipe width over culvert 3 0.6 Concrete Masonry 3 7. Describe the existing box culvert. * Headwall can be: Wood, masonry, mass concrete, reinforced concrete or none. Road slab can be: on wall or integrated with wall. Number of Width (m) Height Walls Road slab Carriage box width over culvert 8. Describe the existing concrete bridge. * Abutment material can be: wood, masonry, mass concrete, reinforced concrete, none. The piers can be: concrete on footing, concrete on piles. Deck material can be: wood or reinforced concrete. Number of Width of Height of Abutment Piers Deck Deck spans each each span material material carriageway span width(m) 9. Describe the existing steel bridge. * Steel bridge can be: Bailey, Vietnamese or others. Abutment material can be: wood, masonry, mass concrete, reinforced concrete or none. The piers can be: wood on footing, wood on piles, steel on footing, steel on piles, concrete on footing or concrete on piles. The deck can be: wood or steel plates. Type Number Width Height Abutment Piers Deck Deck of spans of each of each material material carriageway span span width(m) 10. Describe the existing wooden bridge. * Abutment material can be: wood, masonry, mass concrete, reinforced concrete, none. The piers can be: wood on footing, wood on piles. Deck material can be: wood or steel plate. Number of Width of Height of Abutment Piers Deck Deck spans each each span material material carriageway span width(m) 11. Describe the existing drift. *Road material can be: earth or laterite, stone, concrete or others. Width of ramp slope Difference in level road material carriageway crossing (m) between road on width (m) embankment and crossing (m) 12. Describe the existing vented causeway. Road material can be: earth or laterite, stone, concrete or others.Study and Design Guidelines I-20
    • Part 2: Technical Forms Width of ramp Difference in road carriageway Size of Size of crossing slope level between material width (m) opening opening (m) road on Width/Dia Height embankment and crossing (m) 13. What is the condition and cause damage of the structure? Good, no restriction on traffic (age of structure) Poor, most 4 wheel traffic can cross with care (bad design, material or construction) Bad, impassable to 4 wheel traffic (not suitable for current traffic) Collapsed and useless (damage by water or flood) 14. Available construction material: Part 1 * For construction material, fill with “Need” below type of material, then fill the source and distance. If “No need”, fill nothing. Source of fill type 3: borrow pit. Source of sands: borrow pit or stream bed. Source of gravel: borrow pit or stream bed. Type source distance sand source distance gravel source distance 3 fill (km) of (km) of (km) sands gravel borrow borrow borrow Need 0.1 Need 0 Need 2 pit pit pit 15. Part 2 * Source of stone: quarry or stream bed. Type of stone: hard metamorphic rocks (granite, basalt, etc). Stone Source of type of distance water source distance stone stone (km) supply for (km) concrete Need quarry Limestone 5 Need pump 0.5 from village 16. Foundation soils: What kind of soil is the structure founded on ? * if “others”, answers the following questions. Soil that is very easily eroded Normal clay Sandy soilStudy and Design Guidelines I-21
    • Part 2: Technical Forms Gravel Earth with big stone in it Others 17. Others, mention them. 18. Foundation strength of DCP (mm/blow) and location of each test. * Location: stream bed road centre line, stream bed upstream, stream bed downstream, left bank abutment, right bank abutment or others. DCP (mm/blow) location 23 Stream bed road centre line 15 Right bank abutment 35 Stream bed downstream 19. what is the 20 percentile DCP? 30.2 20. Hydrology and required hydraulic capacity of structure: did you use “Applet” to calculate the design flow, velocity, type and size of structure? * You can use “Applet T12” to determine the simple flow system, but for the complicated one, you have to find help from an engineer. Yes No 21. Maximum design flow (m3/s) from Applet or engineer is: * If you use Applet, write down the answer from form T12, worksheet GTFM:C32. 1.91 22. Velocity (m/s) which downstream structure can withstand is * if you use Applet, write down the answer from form T12, worksheet GTFM:C34 2.83 23. Remark: Upload “Applet” in which you fill the data to get the design flow, suitable structures and the velocity above. If you don’t use Applet to get the recommended structure, give your suitable reasons and upload the related documents that you use to determine design flow and velocity.Study and Design Guidelines I-22
    • Part 2: Technical Forms2.7 Irrigation System, Group Output Code 1020000There are three types of Technical Form for Irrigation Systems: x Form T21 for Irrigation: Project x Form T22 for Irrigation: Earthwork x Form T23 for Irrigation: Structure.Irrigation is generally the most complex and also usually the least successful infrastructureoutput supported by the C/S Fund.Form T21 is used to establish the requirements and constraints for irrigation. Even if theproposed output(s) are only an element of a larger irrigation system, it is strongly advised tocomplete a Form T21 to define the requirements for the C/S Fund investment. This form isrequired only one time for one irrigation system.Form T22 is used for irrigation earthworks; these can be dams or dykes, canals or drains.There must be a separate T22 for each earthwork, e.g. if a project comprises a dam and twocanals there must be three T22.Form T23 is for irrigation structures, e.g. spillway, head regulator, cross regulator, culvert, etc.There must be a separate T23 for each structure, e.g for the dam and canals above there maybe one spillway, one head regulator, two cross regulators and two culverts requiring six T23.2.7.1 Form T21 Irrigation: ProjectFormForm T21 requires answers for questions on: x General project information – this fills automatically from information previously filled immediately when creating project. x Project location – by entering the GPS coordinates of the structure (for irrigation projects choose an identifiable location, e.g. the dam across a stream). x Description of the project – manual entry summarising details of the project, if the output is part of a larger project, describe the larger project and the purpose the output will serve in relation to that project. x Farmer Water User Community (FWUC) – questions establishing whether there is an existing FWUC or whether farmers are prepare to form one. x Operation and maintenance responsibilities – manual entry for proposed operation and maintenance of the project (Note: failure to implement operation and maintenance procedures is a primary cause of failure of C/S Fund irrigation investments). x Irrigation system requirement – these questions establish what the community expects from the project, in both the dry and wet season. x Flooding – questions about flooding establish if, when and for how long the irrigated fields flood each year because this determines the periods and quantities of irrigation water required (remember that paddy rice is traditional grown on land that floods part of each year). x Existing irrigation systems – these questions establish the existing irrigation systems, their condition, whether they work and the perceived cause of problems. x Water resources – these questions establish where the irrigation water will come from, what periods of the year it is available, and how it will be delivered to the fields.Study and Design Guidelines I-23
    • Part 2: Technical Forms x Rainfall records – the nearest available rainfall record should be entered, each province should keep on file and update annually the rainfall records so that they are available for such purpose.At this stage use applet T21 to calculate the irrigation water requirement on a monthly basis; itis only necessary to enter the catchment area and chose the month of planting, and then copythe answer from Appet to the generator.If it is a reservoir project the applet determines: x reservoir volume required; x whether the reservoir is large enough; x water surplus/deficit downstream before project; x water surplus/ deficit downstream after project; x whether the reservoir has a negative impact on irrigation downstream; x the percentage reduction in water passed downstream; and x whether the impact downstream is acceptable.If it is a river intake project the applet determines: x whether there is enough water at the river intake; x water surplus/deficit downstream before project; x water surplus/deficit downstream after project; x whether the river intake has a negative impact on irrigation downstream; x the percentage reduction in water passed downstream; and x whether the impact downstream acceptable.It is probable that at the first attempt there will be too little water for the reservoir or river intakeproposal to work. The planting date, irrigated area and other design inputs can be adjusted tofind the best solution. Do not be surprised if a solution is not possible, especially in locations outside the Mekong floodplain. In many such places the landscape and rainfall patterns are such that reliable supplementary irrigation by traditional methods is impossible to achieve.A final choice is made confirming the ‘work proposed for the irrigation project’.ExampleThe example shown is for repair a Khmer Rouge earth dam, and canals for supplementaryirrigation of wet season rice. The work includes a new reservoir spillway and new headregulator using medium size water gate.For this example the attachments generated by the Project Generator will be: 1. 4No Form T22 (for one dam and three canals) 2. 7No Form T23 (for seven structures)The flow chart and example Project Generator output follow below.Study and Design Guidelines I-24
    • Part 2: Technical Forms Flowchart for Technical Form T21 General Irrigation: Project information? Location? FWUC? O&M? Irrigation requirement? Flooding Applet calculates irrigation water requirement, Existing reservoir volume, whether irrigation? reservoir or river intake will work, and whether impact downstream is Rainfall acceptable records Planting Irrigation water date? requirement Confirms whether reservoir or is viable One Form T22 or T23 generated for each, earthwork and structure Forms T22 Confirm each outputs earthwork Forms T23 each structureStudy and Design Guidelines I-25
    • Part 2: Technical FormsExample Project Generator print Form T21 Irrigation: ProjectForm T21 : Irrigation projet Province : Kampong cham District : Sreisanthor S/C:Roseisrok Name of project : Irrigation project at Bei village Code of S/C : 31411 Name of TSO : Seila Date of form preparation : 20-07-2009 1. Location: where is the project located within the Sangkat/Commune? Chongkoh village 2. Give the coordinate of GPS. X of GPS Y of GPS 304010 1528230 3. Project description: provide the description about the project including the proposed components and size of command area. Repair a Khmer Rouge earth dam, and canals for supplementary irrigation of wet season rice, include reservoir spillway and new head regulator using medium size water gate. 4. Farmer water user community: is there a farmer user community to support the project? * if you chose “No”, skip to question 7. Yes No 5. How many farmers (families) are members of the Community? 0 6. Have the farmers discussed together and agreed how they will pay the operation and maintenance costs of the project? Yes No 7. Operation and maintenance responsibilities: Who will be responsible to do the operation and maintenance? * if the scheme don’t need a pump, fill with “No need”.Study and Design Guidelines I-26
    • Part 2: Technical Forms Operate the Open and close Collect water Organize Solve disputes pump (if the water gates? user fees? maintenance between scheme needs work? farmers about a pump)? the water? No needed Gate keeper commune commune commune paid by council council council commune 8. Irrigation system requirement: what is the irrigated area in hectares? * Remark: if the project will be a part of a big irrigation project, only describe the part that will be affected by the project. Wet season dry season 100 0 9. What is the main type of crop that will be grown on the land? wet season dry season Rice Nothing 10. How much of the land that has enough water every year already? Wet season number of families dry season number of families 0 0 0 0 11. How much of the land that has enough water some years? Wet season number of families dry season number of families 50 40 0 0 12. How much of the land never has enough water at present? Wet season number of families dry season number of families 50 40 0 0 13. Total size of land and total number of families. * Totalize the size of wet season irrigated area, the number of families, the size of dry season irrigated area, the number of families. Wet season number of families dry season number of families 100 80 0 0 14. Flooding: Do the fields flood for some days each year? If “Yes”, answer the following questions, if “No”, skip to question 18.Study and Design Guidelines I-27
    • Part 2: Technical Forms Yes No 15. How long are the fields flooded (days)? 30 16. What is the flood depth during these days (m)? 0.15 17. What is the flood path, does the water flow concentrate is some places, describe and flow path(s) on map? The flood water comes over the fields from the north-west and stays a long time if the flood in the big to the south-east is big. 18. Existing irrigation system: is there and existing irrigation system? If “Yes”, answer the following question. If “No” skip to question 28. Yes No 19. When was the irrigation system built? If ‘1980 to 2000’ or ‘After 2000’, answer the following questions. If not, skip one question below. French era Sihanouk era Khmer Rouge era 1980 to 2000 After 2000. 20. Under what program or which donor paid for the project? 21. Does the system work? Working Working 50%Study and Design Guidelines I-28
    • Part 2: Technical Forms Works a little Not working 22. What are the main components of the system and what is their condition? River intake Reservoir Dam Spillways Large water gates Canals Small water gates and culverts 23. What is the condition of the irrigation project? Answer: Working, works a little, Not working or collapse for the main components of the system choosing above. Main components of the system condition Dam Not working Spillway Collapsed Big water gate Not working Canal A lot of damage Small water gate and culverts A lot of damage 24. How many months is water available? < 1 month 1 to 2 months 3 to 4 months 5 months 6 months > 6 monthsStudy and Design Guidelines I-29
    • Part 2: Technical Forms 25. What do you judge as the main problem with the existing irrigation system? There is no way of controlling the water, the water does not flow long enough to guarantee irrigation for rice, but for one month or longer the fields flood and there is too much water. 26. How can a new irrigation project overcome these problems? It will make the reservoir work, it will store water for later in the season and help control flooding. The canal will deliver water to the fields. 27. Do you have any other comments relevant to the proposed irrigation project? The community does not want to pay to form a FWUC, they say they can manage amongst themselves as they always have. This may be true but they will have problems later paying for large maintenance. They need some support on organisation, O&M and agricultural extension 28. Water resource: where will the water come from? River Reservoir Flood lake Canal 29. What is the water depth existing river, reservoir, lake or canal each month of the year and is the water stationary or flowing (include largest river flowing into or out of an existing reservoir)? Month depth (m) flowing, not flowing Jan 0 not flowing Feb 0 not flowing Mar 0 not flowing Apr 0 not flowing May 0 not flowing Jun 0.1 not flowing Jul 0.2 not flowing Aug 0.5 flowing Sept 0.1 flowing Oct 1.2 flowing Nov 0.9 flowing Dec 0.3 flowing 30. How will the water be delivered from the source to the distribution canals and fields? By pumpingStudy and Design Guidelines I-30
    • Part 2: Technical Forms By gravity 31. What is the difference in between the lowest water level at the source and the level of the fields (m)? * It is recommended to measure the difference in level with a survey instrument. 1.2 32. Irrigation water requirement: remark Use “Applet T21” to get “monthly water requirement for irrigation” and “gravity flow capacity per second”. 33. Works proposed for irrigation project: What are the main works items include size that will be repaired or newly constructed for the Irrigation Project? * For these following questions, answer only about situation and size of the structures chosen in this question. Reservoir Dam Spillways River weir or gate Head regulator Secondary canal Tertiary canal Canal, water gate or regulator Off-take Culverts 34. Reservoir works Repair or New Area (ha) Volume (m3) Repair 61 2200000 35. Dam worksStudy and Design Guidelines I-31
    • Part 2: Technical Forms * Fill the questionnaire form T22 Repair or New length (m) maximum height (m) Repair 800 3.5 36. Spillways works * Fill the questionnaire form T23 Repair or New length (m) drop (m) New ........ 4 37. River weir or gates height water raised Repair or New length (m) (m) 38. Head regulator works * Fill the questionnaire form T23 Repair or New Number gate size (m) New 1 0.6 39. Secondary canal works * Fill the questionnaire form T22 Repair or New Number Length (m) Repair 1 1500 40. Tertiary canal works * Fill the questionnaire form T22 Repair or New Number Total Length (m) Repair 1 1000 41. Canal water gates or regulators work * Fill the questionnaire form T23 Repair or new number New 1 42. Off-take works * Fill the questionnaire form T23 Repair or new number New 2 43. Culvert works * Fill the questionnaire form T23 Repair or new number size (m) with gate or not New 2 pipe culvert 0.8 With gate 44. Remark:Upload “Applet T21” that you’ve used into the Project Generator.Study and Design Guidelines I-32
    • Part 2: Technical Forms2.7.2 Form T22 Irrigation: EarthworkFormsFirstly, create output of dam, dyke, canal or drain then open Technical Form T22 which requiresanswers for questions on: x General project information – this fills automatically from information previously filled immediately when creating project. x Project location – enter the GPS coordinates of the start and finish of the earthwork. x Description of earthwork – select from choice of: dam, dyke, canal or drain, also select whether it is: new, improve, repair or maintenance. x Traffic use of earthwork – these questions determine whether the earthwork will be used as a track or road and therefore the required crest width and surfacing (note: it is common for embankments to serve a dual purpose as a public road and irrigation earthwork, this complicates maintenance because traffic damage can compromise irrigation operations. x Condition of existing dams and dykes – if the earthwork is a dam or dyke the condition must be entered manual and then a choice made from a list of common causes of damage. x Condition of existing canal and drain - if the earthwork is a canal and drain the condition must be entered manual and then a choice made from a list of common causes of damage. x Soils – select either the soils that will be use as (a) fill or (b) excavated for canals or drains. The advises whether the material is suitable as fill, safe fill or cut slopes, and whether canals or drains should be lined are provided next to the choices. x Availability of fill material – if the earthwork is a dam or dyke answers on the type, questions must be answered concerning the quality, location and distance from site of fill materials. x Design of dam or dyke – if the earthwork is a dam or dyke questions the design water level must be entered, the freeboard to calculate earthwork crest level, whether the earthwork is a road, the crest width and road surfacing, the upstream and downstream slopes, the method of slope protection for each slope, the class, thickness and filter requirements if rock riprap is used on the upstream slope. x Capacity of canal – Manually multiply the flow rate of canal to the irrigated areas. A default flow of 2 l/s/ha to the area of fields supplied is used but can be overridden. If the canal is supplied by pumps the hours pumped each day must be entered to calculate the pumping rate. x Capacity of drain – Manually multiply the flow rate of canal to the irrigated areas. A default flow of 3.5 l/s/ha to the area of fields drained is used but can be overridden. There are some questions to establish the concept for drainage (this is often overlooked and becomes another cause for failure). If the drain receives flow from a larger catchment area, details of this catchment must be entered in the same way as Form T12 Road: Structure in Applet T22 External catchment flow. The required flow capacity of the drain is the sum of the flow from the fields and that from a larger catchment area. x Hydraulic design of canal or drain – Having established the required capacity of the canal or drain the hydraulic calculations are the same and the same applet is used for both types of channel. It is necessary to enter the upstream and downstream bed levels, the side slopes and bed width, the freeboard. The calculation is iterative. A water depth is entered: if it is too small Applet T22 instructs to ‘Increase depth’; if it is too large theStudy and Design Guidelines I-33
    • Part 2: Technical Forms Applet instructs to ‘Decrease depth’; if the depth is correct (within a band of tolerance) the Applet prints ‘Depth OK’. The Applet then outputs the: minimum height of banks above bed level; width between tops of bank; and velocity of design flow. x Responsibility for operation and maintenance – these questions check whether there is a FWUC to take responsibility for design and maintenance and if not who will carry out design and maintenance.ExampleThe example shown is for rehabilitation of a Khmer Rouge canal downstream from a reservoir.But in this example the canal must also operate as a drain. Therefore it is necessary tocalculate the required capacities as both a canal and a drain; then use the larger of the twoflows for the hydraulic design of the channel.For this example the attachments generated by the Project Generator will be: 1. Template drawing(s) when available for chosen output code(s) (See Part 3 of this Technical Manual). 2. Spreadsheet for calculation of earthwork quantities (See Part 4 of this Technical Manual). 3. Quantities table to allow calculation of cost estimate (See Part 4 of this Technical Manual). 4. Specification (see Part 6 of this Technical Manual). 5. Construction check lists (see Part 7 of this Technical Manual).The flow chart and example Project Generator output follow below.Study and Design Guidelines I-34
    • Part 2: Technical Forms Flowchart for Technical Form T22 Create Irrigation: Earthwork Output? General information? Location? Description of earthwork Traffic use Condition of dams, dykes canals or drains? Soils? Design dam or dyke Calculation Capacity of Calculation manually in canal? manually in Generator Generator Capacity of drain? Applet calculates size of channel T22 External catchment flow.xls Hydraulic design T22-Design canal canal or drain or drain.xls Applet calculates flow from external catchment Responsibility for maintenance? x Drawings x Earthwork S’S x QuantitiesStudy and Design Guidelines I-35
    • Part 2: Technical FormsExample Project Generator print Form T22 Irrigation: EarthworkForm T22 Irrigation earthworks(Earth canal) Province : Kampong cham District : Sreisanthor S/C:Roseisrok Name of project : Repair earth canal Code of S/C : 31411 Name of TSO : Seila Date of form preparation : 20-07-2009 1. Location: where is the project located within the Sangkat/Commune? Location description: From the reservoir in Chongkoh village to rice field. 2. Provide the coordinate of GPS. * First is the starting point, the flow row is the ending point X of GPS Y of GPS 304010 1528030 304090 1528230 3. What type of earthwork is required? Build a new earthwork Improve the existing earthwork earthwork (e.g. raise or deepen, widen, add road surfacing) Repair a badly damage earthwork Periodic maintenance 4. Traffic use of earthwork: Is the earthwork used as a public road or for farm access? If “Not used” skip to question 11. Public road Farm access Not used 5. Has the earthwork ever had Laterite or any other kind of improved surface in the past? Yes No 6. Is there any Laterite or any other kind of surface on the earthwork now?Study and Design Guidelines I-36
    • Part 2: Technical Forms Yes No 7. What is the largest vehicle that uses the earthwork? Passenger car People walking Motorcycle Motor-remorque Bicycle Animal cart Light vehicle/van Koyun Medium truck (6 tyres) Heavy truck (6 tyres) Bus (>4 tyres) Mini-bus (4 tyres). 8. Approximately how many of these vehicles use the earthwork per day? * In PCU units, you can use Applet T11 to help your calculation of the number of vehicle. 0 9. According the traffic of vehicle above, what type of pavement is suitable for this earthwork? * if the number of vehicle is < 21 ‘Earth surface is satisfactory’. * if the number of vehicle is < 25 ‘Light Laterite surface is satisfactory’ * If number of vehicles is <100 ‘Medium Laterite surface is satisfactory’ * If number of vehicles is >100 ‘Too much traffic for Laterite surface consider other option’. 10. Condition of the existing dams or dykes and Canals or drains: describe the condition of the existing earthwork. The banks are eroded, breach and broken down so that water from the reservoir goes everywhere and often floods the fields.Study and Design Guidelines I-37
    • Part 2: Technical Forms 11. What causes most damage to the earthwork? * if “Other”, answer the question 12 Dam: traffic, people or animal Erosion from rain Wave damage from reservoir of flooding Flooding overtopping and breaching Flooding overtopping and breaching Water flow along channels at toe or structures Others Canal: too small for flow Blocked by weed Silted-up Bank erosion 12. If “Others” mention them. 13. Soils: What kind of soil is at the project site, (a) for use as fill, (b) for excavating canals and drains? Clay group, stable slope: upstream 1:2.00, downstream 1:1.75, Canal and drain 1:1.25 Sandy group, stable slope: upstream 1:2.50, downstream 1:2.00, Canal and drain 1:1.50 Silty soil, stable slope: upstream “not suitable”, downstream “not suitable”, Canal and drain 1:1.50 Dispersive clay, upstream “not suitable”, downstream “not suitable”, canal and drain : Line canal Organic soils, upstream “not suitable, downstream “not suitable”, canal and drain : Line canal. 14. Material for road construction: remark Skip the materias which are not chosen for road construction. 15. Fill material from borrow beside earth works.Study and Design Guidelines I-38
    • Part 2: Technical Forms Meets the specification requirement for type 3 fill Exceeds specification for Type 3 Fill with high clay content 16. Fill material from remote borrow pit * fill material can be 1. Meets the specification for type 3 fill, 2. Exceeds specification for type 3 fill with high clay content. Suitability, source (km). Suitability source (km) Exceeds specification for type 3 3 17. Sands * Source: borrow pit, stream bed. Source distance (km) 18. Gravel * Source: borrow pit, stream bed .Source distance (km) 19. Laterite * Source: borrow pit, stream bed. Quality: Good, medium or poor. Source Quality distance (km) 20. Stone * Source: quarry, stream bed. Type: granite, basalt, limestone… Source type distance (km) 21. Water supply for earthwork Source distance (km) Bottom of reservoir 1 22. Design of dam and dyke: What is reservoir full supply level at dam or flood levels at dyke (m)? 23. What freeboard will be allowed (m)? * You can get the values of freeboard from PIM. 24. Dam or dyke crests level (before any road surface is added), (m). 25. Will the dam or dyke be used as a road? 26. What is the crest width? 27. Will the crest be surfaced? If “Others”, answer the following question. Not surfacedStudy and Design Guidelines I-39
    • Part 2: Technical Forms Laterite Others 28. Others, mention them. 29. If laterite, what is the thickness of laterite (mm) ? 30. What will be the upstream slope (see advice in question 13)? 31. What will be the downstream slope (see advice in question 13)? 32. What slope protect will be provided to the upstream slope? * If not “Rock riprap”, skip the question 34 to 36. None Grass Rock riprap Others 33. If “Others”, mention them. 34. If “Rock riprap”, What class of riprap (Class A suitable for small reservoirs)? Class A Class B Class C Class D 35. What thickness of riprap in millimeters (300 mm minimum for Class A)? 36. What filter will be placed below riprap? 150mm gravel 50mm sands over geotextile 37. What slope protect will be provided to the downstream slope? None Grass 38. Capacity of canal: Will the canal be irrigated continuously (24 hours) by gravity or by pumping? If “Gravity”, answer the question 40, then skip the question 41. If “Pumping”, skip the question 41, then answer the question 41.Study and Design Guidelines I-40
    • Part 2: Technical Forms Gravity Pumping 39. Required flow capacity (gravity). * the design peak flow rate : 2l/s/h or another higher flow rate. * flow capacity (l/s) = irrigation area (ha) x flow rate (l/s/ha) Flow rate (l/s/ha) irrigation area (ha) flow capacity (l/s) 2 50 100 40. Required flow capacity (pumping) * Recommended flow rate is 2l/s/ha, or another higher flow rate. * Pumping rate = flow rate / number of pumping hours x24hours * flow capacity = irrigation area (ha) x flow rate (l/s.ha) Flow rate (l/s/ha) number of pumping hours (hour) pumping rate (l.s.ha) 41. Capacity of drain: How will the fields be drained? If ‘Irrigation canals provide drainage’ the canals must be sized (larger) top work as drains. So you have to carry on the question about the drain. If “No drain”, explain the following question, and then skip to question 48. Separate drain Canal as a drain No drain 42. Explain how excess rainfall and flood water will be drained from the fields? 43. Drain capacity * Recommended flow rate 3.5l/s/ha, or another higher flow rate. * Flow capacity (m3/s) = area (ha) x flow rate (m3/s/ha) Drainage area (ha) flow rate (l/s/ha) flow capacity (m3/s) 100 3.5 0.35 44. Will the drain collect water from catchments beyond the fields? * E.g. a stream flows into the head of the drain from a small catchment or another irrigation system? If “Yes”, answer the following questions, if “No” skip to question 48. Yes No 45. What is the catchment area in km2? If the catchment < 1.00km2 , Add this area to the area of fields above and recalculate new field drainage flow rate. If the catchment > 1.00km2, use “Applet form T22, flowStudy and Design Guidelines I-41
    • Part 2: Technical Forms external catchment” or get help from engineer to calculate the total flow (with the flow in the catchment above). 1.5 46. The flow rate of external catchment (m3/s) is: Use “Applet T22 external catchment” then copy form column C32. If the flow system of the external catchment is too complicate, you have to discuss with the engineer to get the flow capacity of this catchment. 2.61 47. Total drain design flow (m3/s) is the flow from irrigated area + flow from external catchment. * Value of question 43 + value of question 46. 2.96 48. Hydraulic design of canal and drain: remark Use “Applet T22 Hydraulic design of canal and drain” to calculate the minimum water height, bottom width and design velocity. 49. Responsibility for operation and maintenance: is there a Farmer Water Use Comity (FWUC) or similar group of people who are responsible for operation and maintenance of the earthwork. Yes No 50. Who will take to operate and maintain the earthwork ? 51. Remark Upload all of “Applet T22” that you used into “Project generator” for engineer to examine.Study and Design Guidelines I-42
    • Part 2: Technical Forms2.7.3 Form T23 Irrigation: StructureFormFirstly,determine the design flow across irrigation structure by: x For Small Irrigation Flow Control Structures calculating irrigated and/or drainage flow (If your irrigation project consists of both earthwork and structure, use the earthwork flow). x For Miscellaneous Irrigation Structures using Applet T23. In this applet you need to answer some questions about the hydrology of the catchment similar to Form T12 Road: Structure. Also the weir crest level and the maximum safe and acceptable upstream water level must be entered. The applet then outputs the length of the weir. These answers will need to be entered in the part of Spillways and diversion weirs belw.After that create output of Irrigation Structure then answer T23 questions on: x General project information – this fills automatically from information previously filled immediately when creating project. x Project location – enter GPS coordinates of the structure. x Proposed structure – select the structure type from the list, the remaining sections of the form appear as required by this choice. x Materials available for structure construction –a variety of questions about available structure construction material, its quality, and haul distance to the site. x Foundation soils including results for DCP tests – description options for type of soil and DCP test results with GPS coordinates (Enter each DCP test result to Applet T11 and get the 20 percentile DCP strength). x Road crossing – questions on whether a road crosses the structure, the type of road and the numbers and types of vehicle using the road. x Hydraulic capacity – questions require entry of the hydraulic capacity of the structure depending on whether it is a canal or drain (these answers come from the flow calculated above). There is also an important question whether the capacity can be exceeded (e.g. if a drain receives flow from an external catchment, or if a spillway passes a larger than design flood). The circumstance and consequences of an overdesign flood must be stated (this may require specialist advice). x Spillways and diversion weirs – questions will need to be answered if this type of output is proposed by copying from the applet T23 used above. x Pumping capacity – if the output is a pump then the pumping capacity must be confirmed, this may come from Form T22. x Responsibility for operation and maintenance – these question check whether there is a FWUC to take responsibility for design and maintenance and if not who will carry out design and maintenance.ExampleThe example shown is for a concrete spillway as part of the works to rehabilitate a KhmerRouge reservoir and irrigation system.For this example the attachments generated by the Project Generator will be: 1. No template drawing(s) are available for chosen output code(s), for the example shown a template is not suitable and a custom drawing will be needed on all occasions (See Part 3 of this Technical Manual).Study and Design Guidelines I-43
    • Part 2: Technical Forms 2. No quantities table to allow calculation of cost estimate (See Part 4 of this Technical Manual). 3. Specification (see Part 6 of this Technical Manual). 4. Construction check lists (see Part 7 of this Technical Manual).The flow chart and example Project Generator output follow below.Study and Design Guidelines I-44
    • Part 2: Technical Forms Flowchart for Technical Form T23 Irrigation: Structure Applet T23 calculates Design flow Possibly from form T22 design flow and (Small Irrigation Flow length of weir Control Structures) (Miscellaneous and use Study and Irrigation Structures) Design Guideline to Create determine the output Spillway weir.xls Output Spillway weir.xls General information? Location? Materials available? DCP Soils and measurements 20 percentile DCP Road crossing? Hydraulic capacity? Spillway/weir size? From Form(s) Pumping T22 capacity? x Drawings x QuantitiesStudy and Design Guidelines I-45
    • Part 2: Technical FormsExample Project Generator print Form T23 Irrigation: StructureForm T23 Irrigation structure(Concrete spillway) Province : Kampong cham District : Sreisanthor S/C:Roseisrok Name of project : New concret spillway construction Code of S/C : 31411 Name of TSO : Seila Date of form preparation : 20-07-2009 1. Location: where is the structure located within the Sangkat/Commune ? In Chongkoh village 2. Provide the coordinates of GPS. X of GPS Y of GPS 304010 1528230 3. Fill type 3 Source: borrow pit Source distance from structure (km) Borrow pit 0.3 4. Sands Source: borrow pit or stream bed. Source distance from structure (km) Borrow pit 0.1 5. Gravel Source: borrow pit or stream bed. Remark: for concrete work, the gravel from stream bed is not permitted. Source distance from structure (km) Borrow pit 1.5 6. Stone Source: quarry or stream bed. Type of stone: Hard metamorphic rock (granite, basalt, etc), limestone and sandstone. Source type of stone distance from structure (km) 7. Water supply for earthworkStudy and Design Guidelines I-46
    • Part 2: Technical Forms Source distance from structure (km) Bottom of reservoir 0.1 8. Foundation soils: what kind of soils is the structure founded on? If “Others”, fill the questions following. Very easily eroded soil Normal clay Sandy soil Gravel Earth with big stone in it Others 9. Other types of soils: mention them. 10. Foundation strength of DCP (mm/blow) and location of each test. * Location: stream bed road centre line, stream bed up stream, stream bed downstream, left bank abutment, right bank abutment or others. DCP (mm/blow) location 23 stream bed road centre line 15 left bank abutment 35 stream bed downstream 11. what is the 20 percentile DCP * You can calculate this value with Applet T11 30.2 12. Crossing structure: is there an existing crossing structure ? * if “Yes”, answer the following questions, if “Not”, go to “Flow capacity” Yes No 13. Road classification: District to districtStudy and Design Guidelines I-47
    • Part 2: Technical Forms District to commune Commune to commune Commune to village Village to village Farm acces 14. What is the largest vehicle that uses the earthwork? Passenger car People walking Motorcycle Motor-remorque Bicycle Animal cart Light vehicle/van Koyun Medium truck (6 tyres) Heavy truck (6 tyres) Bus (>4 tyres) Mini-bus (4 tyres). 15. Flow capacity: what is the design flow capacity (can be from T22), (m3/s)? * Calculated from canal capacity. You can skip this question for spillways or river intake. Generally, if the design structure is passed by the irrigation flow and drainage flow, you must design the structure the drainage flow, because its value is always higher. 16. What is the flow capacity at the structure (m3/s)?Study and Design Guidelines I-48
    • Part 2: Technical Forms * Calculated from canal capacity. You can copy skip question for spillways or river intake. Generally, if the design structure is passed by the irrigation flow and drainage flow, you must design the structure the drainage flow, because its value is always higher. 17. Can this flow capacity be higher than design one? If “Can”, answer the following questions, if “Can not” skip them. Can Can not 18. Describe the circumstance and consequence for the structure also what provision will be provided to survive an extreme flow? Using the design guidance spillways is sized for 1 in 50 year flow into the reservoir; the reservoir freeboard allows some of the flood to stay temporarily in the reservoir until it call all pass over the spillways. A concrete stilling basin and erosion protection will be provided downstream. 19. Did you use “Applet” to determine the design flow and length of structure? (Spillway and diversion weirs) * if you don’t design the spillway or river intake, skip them. Yes No 20. Spillway and diversion weirs: is the structure for reservoir or river intake? Reservoir River intake 21. What is the design flow for spillway or river intake (m3/s) ? * Copy from Applet T23, worksheet GTFM: C32. 15.35 22. What is the maximum safe water level at the upstream of structure? ( higher than this level, it can be flooded, overtopped). * Copy from Applet T23, worksheet GTFP: C33. 23Study and Design Guidelines I-49
    • Part 2: Technical Forms 23. What is the proposed weirs crest level? ( it is a full water level of a reservoir or river level intaking to the system). * Copy from Applet T23, worksheet GTFM:C34. 22.5 24. Required weirs length (m): * Copy from Applet T23, worksheet GTFM:C35. 26 25. Pumping capacity: provide the pumping capacity (m3/s). * Answer if there is a pumping, see the irrigation project form T22. 26. Responsibility for operation and maintenance: is there a Farmer Water User Comity (FWUC) or similar group of people who are willing to take responsibility to operate and maintain the structure? Yes No 27. Who will operate and maintain the irrigation structure? Commune council 28. Remark: Don’t forget to upload “Applet” that you used in your calculation.Study and Design Guidelines I-50
    • Part 2: Technical Forms2.8 Water Supply, Group Output Code 10300002.8.1 Form T31 Water SupplyTechnical Form T31 is used for all Water Supply Infrastructure projects including Wells, Ponds,Rainwater storage, and Piped water systems.Not different from the Transport and Irrigation Technical Forms one Form T31 can only be usedfor one output, e.g. if a project comprises a ring well, a mixed well, a water storage tank and apiped deliver system, there must be four forms T31.Because one Form T31 includes all of the questionnaires of Wells, Ponds, Rainwater storage,and Piped water systems, it is only necessary to answer to the questions related to the chosenoutputs, e.g. if a project contains only a ring well, answer only questions related to well, and skipquestions of ponds. Advice on questions needed to be answered and skipped are given in theProject Generator.Another feature of Form T31 is that the Project Generator will require it to be completed if thereis a water supply associated with another infrastructure output, e.g. a well for a school or healthpost.FormFirstly, create proposed output and then answer the below questions on: x General project information – this fills automatically from information previously filled immediately when creating project. x Project location – enter the GPS coordinates of the structure. x Number of proposed outputs – enter the number or sizes of the proposed output selected above. x Purpose of water supply – Select from four options: domestic, school, health facility or other. x Information about number of users – the questions identify the number and type of users; these are for statistical purposes not for calculation although the information can be used for a hand calculation if needed (see Part 5 of this Technical Manual). x Maintenance – manual entry of who will maintain the water supply facility. x Existing water supply – the questions are focused on where the people who will use the new water supply are getting water at present, this provides an indication of the benefit of the new water supply. x Information about site of proposed facility – the questions focus on ownership of the land used for the water supply and whether there is a flood risk which could interrupt or permanently contaminate the water supply. x Existing wells – for any water supply project that includes a new well or pond information from existing wells is the best indicator of water depth and variation over the year, water quantity and quality, the type of ground or rock where the well is sunk. Take time to collect and consider the information from as many wells as is practical. The questions are answered for each existing well. x Proposed well(s) – if new wells are required the questions concern the location, well depth, water depth and ground conditions at the well site, and potential causes of contamination. Some of the questions may be difficult to answer but make best use of information from existing wells or other local knowledge. The questions are answered for each well proposed.Study and Design Guidelines I-51
    • Part 2: Technical Forms x Suitable pump for well – the dynamic water level for the proposed well determines the type of pump which can be selected. x Proposed pond – the main issues for a pond are where the water will come from to fill it and whether it will have any water during the dry season. Ponds in sandy soil will may fill by groundwater flow but if groundwater level drops below the bottom of the pond during the dry season any water in the pond will soak away. Ponds in clay soils will not leak but rely on rainfall, water from a stream or deeper well during the dry season. x Each form is completed by confirming the required outputs which will generate the drawings and quantities for template designs which have been loaded into the Project Generator. Where no template exist, the description and quantities will have to be prepared separately.ExampleThe example is for a school water supply and comprises two outputs: x Drilled well with VN No6 pump. x Plastic rainwater tank filled by roof runoff.For this example the attachments generated by the Project Generator will be: 1. Template drawings for the drilled well with VN No6 pump. At the time of preparation of this manual there was no template for a plastic rainwater tank and roof collection system, the particular requirements will have to be prepared for the project e.g. by reference to MoEYS standards (See Part 3 of this Technical Manual). 2. Quantities table to allow calculation of cost estimate will be produced by the project generator. The water tank can be measured as ‘1 item’ (See Part 4 of this Technical Manual). 3. Specification (see Part 6 of this Technical Manual). 4. Construction check lists (see Part 7 of this Technical Manual).The flow chart and example Project Generator output follow below.Study and Design Guidelines I-52
    • Part 2: Technical Forms Flowchart for Technical Form T31 Water Supply Create output? General information? Location? List proposed outputs? What will be supplied? Number of users? Responsibility for maintenance? Existing water supply? Site information? Existing well information? Water Supply Continued belowStudy and Design Guidelines I-53
    • Part 2: Technical Forms Water Supply or Continued or from above or or Proposed Proposed Proposed Proposed pipe well(s)? Pond(s)? Tank(s)? system? Recommended Pump (advice) Confirm well Confirm pond Confirm tank Confirm pipe outputs? outputs? outputs? outputs? Well output Pond output Tank output Pipe output codes codes codes codes x Drawings x Drawings x Drawings x Drawings x Quantities x Quantities x Quantities x QuantitiesStudy and Design Guidelines I-54
    • Part 2: Technical FormsExample Project Generator print Form T31 Water SupplyForm T31 Water supply(VN6 pump) Province : Kampong cham District : Sreisanthor S/C:Roseisrok Name of project : Well for primary school Code of S/C : 31411 Name of TSO : Seila Date of form preparation : 20-07-2009 Location: where is the water supply located within the Sangkat/Commune? Phsar Leu primary school Provide the coordinates of GPS. X of GPS Y of GPS 304010 1528230 Number of proposed output: provide the number of proposed output? * Remark: Form T31 is only for one water supply output, it mean that, if you have many exactly the same output and same output data, you just make one output, answer just one technical form and provide the number of those output. 1 Purpose of water supply: for what purpose is the water supply used? If the “Village”, answer the question 5, if “School” or “Health center”, answer question 6. Village School Health centre Information about number of users: how many people use the water supply? In which village do they live? * Totalize the numbers above and write it down in the last row. Name of village people in village number of family using the water supply Number of supplier in school and health postStudy and Design Guidelines I-55
    • Part 2: Technical Forms * If you chose “School” in the answer above, write down only the number of rooms and number of students. If you choose “Health post” write down only the number of users in the health center. Number of school rooms number of students or health post 8 364 Maintenance: Who will maintain the water supply? Provincial department of education Existing water supply: how many families use the existing water supply? * if the existing water supply is for school, write down only “use for school”. Use for school Have the families who will use the supply agreed to form a Water Supply Committee? Yes No Where does the domestic water used by these people come from now? * Source: watercourse, natural pond, dug pond, rain water harvesting, spring, village well, household will, water-point piped. Totalize the number of users, and then write it down in the last row. Source number of users distance to the centre of village (km) Village well 250 0.3 Family well 200 0 Information about proposed facility: Who owns the land where the new facility will be constructed? * if the land is in private ownership, answer the question 12. Community Private Does the landowner agree to construction and unrestricted use of the facility? YesStudy and Design Guidelines I-56
    • Part 2: Technical Forms No Does the location of the facility ever flood? * if “Yes”, answer the questions 14 and 15. Yes No What is the depth of flooding in meters ? 0.15 What type of flooding? Seasonal and prolonged flooding from high river levels Short periods of flooding following heavy rain Existing well: what type of well are in the village or near vicinity? * You should choose the existing well which is closest to the new well Dug well Drilled well Mixed well 17. Provide the coordinates of GPS Type of well X of GPS Y of GPS Dug well 304090 1528230 18. What is the distance (closest) from the existing well to the proposed well (km)? 0.30 19. Who owns this existing well? villagers 20. Is the existing well used for domestic water or farming?Study and Design Guidelines I-57
    • Part 2: Technical Forms Domestic water Framing 21. How old is the existing well? 4 years 22. How deep is the existing well? 20 23. What is the static water level in the dry seasons? 4 24. What is the static water level in the wet seasons? 2 25. How many families use the sell? 40 26. Does the existing well have enough water all year? Enough Not enough 27. What does water from the well taste like? Note taste Salty Bitter 28. What is the color of the water in the existing well? Clear Gray YellowStudy and Design Guidelines I-58
    • Part 2: Technical Forms Brown 29. Does it smell? Yes No 30. Has the water from the existing well ever been tested for arsenic? Yes, ever No, never 31. What kind of soil or rock is the well sunk in? From depth (m) to depth (m) kind of soil or rock 0 6 silty sand 6 20 sandstone 32. How do you know about the information on the soil or rock? Commune chief told me. 33. How are the other well ? No information on other wells To many well to list Other wells similar 34. Proposed well: name of proposed well Phsar Leu primary school well 35. What kinds of soil or rock will the well sunk in? From depth (m) to depth (m), kind of soil or rock. From depth (m) to depth (m) kind of soil or rock 0 6 silty sand 6 20 sandstone 36. How deep is the water bearing soil or rock (the aquifer)?Study and Design Guidelines I-59
    • Part 2: Technical Forms 6 37. What is the depth of proposed well? 20 38. What is the static water level in the dry season (depth below ground in metres)? 4 39. What is the estimated dynamic water level in the dry season (drawn down by pumping) (depth below ground in metres)? 6 40. How do you know the information on the proposed well? Village well 41. Where will wastewater from the new well drain to? If “Other”, answer the question 43. Soak away Watercourse Pond Other 42. If “Other”, list your answers. 43. Is there anything close to the well that could cause contamination of the well? * If “Other”, answer the question 45. None Latrine Animal pens Cmetery Chemical store Fuel store Other 44. If other, list your answers.Study and Design Guidelines I-60
    • Part 2: Technical Forms 45. if a potential cause of contamination is identified, write it down. Consider another well location a safe distance from contamination source or explain in the box below what measures will be taken to prevent contamination. 46. Suitable pump for well VN N°6 pump, dynamic water level d 6m (suction pump) Afridev Tara, dynamic water level 0 to 25m (force mode) Seek specialist advice, dynamic water level > 50m None 47. Proposed pond: what kind of soil or rock will the pond be dug in? From depth (m) to depth (m) kind of soil or rock 48. Are there any wells, natural or dug ponds nearby? If “Yes”, answer the question 49. 49. If “Yes”, what is the standing water level in metres below ground level? Depth in dry season (m) depth in wet season (m) 50. Where will the water to fill the pond come from? If the answer is rainwater harvesting, answer question 52, if “Other”, answer question 53. Rainfall directly into pond Rainwater harvesting High groundwater levels Other 51. If “rainwater harvesting”, over what area will the water be harvested? 52. If “Other”, list your answer. Proposed Description Quantity Advice output Fill form T31 Water supply again and only Plastic water answer some relevant questions to your 1030511 tank filled by 1 chosen output and those questions are roof runoff recommended directly in the Project Generator.Study and Design Guidelines I-61
    • Part 2: Technical Forms2.9 Education Facility, Group Output Code 10400002.9.1 Form T41 Education FacilityTechnical Form T41 is used for all Education Facility Infrastructure projects including buildings,furniture, boundary walls and gates.Not different from the Transport and Irrigation Technical Forms one Form T31 can only be usedfor one output, e.g. if a project comprises a school building, furniture, and boundary walls, theremust be three forms T41.Because one Form T41 includes all of the questionnaires of school building, furniture, boundarywalls, and gates, it is only necessary to answer to the questions related to the chosen outputsand skip unrelated questions. Advice on questions needed to be answered and skipped aregiven in the Project Generator.However when a project such as a new school building includes a water supply facility such asa well, a Water Supply Form T31 is generated and must be filled. Similarly if a latrine building isneeded then a form Sanitation Form T101 is generated and must be filled.FormFirstly, create proposed output and then answer the below questions on: x General project information – form this fills automatically from information previously filled immediately when creating project. x Project location – enter the GPS coordinates of the education facility. x Quantity of proposed outputs – enter the number or length of the proposed outputs chosen above. x Information about education requirement – the question concern the numbers of children from different villages who use the school, travel distance, number of existing and proposed classrooms, availability of teachers and the school management committee. x Physical characteristics of the site – questions relate to flooding, UXO, land title, whether the site is large enough, whether there is a water supply and whether sanitation facilities exist. x Foundation soils – the form provides for filling trial pit logs and recording DCP results, as many as necessary.ExampleThe example is for: x a new five room school, x primary school furniture (25 four student desks, 50 two student desk, five teacher tables and chairs) x 80 m of boundary wall, x four latrines, and x one wellFor this example the attachments generated by the Project Generator will be: 1. Template drawing(s) when available for chosen output code (See Part 3 of this Technical Manual). 2. Forms T31 and T101 generated for outputs in Water Supply and Sanitation respectivelyStudy and Design Guidelines I-62
    • Part 2: Technical Forms 3. Quantities table to allow calculation of cost estimate will be produced by the project generator (See Part 4 of this Technical Manual). 4. Specification (see Part 6 of this Technical Manual). 5. Construction check lists (see Part 7 of this Technical Manual).The flow chart and example Project Generator output follow below.Study and Design Guidelines I-63
    • Part 2: Technical Forms Flowchart for Technical Form T41 Create Education Facility output? General information? Location? Quantity of proposed outputs? Educational requirement? Sanitation: Latrine Information Water supply: water codes about site? supply codes DCP Soils and measurements 20 percentile DCP x Drawings x QuantitiesStudy and Design Guidelines I-64
    • Part 2: Technical FormsExample Project Generator print Form T41 Education FacilityForm T41 EducationBrick School of 5 room Province : Kampong cham District : Sreisanthor S/C:Roseisrok Name of project : Roseisrok Primary School Code of S/C : 31411 Name of TSO : Seila Date of form preparation : 20-07-2009 1. Location: where is the education facility located within the Sangkat/Commune? Describe the location of education facility. 1Km from Sreisanthor commune centre 2. Provide the coordinates of GPS * Coordinate of school location X of GPS Y of GPS 304010 1528230 3. List the number and length of the proposed facility. * Rooms of the new school, list the number of room. Furniture: list the number of set of chairs and tables. Primary school, training room, library, school dormitory, school yard, list the number of place. List the length of school wall and school fence in meters. Bricks school 5 rooms with roof tile, concrete floor. 4. Information about education requirement: (about students) How many students will use the school and which village will they come from? Name of village Number of children go to distance from village to the school school in kilometers Phsar Leu 52 4 Phsar Chhnang 108 3 Chongkoh 84 1 Som Roang 120 0 5. Total number of children goes to the school. 364 6. About the number of classroom. How many classrooms on the site now?Study and Design Guidelines I-65
    • Part 2: Technical Forms 3 7. About the number of teachers teachers provided by the teachers will be hired for Total number of teachers education department the school available 2 3 8 8. About the school management: is there a school parent’ committee? Yes No 9. Physical characteristics of the site: does the site ever flood in the wet season? * if “Ever”, answer the two following questions. Ever Never 10. What is the maximum depth of flooding in meters? 0.15 11. What type of flooding? Seasonal flooding and prolonged by the high river level Short periods of flooding following heavy rain 12. Is the site free of mines and UXO? * if “Yes”, answer the following question. Yes No 13. Does land title exist for the site? * If “Yes”, answer the following questions. YesStudy and Design Guidelines I-66
    • Part 2: Technical Forms No 14. What stage is the documentation (district, province…)? Province 15. Is the site presently occupied? * If “Yes”, answer the following questions Yes No 16. Whom or what? (E.g. building, rice field and will compensation be expected/demanded?) Old school 17. Is the site presently walled or fenced? Yes No 18. Will land fill or embankments be needed to protect against flooding? * If “Yes”, answer the question 19 Yes No 19. If “Yes”, describe it. 20. Is there enough space for students to play sports? Yes No 21. Is there enough space to build more classrooms in the future? Yes NoStudy and Design Guidelines I-67
    • Part 2: Technical Forms 22. What is the water supply at the site? * If “Pond” or “Pumping well”, answer the following question None Pond Pumping well Piped supply from off site 23. Write down the dry season water level below ground (m) 2.6 24. How many existing latrines at the sites? 0 25. Foundation soils: (for school building construction, school fence and walls) What kind of soil will the school be constructed on? * Type of soil: gravel, silty sand, micaceous sand, lateritic sand, clayey sand, loams, organic clays, lateritic clays, dandy, silty or clayey peats. Number X of Y of Depth (m) Type of soil group of soil of trial pit GPS GPS 1 304015 1528220 0.15 organic Fine grained, silt cohesive 1.5 silty sands course grained, non- cohesive 2.0 gravel course grained, non- cohesive 26. DCP test (mm/blow) DCP (mm/blow) X of GPS Y of GPS 23 304015 1528220 15 304000 1528222 23 304030 1528218 27. 20 percentile of DCP (mm/blow) 30.2Study and Design Guidelines I-68
    • Part 2: Technical Forms Proposed Description Quantity Advice output Fill form T41 Education Facility four student desks=25 again and only answer some primary two student desk= 50 relevant questions to your chosen 1040501 school teacher tables and output and those questions are furniture chairs =5 recommended directly in the Project Generator. Fill form T41 Education Facility again and only answer some relevant questions to your chosen 1040405 boundary wall 80m output and those questions are recommended directly in the Project Generator. Fill form T101 Sanitaiono and only answer some relevant questions to 1100102 four latrines 1 your chosen output and those questions are recommended directly in the Project Generator. Fill form T31 Water supply and only answer some relevant questions to 1030201 well 1 your chosen output and those questions are recommended directly in the Project Generator.Study and Design Guidelines I-69
    • Part 2: Technical Forms2.10 Health, Group Output Code 10500002.10.1 Form T51 HealthTechnical Form T51 provides for all Health infrastructure projects.Not different from the Transport and Irrigation Technical Forms one Form T51 can only be usedfor one outputs, e.g. if a project comprises buildings, incinerator, and boundary fence, theremust be three form T51.Because one Form T51 includes all of the questionnaires of health building, Incinerator walls,fence and gates, it is only necessary to answer to the questions related to the chosen outputs.Advice on questions needed to be answered and skipped are given in the Project Generator.However when a project such as a new health post includes a water supply facility such as awell, a Water Supply Form T31 is generated and must be filled. Similarly if a latrine building isneeded then a form Sanitation Form T101 is generated and must be filled.FormFirstly, create proposed output and then answer the below questions on: x General project information – this fills automatically from information previously filled immediately when creating project. x Project location – by entering the GPS coordinates of the education facility. x Quantity of proposed outputs – enter the number or length of the proposed outputs chosen above. x Information about health facility – the village, populations and distances travelled tpo reach the health facility as well as the availability of trained staff. x Physical characteristics of the site – questions relate to flooding, UXO, land title, whether the site is large enough, whether there is a water supply and whether sanitation facilities exist. x Foundation soils – the form provides for filling trial pit logs and recording DCP results, as many as necessary.ExampleThe example is for: x a concrete health post, x 120 m of boundary fence, x one wooden gate, x one latrines building x one rainwater collection and storage tank, and x one well:For this example the attachments generated by the Project Generator will be: 1. Template drawing(s) when available for chosen output code(s) (See Part 3 of this Technical Manual). 2. Forms T31 and T101 generated for outputs in Water Supply and Sanitation respectively 3. Quantities table to allow calculation of cost estimate will be produced by the project generator (See Part 4 of this Technical Manual). 4. Specification (see Part 6 of this Technical Manual).Study and Design Guidelines I-70
    • Part 2: Technical Forms 5. Construction check lists (see Part 7 of this Technical Manual).The flow chart and example Project Generator output follow below.Study and Design Guidelines I-71
    • Part 2: Technical Forms Flowchart for Technical Form T51 Create Health output? General information? Location? Quantity of proposed outputs? Health service requirement? Sanitation: Latrine Information Water supply: water codes about site? supply codes DCP Soils and measurements 20 percentile DCP x Drawings x QuantitiesStudy and Design Guidelines I-72
    • Part 2: Technical FormsExample Project Generator print Form T51 HealthForm T51 HealthConcrete health centre Province : Kampong cham District : Sreisanthor S/C:Roseisrok Name of project : Roseisrok Health Post Code of S/C : 31411 Name of TSO : Seila Date of form preparation : 20-07-2009 1. Location: where is the health facility located within the Sangkat/Commune? Next to the commune centre, in Phsar Leu market 2. Provide the coordinates of GPS * First line is the starting point; last line is the ending point X of GPS Y of GPS 304010 1528230 3. List the number and length of output chosen. * Fence in meter, and other output in number. 1 4. Information about health facility: how many people will use the health facility and which villages will they come from? * Copy the total number of people from the Project Information Form. 388 5. How many trained staff will be provided by the health department? 5 6. How many staff will be hired for the health facility? 4 7. What is the total number of staff available? * totalize both numbers above. 9 8. Physical characteristics of the site: does the site ever flood in the wet season? * if “Ever”, answer the following questions.Study and Design Guidelines I-73
    • Part 2: Technical Forms Ever Never 9. If “Ever”, what is the maximum depth of flooding in meters? 10. If “Ever”, what type of flooding? Seasonal and prolonged flooding from high river levels. Short periods of flooding following heavy rain. 11. Is the site free of mines and UXO? Yes No 12. Does land title exist for the site? If yes, at what stage is the documentation (district, province…) Province 13. Is the site presently occupied? If yes, list them. * e.g. building, rice field… will compensation be expected/demanded? Old health post 14. Is the site presently walled or fenced? Yes No 15. Will land fill or embankments be needed to protect against flooding? Yes No 16. What is the water supply at the site? NoneStudy and Design Guidelines I-74
    • Part 2: Technical Forms Pond Pumping well Piped supply from off site 17. How many existing latrines at the site? 0 18. Foundation soils: what kind of soil will the health facility be constructed on? * Kind of soil: gravel, silty sand, micaceous sand, lateritic sand, clayey sand, loams, clayey silts, organic silts, micaceous silts, sandy clays, silty clays, organic clays, sandy; silty or clayey peats. Number X of Y of Depth (m) Type of soil group of soil of trial pit GPS GPS 1 304015 1528220 0.15 organic Fine grained, silt cohesive 1.5 silty sands course grained, non- cohesive 2.0 gravel course grained, non- cohesive 19. Foundation strength DCP Test (mm/blow). DCP (mm/blow) X of GPS Y of GPS 23 304015 1528220 15 304000 1528222 23 304030 1528218 20. 20 percentile of DCP (mm/blow) ? 30.2 Proposed Description Quantity Advice output Fill form T51 Health again and only answer some relevant questions to boundary your chosen output and those 1050112 120m fence questions are recommended directly in the Project Generator. Fill form T51 Health again and only answer some relevant questions to your chosen output and those 1050114 wooden gate 1 questions are recommended directly in the Project Generator.Study and Design Guidelines I-75
    • Part 2: Technical Forms Fill form T101 Sanitation and only answer some relevant questions to 1100102 four latrines 1 your chosen output and those questions are recommended directly in the Project Generator. Fill form T31 Water supply and only rainwater answer some relevant questions to 1030511 collection and 1 your chosen output and those storage tank questions are recommended directly in the Project Generator. Fill form T31 Water supply again and only answer some relevant questions to your chosen output 1030201 well 1 and those questions are recommended directly in the Project Generator.Study and Design Guidelines I-76
    • Part 2: Technical Forms2.11 Sanitation, Group Output Code 11000002.11.1 Form T101 SanitationTechnical Form T101 provides for all Sanitation infrastructure projects.Not different from the Transport and Irrigation Technical Forms one Form T101 can only beused for one output, e.g. if a project comprises several sections of covered drain and pipe crossconnections, there must be two form T101.Because one Form T101 includes all of the questionnaires of laterine, waste water, Solid wastemanagement, and drainage, it is only necessary to answer to the questions related to thechosen. Advice on questions needed to be answered and skipped are given in the ProjectGenerator.Form x General project information – this fills automatically from information previously filled immediately when creating project. x Project location – enter the GPS coordinates of the proposed output, if it is a linear project such as a covered drain enter the start and finish coordinates, if it is a point project such as school laterine, enter a coordinate of the laterine. x Quantity of proposed outputs – enter the number or length of the proposed outputs chosen above. x Capacity of drain – questions need to be answered if one of the project outputs is a drain. Questions include the plan area of the ground drained, guidance is given on estimating this. The default runoff rate is 3.5 l/s/ha but this can be overwritten (but do not enter a lower rate). The form asks if water from upstream can flow into the drain and the catchment area; if the area is ” 1 km2 (100 ha) then the form includes discharge for the area, if the area is larger then it cannot pass down the drain because the flow would be too large and another outfall must be found. x hydraulic design of channel drain – if the output is a channel drain Applet T101 calculates the size of the drain. There is an option to accept or override the preceding capacity calculation (but do not enter a lower capacity). Enter the bed levels and length of the drain, bed width, side slope and Manning’s ‘n’ using the guidance on the form. The calculation is iterative. A water depth is entered: if it is too small the Applet instructs to ‘Increase depth’; if it is too large the form instructs to ‘Decrease depth’; if the depth is correct (within a band of tolerance) the form prints ‘Depth OK’. The Applet then outputs the: minimum height of banks above bed level; width between tops of bank; and velocity of design flow. After that you need to copy all of these results to the generator. x Hydraulic design of pipe drain (once for each drain) – enter the depth of the bottom of the pipe below ground and the length of drain. You then calculate the maximum hydraulic gradient. Use the tables on the form to select the minimum pipe diameter, it is permitted to go a size or more up to a larger diameter. There are different tables for plastics and concrete pipes.ExampleThe example is for covered channel drains both sides of road through a village center, eachabout 100 m in length, including a connecting pipe beneath the road to outfall.For this example the attachments generated by the Project Generator will be: 1. Template drawing(s) when available for chosen output code(s) (See Part 3 of this Technical Manual).Study and Design Guidelines I-77
    • Part 2: Technical Forms 2. Quantities table to allow calculation of cost estimate will be produced by the project generator (See Part 4 of this Technical Manual). 3. Specification (see Part 6 of this Technical Manual). 4. Construction check lists (see Part 7 of this Technical Manual).The flow chart and example Project Generator output follow below.Study and Design Guidelines I-78
    • Part 2: Technical Forms Flowchart for Technical Form T101 Create Sanitation output? General information? Location? Quantity of proposed outputs? Calculation in the Capacity of form drain(s)? Applet calculates size of channel Applet calculates advise size of pipe Size of T101 Channel drain(s)? design.xls Pipe chart.xls x Drawings x QuantitiesStudy and Design Guidelines I-79
    • Part 2: Technical FormsExample Project Generator print Form T101 SanitationForm T101 Sanitation and drainage(Box drain) Province : Kampong cham District : Sreisanthor S/C:Roseisrok Name of project : Phsar Leu Drainage System Code of S/C : 31411 Name of TSO : Seila Date of form preparation : 20-07-2009 1. Location: where is the sanitation and drainage located within the Sangkat/commune? Describe the location The box drain locates in the centre of Phsar Leu village. 2. Provide de coordinate of GPS. * if it is a point, fill only the first row. First row is the starting point and the second row is the ending point. X of GPS Y of GPS 304010 1528230 305100 1528250 3. Description of requirements: give a brief description about the project. Build covered channel drains both sides of road through Phsar Leu, each about 100 m in length, include pipe from north to south side of road to outfall. 4. List the number or length of the proposed outputs. * provide the number for the latrines and length for the drain. Output Number or length Box drain 200 5. Drainage capacity: give drain a name; area of land drained, flow rate (m3/s/ha), flow capacity and external catchment. * in peri-urban or village can allow for 50m wide strip from road centerline for drains each side of road. Recommended flow rate is 3.5l/s/ha, but you choose another value. The required flow capacity of drain = flow rate x drained area. Will the drain collect water from catchments beyond the drain, e.g. a stream flow into the head of the drain from a small catchment or drain system? Write down “Collect” or “Does not collect”.Study and Design Guidelines I-80
    • Part 2: Technical Forms Name of drain Drained area Flow rate Flow capacity External (ha) (l/s.ha) (l/s) catchment Box drain, 0.5 0.5 2.5 Collect north of Phsar Leu Box drain, 0.5 0.5 2.5 Does not south of collect Phsar Leu6. Remark * if you chose “Collect”, answer the two following questions.7. Describe briefly how the extra catchment affects the requirements, e.g. it may only affect a drain one side of the road. Name of drain Description Box drain north of Phsar Leu There is irrigation area of 30ha flows in the north Phsar Leu box drain8. Give a name of drain collecting water from external catchment, area of external catchment, flow rate (l/s/ha) and extra flow capacity. * if catchment area > 1.0Km2, flow from this catchment will be too big for a culvert or a drain, so let think about the flow conveyance or a special advice. * Recommended drain flow capacity is 3.5l/s.ha, but you can choose another one. * flow capacity extra = catchment area (ha) x flow rate (l/s.ha). Name of drain External catchment Flow rate (l/s.ha) Extra flow capacity area (ha) (l/s) Box drain north of 30 3.5 105 Phsar Leu9. Calculate the total design flow capacity for box culvert (l/s). * Total design flow capacity = drain flow capacity (l/s) + extra flow capacity of external catchment (l/s) Name of drain Design flow capacity (l/s) Box drain north of Phsar Leu 107.5 Box drain south of Phsar Leu 2.510. Design of box drain: remark You must use “Applet Form T101 Drain” to determine the design flow, channel bed level, bottom width and channel velocity.11. Result of the design of box drain and drain from Applet T101. * Skip it if you don’t design the box drain. Copy the answer from Applet T101 that you used to calculate. Study and Design Guidelines I-81
    • Part 2: Technical Forms Name of drain Required flow Bed depth (m) Width of box Design velocity capacity (l/s) drain (m) (m/s) Box drain 107.5 0.49 0.6 0.46 north of Phsar Leu Box drain 2.5 0.19 0.15 0.18 south of Phsar Leu 12. Design of pipe drain: remark Use “Applet Pipe Chart” to determine the diameter of pipe drain. 13. Result of the design of pipe drain from Applet Pipe Chart * Skip it if you don’t design the pipe drain. * calculate the flow capacity, see the suitable pipe and copy the answer from Applet Pipe Chart that you used. Name Required Pipe Pipe Efficient Type of Minimum Chosen of drain flow drain length hydraulic pipe diameter diameter capacity depth (m) gradient (m) (m) (l/s) (m) 14. Remark Upload the Applets you’ve used to get the result as above.Study and Design Guidelines I-82
    • Part 2: Technical FormsForm T101 Sanitation and drainage(Pipe drain)Province : Kampong cham District : Sreisanthor S/C:RoseisrokName of project : Phsar Leu Drainage System Code of S/C : 31411Name of TSO : Seila Date of form preparation : 20-07-2009 1. Location: where is the sanitation and drainage located within the Sangkat/commune? Describe the location. At the Phsar Leu village centre 2. Provide de coordinate of GPS. * if it is a point, fill only the first row. First row is the starting point and the second row is the ending point. X of GPS Y of GPS 304500 1528240 304530 1528260 3. Description of requirements: give a brief description about the project. Pipe drain, connecting from the north box drain, north to south, to the south of drain outlet. 4. List the number or length of the proposed outputs * provide the number for the latrines and length for the drain. Output Number or length Pipe drain 100 5. Drainage capacity: give drain a name; area of land drained, flow rate (m3/s/ha), flow capacity and external catchment. * in peri-urban or village can allow for 50m wide strip from road centerline for drains each side of road. Recommended flow rate is 3.5l/s.ha, but you choose another value. The required flow capacity of drain = flow rate x drained area. Will the drain collect water from catchments beyond the drain, e.g. a stream flow into the head of the drain from a small catchment or drain system? Write down “Collect” or “Does not collect”. Name of drain Drained area Flow rate Flow capacity External (ha) (l/s.ha) (l/s) catchment Pipe drain, 0.5 5 2.5 Collect downstream of Phsar Leu 6. Remark Study and Design Guidelines I-83
    • Part 2: Technical Forms * if you chose “Collect”, answer the two following questions. 7. Describe briefly how the extra catchment affects the requirements, e.g. it may only affect a drain one side of the road. Name of drain Description Pipe drain downstream of Phsar With 30ha of irrigation area, flow to Leu the north of road 8. Give a name of drain collecting water from external catchment, area of external catchment, flow rate (l/s.ha) and extra flow capacity. * if catchment area > 1.0Km2, flow from this catchment will be too big for a culvert or a drain, so let think about the flow conveyance or a special advice. * Recommended drain flow capacity is 3.5l/s.ha, but you can choose another one. * flow capacity extra = catchment area (ha) x flow rate (l/s.ha). Name of drain External catchment Flow rate (l/s.ha) Extra flow capacity area (ha) (l/s) Pipe drain 30 3.5 105 downstream of Phsar Leu 9. Calculate the total design flow capacity for box culvert (l/s). * Total design flow capacity = drain flow capacity (l/s) + extra flow capacity of external catchment (l/s) Name of drain Design flow capacity (l/s) Pipe drain downstream of Phsar Leu 107.5 10. Design of box drain: remark You must use “Applet Form T101 Drain” to determine the design flow, channel bed level, channel bottom width and channel design velocity. 11. Result of the design of box drain and drain from Applet T101. * Skip it if you don’t design the box drain. Copy the answer from Applet T101 that you used to calculate. Name of drain Required flow Bed depth (m) Width of box Design velocity capacity (l/s) drain (m) (m/s) 12. Design of pipe drain: remark Use “Applet Pipe Chart” to determine the diameter of pipe drain.Study and Design Guidelines I-84
    • Part 2: Technical Forms13. Result of the design of pipe drain from Applet Pipe Chart * Skip it if you don’t design the pipe drain. * calculate the flow capacity, see the suitable pipe and copy the answer from Applet Pipe Chart that you used. Name of Required Pipe Pipe Efficient Type of Minimum Chosen drain flow drain length hydraulic pipe diameter diameter capacity depth (m) gradient (m) (m) (l/s) (m) Pipe drain 107.5 1 100 0.008 Concrete 0.8 0.8 downstream of Phsar Leu14. Remark Upload the Applet you used to get the result as above. Study and Design Guidelines I-85
    • PART 3:TEMPLATE DESIGNS FORLOCAL INFRASTRUCTURE I-86
    • Part 3: Template Designs for Local Infrastructure3 Template Designs for Local Infrastructure3.1 BackgroundThe C/S Fund is able to support a wide range of small infrastructure projects. The PIM atAnnex 2 lists common and know types of infrastructure project allocating each a seven-digitnumerical output codes. This is a ‘live list’ which might be amended and added too as specialand generic project requests evolve over time.In order to speed the process a selection of standard ‘Template’ designs was developed underthe Seila Program, these included types of infrastructure most commonly requested by thecommunes or sangkats, and also a few simple but rarely built designs. This system provedpopular and successful with the communes and sangkats as evidenced by the large number of‘Seila’ projects built around Cambodia, albeit that some types of infrastructure are prone totechnical deficiencies.The ‘Template’ designs comprised simple drawings. Parts and some of the drawings wereprepared using AutoCAD but the finished drawings were assembled as MS Excel spreadsheets.This allowed selection of alternative dimensions and automatic calculation of quantities. Thiswas applied using the ‘Seila Template Program’; which is a customized software package.Although it was very useful and worked well within its limits, the Seila Template Program wasfound to be rather inflexible. In particular it was difficult to change or add new template designs.It was therefore decided that for NCDD the C/S Fund process needed a new program whichallowed easy changes and additions of templates. The new program is called the ‘ProjectGenerator’. At the same time it was decided to review and update all the existing templatedesigns.3.2 NCDD TemplatesThe new NCDD templates are AutoCAD drawings. However, they are saved for the projectgenerator as Adobe PDF files. The Project Generator outputs the chosen template drawings tothe project folder as PDF files. This means there is no need for Technical Assistant to have oruse AutoCAD.The NCDD template drawings no longer incorporate quantity spreadsheets (Note January 2009PIM needs correcting on this point). These are now been separate MS Excel files for eachtemplate. They are called in and output separately by the Project Generator. This is discussedat Section 5.3.3 Available TemplatesAs previously, templates have been produced for common infrastructure outputs. There are nottemplates for every output code. The intention is that whenever an output is required for whichthere is no template, then this can be prepared as a new template and added to the ProjectGenerator at that time.Available templates are not listed here because the list is expected to change and increaseregularly.3.4 How to Read and Use the Drawings3.4.1 SizeThe Template drawings for infrastructure outputs are prepared at original paper size A3. Theyshould be printed at A3 size when they are used as drawings for the construction contract sothat they are easy to read. Either photocopy the drawings to A3 size, or print them at A3 sizefrom the computer.The drawings can also be printed at A4 size, the letter sizes and other details have beenchosen to be readable at this size, although they are obviously smaller than at A3 size. It isadvised to use ‘standard’ or ‘high’ quality printer setting at A4 size, not ‘low’ or ‘economy’Study and Design Guidelines I-87
    • Part 3: Template Designs for Local Infrastructuresettings. This will ensure the A4 prints can be read, particularly if copied successively on aphotocopier because each round of photocopying looses quality.3.4.2 Drawing scalesThe stated scales on the drawings are at A3 size. Scale bars are included for when drawingsare printed at A4 size.3.4.3 DimensionsAll of the dimensions needed to construct the output are shown on the drawings. If a dimensionis missing, resolve the matter locally or by seeking advice from supervisors. In every caseadvise the supervisor who should ensure that the drawing is amended to show the missingdimension (see 3.4.4).Most dimensions are in millimeters. Some dimensions are in meters, but this is always shownon the drawing. So, ‘2000’ means 2000 millimeters, or 2 meters; ‘2 m’ means 2 meters.3.4.4 RevisionsEach drawing sheet includes a revision table above the title block. This is to be filled whenevera template drawing is changed so that there is a history of the change. The amended designmust be reloaded to the Project Generator; amending also the quantity tables if necessary (seePart 5).The box should also be filled if a template is changed to fit the requirements of a particularproject. This can be done in hand on hard copy issued to the contractor. Senior advisorsshould be consulted to confirm such change and can decide if this change should apply only forthe project or for wider use of the Template.3.4.5 Variable dimensionsSome template drawings have dimensions that can be varied (e.g. high fill over a pipe culvertrequires a longer culvert and more culvert rings). It is not necessary to alter the templatedrawing, the variation in dimension is taken into account in the quantity spreadsheet, see Part 5.3.4.6 How to read the steel details and the steel scheduleFor most outputs with reinforced concrete elements, separate reinforcement drawings areincluded, with separate bar schedules. For some small outputs (e.g. width restriction posts) thereinforcement requirement and schedule is included on the drawing.On a design drawing, reinforcement is usually divided into ‘position’ sets of bars. Each set islabeled by a number (e.g. f), the number of bars used, the diameter of bar and the spacing.Following construction industry convention and the software settings (see below) bars thedescription of bars may be in several ways. Bar call-up type and arrangement Description f10Ø10@200 Position 4, 10 bars diameter 10 mm, spacing 200 mm 10Ø10@200f 10 bars diameter 10 mm, spacing 200 mm, position 4 fØ10@200 Position 4, diameter 10 mm, spacing 200 mm 10Øf Diameter 10 mm, position 4When bar schedules have been produced these have been generated using SofiCAD, which isa proprietary add-in software for AutoCAD (see section 3.5). It is not essential to use SofiCADfor producing future template designs. However the use of software makes drawing productioneasier and reduces mistakes so it is advisable to use software for more complicated drawings.Using SofiCAD will ensure consistency with existing Templates.Study and Design Guidelines I-88
    • Part 3: Template Designs for Local InfrastructureWhenever there is an output that has a bar schedule this is loaded and output by the ProjectGenerator together with the drawing.An example of a bar schedule is shown below. The schedule shows the output number andsteel grade for the bars.The columns are as follows: x Pos: position, (e.g. same as f on the drawing example above). x No: number of bars at that position. x d: diameter in millimeters. x Length: total length of each piece of bar before bending in meters. x Dbr ds: Not used. x Type: Bar type, A1 is deformed/high yield, D1 is round bar. x Shape code: A diagram showing the shape and dimensions of a bent bar, where dimensions vary because of a tapering shape, a table is included to show the dimensions of each bent bar. Dimension of figures are centimeters. x Total length: Total length of steel used for all the bars at that position (e.g. for position f total length 26 x 1.9 = 49.4 meters). x Weight: Total weight of the total length of bar in kilograms.3.5 AutoCAD StandardsThe templates have as far as practical been produced to a standard AutoCAD format. This isnot 100% applicable, e.g. some templates have elements carried over from the SeilaStudy and Design Guidelines I-89
    • Part 3: Template Designs for Local InfrastructureTemplates. It is desirable that any additional templates also follow the same standardAutoCAD format. The remainder of this sub-section specifies the AutoCAD format.All drawing prepared using the AutoCAD software should comply with these instructions in orderto facilitate data exchange and uniformity of layout.3.5.1 AutoCAD VersionAutoCAD versions released between year 2004 and 2008 have been used for all templatesproduced up to first issue of this Technical Manual. Regardless of the version of AutoCAD withwhich the drawings are produced, all drawings files are to be saved in AutoCAD 2004 format.3.5.2 General settings x All design work should be done in MODEL space. x The drawing unit for the MODEL space shall be ‘meters’. Drawing dimensions are in ‘millimeters’. x Setting drawing units Menu > Format > Units > Length: Type: Decimal Precision: 0.0000 > Angle: Type: Decimal degrees Precision: 0.000 > insertion scale: Unit to scale inserted content: meterx Setting line type All linetypes should be loaded form acadiso.lin (metric system)x Setting line scale The default setting for the Global Scale Factor is 1.0. It needs to be adjusted for different drawing scales. Always adjust the Global Scale Factor so that axes and hidden lines are readable. Adjustments to the Linetype Scale of single lines are needed for the secondary scales such as details. Adjustment is to be based on the leading scale: eg. If your drawing scales are: 1:50, 1:10, your global scale is to be 0.05 and the linetype scale of the single lines for the scale 1:10 should be scale to: 0.2 = (10/50). (Means x = the smaller scale divided by the bigger scale). Menu > FORMAT > LINETYPE > adjust Global Scale Factor > disable “Use paper space units for scaling”x The drawing frame, title block and scale bars and legends have to be in LAYOUT space. All other objects shall be in MODEL space.x Regardless of the version of AutoCAD with which the drawings are produced, all drawings files are to be saved in AutoCAD 2004 format. Set software as follows: Menu > TOOLS > OPTIONS > tab Open and Save > Save as: AutoCAD 2004 (*.dwg)3.5.3 AutoCAD file nameThe drawing file name is the NCDD output and sheet number(s) of the drawing(s) it contains.3.5.4 Drawing numberDrawings are identified by the NCDD output number and sheet number.Study and Design Guidelines I-90
    • Part 3: Template Designs for Local Infrastructure3.5.5 Paper sizeA3 ISO paper formats shall be used. Name of Paper Size Drawing Margins Format [mm] Area [mm] Left Right Above Below ISO A3 420 x 2973.5.6 Pen assignment for plottingPlot style table file NCDD.ctb is to be used for all plots.The files contain the following pen assignments. Line Width No. of Color Color Pen Color NCDD.ctb 1 Red (1) Black (7) 0.18 2 Yellow (2) Black (7) 0.25 3 Green (3) Black (7) 0.35 4 Cyan (4) Black (7) 0.5 5 Blue (5) Black (7) 0.7 6 Magenta (6) Black (7) 1.0 7 White/Black (7) Black (7) 0.10 8 Dark Grey (8) Black (7) 0.05 9 Bright Grey (9) Dark grey (250) 0.053.5.7 Layer definitionThe layers and settings listed below should be used as much as possible.General layer Plot Layer Name Description Color Line Type Yes/No1-AXIS Axes, Centre lines White Centre21-DIM Dimensions and Elevations Red Cont.1-HATCH General layer for hatches 8 Cont.1-HELP-OFF Help lines Magenta Cont. no1-INV Invisible edges in general Red /White Hidden1-CUT-LINE Section or cut lines Green Centre1-TEXT General text, and Table Red Cont.Z-FRAME Frame Yellow Cont.Z-VIEWPORT View port visible 9 Cont.Z-VIEWPORT-OFF View port invisible Magenta Cont. noTITLEBLOCK The block of title Yellow Cont.Study and Design Guidelines I-91
    • Part 3: Template Designs for Local InfrastructureLayers for architectural and civil drawings Plot Layer Name Description Color Line Type Yes/No Green CON-SEC Concrete sections Cont. /Red CON-VIEW Concrete view Yellow Cont. Furniture and decoration FURNITURE White Cont. (cars, people, etc.) ACAD_IS GEOTEX Geo-textile Cyan O10W100 Geo-technical information, GEOTECH Red Cont. boreholes, DCP, etc. MASONRY-VIEW Masonry, Brick wall Yellow Cont. MASONRY-SEC Masonry, Brick wall Green Cont. Red OPENING Doors and windows Cont. /White OTHER Miscellaneous Objects variable variable REBARS Rebar lines and sections Yellow Cont. ROAD-VIEW Road limit line Yellow Cont. ROAD-SEC Road section Green Cont. STEEL-VIEW Steel structure Yellow Cont. STEEL-SEC Steel structure Green Cont. TIMBER-VIEW Wood structure Yellow Cont. TIMBER-SEC Wood structure Green Cont. Ground section line and TREE Green Cont. vegetationNOTE: If additional layers are required, please inform the project manager.If you come across layers with similar names but different spelling eliminate theincorrect layer from the drawing.3.5.8 Text style and fontsText should be created with the MULTILINE EDITOR which facilitates text wrapping.Do not explode multi-line text. Set the text style to Arial Narrow.Menu>Format>Units > Style name: Arial Narrow > Font name: Arial Narrow Height Height In Model Space Description Text Style Color In Layout 1:1000 1:500 1:100 1:50Headings Arial Narrow Green 4mm 4 2 0.4 0.2Sub headings Arial Narrow Yellow 3mm 3 1.5 0.3 0.15Common text/labels Arial Narrow Red 2mm 2 1 0.2 0.1Notes, dimensions,elevations, Arial Narrow Red 2mm 2 1 0.2 0.1inscriptions, legendAxis labels Arial Narrow Yellow 4mm 4 2 0.4 0.2Study and Design Guidelines I-92
    • Part 3: Template Designs for Local Infrastructure3.5.9 Line types / widthsStandard metric system AutoCAD line types are to be used only (acadiso.lin). (Exceptions tothe rule should be limited.)To use the following line types are recommended. 1 2 3 4 5 CONTINUOUS HIDDEN CENTER DOT PHANTOMLine types shall be used as follows. Line Type Recommended Use Line Color Line Width continuous boundary of cut surface green 0.35 visible edges and visible contours from structural elements, boundary of cut continuous yellow 0.25 surface of small or little structural elements dimension line, dimension auxiliary line, continuous guide note line, walking line, boundary of red 0.18 detail figure, simplifying figure invisible edges and invisible contours hidden yellow 0.25 from structural elements center position of cutting plane green 0.35 center axes white 0.1 structural elements in front or above of dot yellow 0.25 cutting planeGeneral setting for line type scale refer to Section 3.5.2.3.5.10 HatchNote: x Do not explode hatch lines. x Do not delete hatch boundary line but put them on a help layer. Description Hatch Name Angle Line TypeMasonry ANSI31 0 By layerConcrete, reinforced ANSI33 0 By layerConcrete, not reinforced BETONUB 0 By layerSoil EARTH 45 By layerBackfill AR-CONC 0 By layerWood / timberSteel3.5.11 DimensionsUse the dimension style provided in the model drawing file (NCDD 50, NCDD 100, etc.). Do notchange the settings of these styles. If you need to create a dim style for another drawing scaleask for permission.Note that the drawing unit in MODEL space is metre. However, dimensions are in ‘mm’. (Thescale factor for measurement is set to 1000.)Study and Design Guidelines I-93
    • Part 3: Template Designs for Local Infrastructure STYLE NAME DIM 100 DIM 50 DIM 25 DIM 10Original Drawing Scale 1:100 1:50 1:25 1:10Overall scale 1000 500 250 100The height of dimension text is 1.5 mm in Layout. Dimension lines should have equal spacing.Do not overwrite dimension texts (No cheating).3.5.12 BlocksThe use of blocks is recommended for objects that are repeatedly used in drawings or projects.Block shall be created on Layer ‘0’.Purge unreferenced blocks before sending drawing files to design team members.3.5.13 External references (x-ref)The use of external references is useful especially for Mechanical and Electrical design.When attaching (or overlaying) external references use the Relative Path not the Full Path.Bind the x-reference; do not insert them.When exchanging drawings that make use of drawings from other design team members via x-ref, the reference drawings do not have to be exchanged.3.5.14 ViewportsViewport frames can be visible or invisible. Visible viewport frames are created on layer Z-viewport. Invisible are created on layer Z-viewport-offViewport zoom scales: Drawing Unit ‘m’ Drawing Scale Zoom Scale 1:1 1000xp 1:2 500xp 1:5 200xp 1:10 100xp 1:20 50xp 1:25 40xp 1:50 20xp 1:100 10xp 1:200 5xp 1:250 4xp3.5.15 PlottingUse color-depended plot style table files NCDD.ctb for all plotsStudy and Design Guidelines I-94
    • PART 4:MATERIALS, QUANTITIES AND COSTS I-95
    • Part 5: Materials, Quantities and Costs4 Materials, Quantities & Costs4.1 Project Cost EstimationAfter the project design preparation is completed, the Technical Assistant must estimate theproject cost by following the cost estimation guidelines in the PIM. To estimate the project cost,first estimate each of the outputs of the project and then sum all the estimated costs of theoutputs into a total for the output project. The total estimated cost of all outputs gives theestimated cost of the project.After estimating each project output cost the Technical Assistant will help the C/S chief to fill outthe form for the project output and project estimated cost and the project will proceed to bidding,all as described in the PIM.4.2 Tables of Quantities and Labor CostsFor infrastructure projects the PIM requires that the Technical Assistant refers to the ‘Table ofMaterial Quantities’ in this Technical Manual to find the quantities of materials that thecontractor will have to buy, and how much labor he will need. These tables appear at the end ofthis section (Tables 1 to 7)Note that the ‘unit quantities’ in the tables are for the complete construction task (the Net1quantity), not quantities of all the materials and labor used to complete the task (the Gross2quantity). The gross quantity for the construction task includes labor and waste materials,materials that will remain in the finished construction, and materials used temporally to completethe construction. The tables give the total including labor and material including waste materials to produce the unit quantity.For example, one cubic metre of concrete, shown on the drawing, means that all the things thatare needed to make one cubic metre of concrete and listed in the tables. These includes: x the materials in the concrete: cement, stone and sand; x materials that will be wasted in mixing the concrete; x wood and nails for the formwork; x labor to construct the formwork and to mix and place the concrete; and x equipment such as concrete mixer, vibrator and small tools.For another example, in Table 5 the unit quantity for steel bars is: x (1.0) tonne, but the quantity of steel used is 1.1 tonne which allows 0.1 tonne or 10% for waste; x in addition 10 kg of binding wire is allowed for fixing each 1.0 tonne unit quantity of steel; x the labor required per unit quantity is; o 1 day skilled labor, o 1 day semi-skilled labor, and o 6 days unskilled labor.4.3 Net QuantitiesThe gross quantities obtained from the tables of quantities and labor costs are obtained byfactoring the net quantity for wastage of the ingredients permanently incorporated into the works1 Net: remaining after all deductions (for waste and not permanently used).2 Gross: before any deductions (everything used).Study and Design Guidelines I-96
    • Part 5: Materials, Quantities and Costs(e.g. cement, sand and stone for concrete) and adding the temporary costs (e.g. the labor andthe materials used in formwork for concrete). The cost estimate is then obtained by multiplyingthe gross quantities by unit costs for the current cost database. The flow chart below illustratesthe process.Hence it is clear that it is necessary to first determine the Net quantities. Net Tables of Gross Cost quantities quantities quantities estimate and labor Cost databaseThe net quantities must be calculated from the output drawings. This is a standard constructionindustry task for infrastructure engineering and building work. It is usually done by the designerfor the bidding documents so that the contractors have an accurate indication of quantities, andso that the project owner can have an estimate of the cost before proceeding. It is done asecond time by the contractor (by the contractor’s staff with responsibility for quantity surveyingand purchasing) so that the purchase and delivery of materials to site can be organized. It willcommonly be done a third time as final measurement for payment3.For C/S Fund projects two situations exist: 1. Where a template design has been prepared for an output and loaded into the Project Generator, the quantity calculations have already been made and also loaded into the Project Generator. The cost estimate is produced automatically by the software accessing the current cost database and the ‘Detailed Cost Estimation Form for Construction Output’ is output for C/S Chief approval. 2. Where no template design has been prepared for an output, or where a ‘one-off’ output requires special or unique design drawings, then the Net quantities will have to be calculated. The cost estimate can then be prepared following the steps in the flow chart and procedures required by the PIM.When new template designs are prepared quantities should also be calculated and loaded tothe Project Generator as for existing templates.The following section gives further explanation and example of how the tables of quantities areapplied and how the cost estimate is prepared using the Project Generator.4.4 Cost Estimation Using the Project GeneratorThe quantity and cost estimation calculations for outputs with existing template designs areprepared as MS Excel Workbooks, each containing three linked spreadsheets. This isillustrated for the 2 x 0.8 m diameter pipe culvert shown as a design example for TechnicalForm T12 in Part 2 of this Technical Manual.3 It is conventional for the designer’s and final quantities to be measured Net, but the contractor obviously needs the Gross quantities otherwise there will be shortfalls of materials delivered to site. NCDD (and Seila previously) is different in that the Designer’s quantities in the bidding documents are Gross. The reasons for this are outlined in the PIM; the designer’s estimate is given to contractors as an aid to inexperienced small contractors to correctly make due allowance for all costs and profit when preparing a bid.Study and Design Guidelines I-97
    • Part 5: Materials, Quantities and CostsDetailed Calculation Spreadsheet A B C D E F G H I 1 1010305 Double pipe culvert 0.8m diameter 2 4 5 Row 2 6 Diameter of culverts (m) 0.8 7 Number of culverts per row 6 8 Length of each pipe (m) 1 9 Cover C (m) 0.510 Distance from market to site (km) 301112 Dimension Nº Description Number Units13 Length (m) width (m) Thickness (m) Surface (m²) Volume (m³)14 1 Blinding Concrete (1:3:6)15 slab under pipes 1 5.50 2.50 0.05 0.69 m³16 Wing walls and base slabs 2 -- -- 0.05 11.00 1.10 m³17 Concrete haunch 1 6.00 0.40 0.40 0.96 m³18 Total 2.75 m³1920 2 Concrete (1:2:4)21 wing wall 1 (Rectangular) 4 0.60 0.50 0.20 0.24 m³22 wing wall 2 (Trapezoidal) 4 1.10 2.90 0.20 2.55 m³23 slab under pipes 1 5.50 2.50 0.10 1.38 m³24 slab at sides of pipes 2 -- -- 0.20 7.78 3.11 m³25 cut off 1 (outside) 2 7.50 0.70 0.20 2.10 m³26 cut off 2 (inside) 2 2.50 0.40 0.20 0.40 m³27 head of wall 2 2.50 1.80 0.25 -0.79 1.86 m³28 Total 11.63 m³2930 3 Formwork31 slab under pipes 1 16.04 0.10 1.60 m²32 slab at sides of pipes 2 14.74 0.20 5.90 m²33 wing wall 8 1.10 2.90 25.52 m²34 wing wall 4 0.60 1.22 2.93 m²35 head wall 2 5.54 1.80 19.94 m²36 cut off 2 15.44 0.50 15.44 m²37 cut off 2 5.54 0.30 3.32 m²38 Total 74.66 m²3940 4 Gabion mattress 8 2.00 1.00 0.30 4.80 m³41 Total 4.80 m³4243 5 Geotextile filter 1 8.60 2.30 19.78 m²44 Total 19.784546 6 Soil Excavation47 From actual road EL to base slab 1 6.00 2.50 1.80 27.00 m³48 slab under pipes 1 6.00 2.50 0.20 3.00 m³49 Slab at sides of pipes 2 -- -- 0.20 7.78 3.11 m³50 cut off 1 (outside) 2 7.50 0.70 0.20 2.10 m³51 cut off 2 (inside) 2 2.50 0.30 0.25 0.38 m³52 Gabion 8 2.00 1.00 0.30 4.80 m³53 Slopes at both end of pipes 2 4.50 -- -- 2.43 21.87 m³54 Total 62.26 m³5556 7 Soil Backfill57 Pipes 1 5.50 2.50 0.50 6.88 m³58 Total 6.88 m³5960 Item Number Diameter Length(m) Total61 6 Pipes 12 0.80 1.00 12.006263 Item/Diameter D6 D8 D10 D12 Total64 7 Smooth bar (235 MPa) 43.64 298.46 342.10 kg65 8 Deformed bar 400MPa 268.41 142.79 411.20 kg6667 9 Wire 7.53 kg6869 10 Nail 8.96 kgAll the spreadsheets follow the same principles although their appearance is different. Thespreadsheets automatically make calculations using embedded formula and links between cellsand spreadsheets. Each spreadsheet is different and an understanding of embedded formula isnecessary to make changes or prepare new spreadsheets.In many cases a single spreadsheet is used for similar outputs. This is the case for the pipeculvert example which can be used for 0.6 m, 0.8 m, 1.0 m diameter and single, double or triplepipe culverts4. The required output code is selected from a drop down selection ‘Detailed4 For pipe culverts the range of options has been limited to ensure a logical progressive increase in hydraulic capacity; see Part 6 for further explanation. In terms of the quantity spreadsheet there is noStudy and Design Guidelines I-98
    • Part 5: Materials, Quantities and CostsCalculation Cell A2’. This the fills Cell B2 with the description ‘Double pipe culvert 0.8mdiameter’; Cell C5 with the number of rows ‘2’; Cell C6 with the diameter ‘0.8’.Drop down options are used for Cell C7, number of culvert rings per row ‘6’, Cell C9 cover ‘0.5’,and Cell C10 distance from market to site ‘30’ (used to calculate transport costs).The remainder of the ‘Detailed Calculation’ worksheet contains the dimensions taken from thedrawings and the calculations and summation of Net quantities for each work item, e.g. blindingconcrete, concrete (1:2:4), etc.The ‘Transport and Labor cost’ spreadsheet takes the Net quantities and factors these by theappropriate values extracted from the quantity and labor tables. The ‘Material Transport Cost’and its distance are read from the cost database and entered at Cell D2 on the ‘DetailedCalculation’ spreadsheet C10. These are used to calculate the transport related costs in thespreadsheet.The ‘Output Data’ spreadsheet provides the Detailed Cost Estimate Form for ConstructionOutput. It provides a summary of quantities of material, labor and transport costs by item.Transport and Labor cost Spreadsheet A B C D E F G H I J K12 Material Transport Cost (Tonne per Km) 800 Riels3 Transport Distance 30 km45 Weight/Unit Total Weight Transport Cost Unskilled Labor Semi-skilled Labor Skilled Labor No Description Unit Quantity6 (kg) (kg) (Riels) (days/Unit) (days/Unit) (days/Unit)7 1 Cement bag 88.26 50 4413.07 106,0008 2 Stone (10x20 mm) m³ 10.01 1700 17009.35 408,300 66 13 19 3 Stone (20x40 mm) m³ 2.47 1700 4203.68 100,90010 5 Sand m³ 6.24 1700 10606.51 254,60011 6 Formwork m² 74.66 10 746.56 18,000 4 19 712 7 Gabion mattress m³ 4.80 -- 0 00 0 0 013 8 Geotextile Filter m² 19.78 -- 0 00 0 0 014 9 Culvert pipe 0.6m diameter Number 12.00 250 3000.00 72,000 24 1 015 10 Smooth bars (235 MPa) kg 376.31 1 376.31 9,100 2 0 016 11 Deformed bars (400 MPa) kg 452.32 1 452.32 10,900 3 0 017 12 Wire kg 7.53 1 7.53 200 0 0 018 13 Nail kg 8.96 1 8.96 300 0 0 019 14 Soil Excavation m³ 62.26 -- 0 00 0 0 020 15 Soil Backfill m³ 6.88 -- 0 00 0 0 021 Total 40.82 980,300 100 34 10 limit on additional pipe sizes or combination which may be added (e.g. if ISO standard 0.9 m or 1.2 m diameter pipes are imported and used).Study and Design Guidelines I-99
    • Part 5: Materials, Quantities and CostsOutput Data spreadsheet A B C D E F 1 2 C/S Project 3 Detailed Cost Estimation Form for Construction Output Province: District: Commune: 4 Project Name: C/S Code: 1010305 5 Village: Description of Output: 6 7 Cost Estimation for 1 Unit of Output Nº Description Unit Quantity Price/Unit(R) Total (R) 8 9 1 Construction Materials10 1.1 Cement bag 88.26 19,600 1,730,00011 1.2 Stone (10x20 mm) m³ 10.01 100,000 1,000,60012 1.3 Stone (20x40 mm) m³ 2.47 52,000 128,60013 1.4 Sand m³ 6.24 23,200 144,80014 1.5 Formwork m² 74.66 16,650 1,243,10015 1.6 Gabion mattress m³ 4.80 200,000 960,00016 1.7 Geotextile Filter m² 19.78 20,000 395,60017 1.8 Culvert pipe 0.6m diameter Number 12 95,000 1,140,00018 1.9 Smooth bars (235 MPa) kg 376.31 3,120 1,174,10019 1.10 Deformed bars (400 MPa) kg 452.32 2,930 1,325,30020 1.11 Wire kg 7.53 8,600 64,80021 1.12 Nail kg 8.96 5,300 47,50022 1.13 Soil Excavation m³ 62.26 9,200 572,80023 1.14 Soil Backfill m³ 8.94 10,000 89,40024 Sub-Total of Construction Materials 10,016,6002526 2 Transport and Labor Cost Transport cost of materials and 2.1 Tonne 40.82 24,000 979,80027 equipments to the site Transport cost of equipments 2.2 Tonne 3.27 24,000 78,40028 from the site29 2.3 Unskilled labor day 100 15,000 1,500,00030 2.4 Semi-skilled labor day 34 20,000 680,00031 2.5 Skilled labor day 10 25,000 250,00032 2.6 Small Tools (% of labor cost) 3% 72,90033 Sub-Total of Tansport and Labor Cost 3,561,1003435 Sub-Total (Direct Cost) (1+2) 13,577,70036 Indirect Costs and Profit 10% 1,357,80037 Total Cost 14,935,5003839 Cost for Whole Output40 Description Unit Quantity Price/Unit Total (R)41 1010305 Double pipe culvert 0.8m diameter 1 1 14,935,500 14,935,50042 Market name: Haul distance: 30km434445 Date:…………….. Date:…………….. C/S Chief Technical Assistant46Study and Design Guidelines I-100
    • Part 5: Materials, Quantities and Costs Tables of Quantities, and Labor Costs Table 1 Concrete, mortars and plasters, sub-foundations Stone Labor Wood Skilled Semi- Unskilled Construction Task Cement Sand 10 x 20 20 x 40 40 x 60 Class 3 Nail skilled Description Unit Bags m3 m3 m3 m3 kg 3 Concrete (1:2:4) beams and columns m 6.7 0.5 1.0 0.1 1.0 5.0 Concrete (1:2:4) slab m3 6.7 0.5 1.0 0.1 1.0 4.0 Concrete (1:2:4) foundations m3 6.7 0.5 1.0 0.1 1.0 4.0 3 Concrete (1:2.5:4) floor m 6.2 0.55 0.9 0.5 0.5 4.0 3 Concrete(1:3:6) m 4.8 0.5 10 0.0 0.5 3.0 Concrete (1:5:10) m3 3.0 0.55 1.1 0.0 0.5 2.0 Formwork m2 0.01 0.12 0.1 0.25 0.05 Formwork for beams and columns m2 0.01 0.12 0.2 0.3 0.1 3 Mortar m 7.0 1.1 1.0 3.0 3 Sub-foundation gravel m 0.5 1.0 0.5 Pipe bedding m3 0.5 1.0 0.5Study and Design Guidelines I-101
    • Part 5: Materials, Quantities and Costs Tables of Quantities, and Labor Costs Table 2 Roof Materials Fibro Zinc Labor Fish scale Construction Task Square tiles roof tile 0.55 x 1.2 m 0.5 x 3 m Description Unit Tile piece Tile piece Sheet Sheet Skilled Semi-skilled Unskilled Dragon scale roof tile m2 70 0.1 0.1 0.1 Square tile roofing m2 16 0.1 0.1 0.1 fibro roof m2 2.5 0.05 0.05 0.05 2 Zinc roof m 0.9 0.05 0.05Study and Design Guidelines I-102
    • Part 5: Materials, Quantities and Costs Tables of Quantities, and Labor Costs Table 3 Walls and floor tiles Labor Hollow Solid Air White- Construction task brick brick Floor tile brick Stone Cement Sand wash 2 2 3 Semi- Description Unit piece piece m m m bag m3 kg Skilled skilled Unskilled Hollow brick piece 1.05 0.002 0.0003 0.003 0.002 0.006 Hollow brick wall 100 mm m2 52.5 0.1 0.016 0.15 0.1 0.32 Hollow brick wall 200 mm m2 105 0.2 0.032 0.3 0.2 0.64 Solid brick piece 1.05 0.0017 0.0003 0.003 0.002 0.006 2 Solid brick wall 100 mm m 105 0.17 0.026 0.3 0.2 0.5 Solid brick wall 200 mm m2 210 0.34 0.053 0.6 0.4 1.0 Plaster(1:2) m2 0.14 0.011 0.07 0.15 Plaster(1:6) m2 0.05 0.011 0.07 0.15 3 Masonry m 1.1 2.2 0.33 1.5 1.0 3.2 2 floor tile m 1.05 0.1 0.015 0.05 0.15 Paint walls m2 0.25 0.02 0.01Study and Design Guidelines I-103
    • Part 5: Materials, Quantities and Costs Tables of Quantities, and Labor Costs Table 4 Culvert Rings and Well Rings Labor Construction Task Ring Cement Sand Description Unit piece bags m3 Skilled Semi-skilled Unskilled Culvert ring 1000 mm diameter Ring 1 0.17 0.026 0.02 6 Culvert ring 500 mm diameter Ring 1 0.09 0.013 0.1 2 Culvert ring 600 mm diameter Ring 1 0.1 0.016 0.12 2 Culvert ring 800 mm diameter Ring 1 0.14 0.021 0.16 4 Well ring 0.5 m x 1 m Ring 1 0.17 0.026 0.25 0.25 0.25 Well ring 0.8 m x 1 m Ring 1 0.14 0.021 0.4 0.4 0.4 Well ring 1.2 m x 0.5 m Ring 1 0.084 0.012 0.5 0.5 0.5 Well ring 1 m x 1 m Ring 1 0.2 0.03 0.5 0.5 0.5Note:Labor quantities include for excavation of earth and backfilling.Cement and sand quantities are for mortar for sealing joinsStudy and Design Guidelines I-104
    • Part 5: Materials, Quantities and Costs Tables of Quantities, and Labor Costs Table 5 Structural Materials Labor Construction Task Quantity Wire Nail Description Unit Unit kg kg Skilled Semi-skilled Unskilled Steel bars tonne 1.1 5 1 1 6 Structural steel tonne 1.1 2 2 4 Wood Class 1 m3 1.1 6 14 20 2.4 3 Wood Class 2 m 1.1 6 1.8 3.4 4.5 3 Wood Class 3 m 1.1 6 1.8 3.4 4.5Study and Design Guidelines I-105
    • Part 5: Materials, Quantities and Costs Tables of Quantities, and Labor Costs Table 6 Standard Price for Earthwork Tasks Earthwork tasks Labor norm Cost before compaction Standard price Compaction Factor Description Unit Units/day Riel/unit Riel/unit 3 Excavate, place and shape earth m 1 0.50 1.3 0.65 3 Transport earth m x km - 0.12 1.3 0.16 Compact earth m3 - 0.30 1 0.30 Excavate Laterite m3 - 0.36 1.3 0.47 Place and shape Laterite m3 6 0.60 1 0.60 3 Compact Laterite m - 0.60 1 0.60 3 Transport Laterite < 20 km m x km - 0.12 1.3 0.16 Transport Laterite 20-35 km m3 x km - 0.11 1.3 0.14 Transport Laterite 35-50 km m3 x km - 0.10 1.3 0.13 3 Transport Laterite >50 km m x km - 0.09 1.3 0.12 3 Rock fill 200 mm m - 1.1 - Filter gravel m3 - 1.3 - Filter sand m3 - 1.3 - Grass m3 10 0.15 - 0.15NotesFor tasks carried out by machine, standard price = Cost/Unit x Compaction factorFor tasks carried out by labor, standard price is calculated:Study and Design Guidelines I-106
    • Part 5: Materials, Quantities and Costs Labor Cost = (Cost per labor day)/(Labor norm) Small tools cost = Labor Cost x 3%Standard Price = Labor Cost + Small Tools Cost + Materials CostStudy and Design Guidelines I-107
    • Part 5: Materials, Quantities and Costs Tables of Quantities, and Labor Costs Table 7 Other Tasks Shown on Drawings Labor Construction task Semi- Description Unit Other things included Skilled skilled Unskilled Afridev Pump Set spare parts and tools 2 Bolt Quantity Nuts and washers Column base Quantity Labor for excavation Concrete cover for well Quantity Concrete pipe 100 mm diameter m Doors and windows m2 All materials and labor to make door 0.1 0.4 Drilled borehole for well m All labor and equipment Piles 200 x 200 m Labor and equipment for driving piles PVC pipe 30 mm diameter m Fittings and glue PVC pipe 49 mm diameter m Fittings and glue PVC pipe 60 mm diameter m Fittings and glue PVC pipe 100 mm diameter m Fittings and glue Steel pipe 60 mm diameter m 0.1 2 Steel plate 5 mm thick m Steel plate 16 mm thick m2 Latrine Quantity All parts needed for toilet VN No 6 pump Set Rising main (49 mm PVC 12 m long), spare parts, tools. 1 Well head surround Number 1 Teacher desk Piece All labor and materials Student desks Piece All labor and materials White board Piece All labor and materialsStudy and Design Guidelines I-108
    • PART 5:STUDY AND DESIGN GUIDELINES I-109
    • Part 5: Study and Design Guidelines5 Study and Design Guidelines5.1 IntroductionThis section presents a suite of basic guidelines and procedures to help a non-specialist or non-technical person prepare a simple project design.The scope of C/S Fund infrastructure projects is broad since it includes topics such asfoundations and earthworks, buildings and structures, road engineering, resource and floodhydrology, groundwater wells, water supply, sanitation and drainage, irrigation and hydraulics.Most of these are specialist topics in their own right and even the most experiencedinternational infrastructure expert or engineer is unlikely to be good at every topic. Thereforeeveryone needs a little help sometimes and this section tries to provide it.5.1.1 LimitationsInfrastructure design can be very complex. It is very difficult to reduce design to a few simplerules and guidelines. There is always a risk that the conditions at the site are outside thesimplifying assumptions made for the guidelines. Yet it is equally difficult to instruct a non-specialist to spot these situations.The problem in the past under the Seila Program and similar work by The Social Fund, NGOsand others is that the complexities of design have been too daunting for the people on theground. Consequently they often ignored even basic and essential design procedures, took achance and unquestioningly built whatever the community asked for. Not every time but moreoften than not the infrastructure variously did not work as intended or broke very soon after itwas built, often because bad design choices meant it required maintenance and repair beyondthe means of the community.In fact for all the caution expressed above about the limitations of simple guidelines, in themajority of cases for simple infrastructure these guidelines, used correctly, will provide a safeand sustainable design. Most importantly the guidelines should avoid most of the big mistakesmade by not carrying out design at all.About 90% of the projects are for simple infrastructure. It is for this 90% that the guidelineshave been carefully chosen. The other 10% of projects are typically outside the guidelinesbecause they are unusual, have some complex issues, or are components of a larger projectthat needs a full design process; in such cases specialist advice and/or assistance should beobtained. Overall the objective of this approach is to improve the success rate of C/S Fundinfrastructure projects.5.1.2 Using the design guidanceThe design guidance is presented in the same order as the NCDD infrastructure group and sub-group codes. The codes are repeated in the titles.Important note and design decisions are incorporated into the Technical Forms. Most of theforms are linked to seperated sub-programs called ‘Applets’ which are already uploaded into theProject Generator, and need to be downloaded to carry out the design to fill into Technicalforms. The filled applets must be uploaded back into the Project Generator. The forms and/orapplets will automatically give guidance on the recommended design and dimensions ormaterials as appropriate. Guidance given in this way is highlighted in a box with a computer symbol throughout this design guideline.The form to which the advice applies is repeated in the titles.Study and Design Guidelines I-110
    • Part 5: Study and Design Guidelines You will only get the design guidance if you answer the questions, and the guidance will only be correct if the answers are honest – do not invent the answers.The basis of the guidance is explained. When the guidance is based on recommendations inan external reference this is listed as a footnote. Often these references are available from theInternet. This allows the user to find out more about the guidance, they may do this to improvetheir knowledge. There will also be occasions where it essential to use the references, e.g. ifthe project requires something beyond the coverage of an original template design.5.2 Transport Infrastructure: Group 101The design guidance for transport infrastructure is focused on roads and road structures. x Form T11 incorporates the advice for road earthworks and surface options. x Form T12 incorporates the advice for structures, particularly the selection of the correct structure type and size for drainage of rivers and streams across the road.5.2.1 Sub-Group 10101 and 10102: Roads: Form T11 Form T11 is incorporated with Applet T11 to advise on road surface option according to ADT and DCP values entered into the Applet. It is necessary that you complete this applet to get the advice before creating an output.Note: The definition of ADT and DCP and how to determine them are explained below.Design standardsRoad design is based on the MRD Interim Rural Roads Standards5. The guidance does notinclude National and Provincial roads which are the responsibility of the Ministry of Public Worksand Transport. It may be applied for residential roads within urban areas but is not intended foruse in heavily trafficked urban streets.Rural roads are categorised as follows: Tertiary District to District (T Roads) Sub-Tertiary 1 District to Commune (ST1 Roads) Sub-Tertiary 2 Commune to Commune (ST2 Roads) Sub-Tertiary 3 Commune to Village and Village to Village (ST3 Roads)MRD applies two design standards for tertiary/sub-tertiary roads based on traffic (traffic ismeasured as ADT, see the explanation of ADT below). Type A ADT = 201 to 2,000+ Type B ADT = 0 to 200The MRD standards for Type A and Type B are given in Table 5.1.Sub-tertiary roads in rural areas will mostly have ADT less than 200 for existing traffic so willinitially be Type B, but could become Type A if ADT increases above 200, as can happen aftera good road is built. If existing ADT is almost 200, if the road will join two busy centres or if itprovides access to growing businesses such as a plantation or factory this is a reason to designto Type A standards.5 Interim Rural Roads Standards for Tertiary and Sub-Tertiary Roads, Ministry of Rural Development 2006.Study and Design Guidelines I-111
    • Part 5: Study and Design GuidelinesTable 5.1 - Interim Design Standards for Tertiary/Sub-Tertiary Rural RoadsItem Designation Type A Type B Notes1 Composition of traffic (ADT) 201 ~ 2,000+ 0 ~ 200 Design Period Max flow in PCU2 Design Period 15 years 10 years3 Design speed (Km/hr) 70 / 60 / 50 60 / 50 / 40 Flat / Rolling / Mountainous4 Assumed ESA of commercial 1.0 0.4 If axle load surveys are not vehicle (6 tyres or more) possible5 Minimum radius of curvature 190 / 125 / 80 125 / 80 / 40 Flat / Rolling / Mountainous (metres) Unpaved surface6 Minimum radius of curvature 130 / 85 / 60 85 / 60 / 30 Flat / Rolling / Mountainous (metres) Paved surface7 Vertical alignment maximum (%) 4% 6% Steeper gradients should be Earth Road spot improved8 Vertical alignment maximum (%) 6% 6% 4% if rainfall 1,000 to Gravel Road 2,000 mm/year. Gravel unsuitable > 2,000 mm/year9 Vertical alignment maximum (%) 15% 20% Maximum 10% for thin Paved Road bitumen seals10 Horizontal sight distance 85 / 65 / 50 65 / 50 / 35 (metres) Flat / Rolling / Mountainous11 Maximum super elevation (%) 7% 7% Normally 3 – 4% is appropriate12 Extra widening / Increased width 0.5 metre 0.5 metre If radius of curvature <100 m at curves (metres)13 Constructed Carriageway 7% / 3% 7% / 3% Concrete Slab may be 2% Camber / Cross fall (%): Unpaved / Paved14 Shoulder plus Verge Width each 1.0 metre 1.0 metre Can be reduced in side of carriageway (minimum) mountainous areas with provision of passing bays on single lane roads. Minimum Type B roadway = 5.5 m15 Width of 5.0 metres 3.5 metres These are minima. If earth/gravel/Laterite/paved resources allow, wider surface carriageway (minimum) carriageway may be justified16 Initial constructed thickness of 200 mm 150 ~ 200 mm Use technical design Laterite / gravel surface compacted compacted guidelines. The suitability of (millimetres) gravel is adequately covered in the Rationale.17 Paved road pavement thickness Depends on Depends on Use technical design requirements requirements guidelines18 Elevation of road formation 500 mm above 500 mm above Sub-grade formation level (minimum) the HFWL the HFWL19 Embankment construction 150 mm (each) 150 mm (each) Depends on compaction Maximum layer thickness horizontal layer horizontal layer equipment used. All (compacted). earthworks must be compacted.20 Embankment side slope 1:2 ~ 1:3 1:2 ~ 1:3 (Vertical : Horizontal). Turfed finishing21 Side drainage ditches See technical See technical Trapezoidal shape, turfed. guidelines guidelines Scour checks or lined if gradient >4%22 Right of way (from Road Centre 15 15 Recommended line to each Side) (metres)23 Unobstructed clearance 7.0 metres 5.5 metres Headwalls extending above between backs of culvert embankment finished level headwalls at road surface level should be clearly marked (Minimum)24 Unobstructed carriageway width 3.5 metres 3.0 metres Suitable barriers and warning at single lane drifts and signing to be provided structures with width restriction and warning signs (Minimum)25 Berm width at embankment toe 2.0 metres 2.0 metres Recommended minimumStudy and Design Guidelines I-112
    • Part 5: Study and Design GuidelinesThe road widths recommended are: Tertiary District to District (T Roads) 6.0 m Sub-Tertiary 1 District to Commune (ST1 Roads) 6.0 m Sub-Tertiary 2 Commune to Commune (ST2 Roads) 5.0 m Sub-Tertiary 3 Commune to Village (ST3 Roads) 4.0 m Sub-Tertiary 3 Village to Village (ST3 Roads) 4.0 mThese widths are in some cases wider than the minimum in Table 5.1 but wider carriagewaysare permitted by the MRD standards.The design of the road depends on its location and alignment plus two key pieces of data. x Traffic (measured as ADT) x Strength of the ground (measured as DCP)Average daily traffic (ADT)For the purposes of rural road design, the prediction of future traffic flows will be based onsurveys of current traffic, and assessment of adjustments expected due to generated traffic,diverted traffic and future growth.The standard for Traffic Flow measurement is Average Daily Traffic (ADT), based on thePassenger Car Unit (PCU). The following table provides conversion factors for the variousvehicle types.Table 5.2 - Recommended PCU Conversion Factors for determination of road Type Equivalent Value in PCU’s for Rural Traffic Flow Type of Vehicle Calculations Passenger Car 1.0 Motorcycle 0.4 Motorcycle-trailer 0.6 Bicycle 0.3 Animal Cart 0.4 Light Vehicle / Van 1.0 Koyun 1.5 Medium Truck (6 tyres) 2.0 Heavy Truck (> 6 tyres) 2.5 Bus (> 4 tyres) 2.25 Mini-bus (4 tyres) 1.1 By completing the ‘Road Traffic’ (traffic count) boxes on Applet Form T11 the PCU values are automatically calculated and totalled. The required road design standard Type A or Type B is then shown, and need to be taken to filled into the Form. Remember, the ADT calculated from the traffic count is for existing traffic, you must decide whether to allow for future increase in traffic.There are some further questions on Form T11 to help make the decision about future traffic.Study and Design Guidelines I-113
    • Part 5: Study and Design GuidelinesDynamic Cone Penetration Test (DCP)The dynamic cone penetrometer (DCP) and the test it performs have been introduced forC/S Fund projects under NCDD; previously it was not required for projects under Seila Programalthough there was no prohibition on its use.The TRRL DCP (Dynamic Cone Penetrometer 40-T0012/A) has been in widespread use inCambodia for many years, particularly on MRD projects. The TRRL DCP is an instrumentdesigned for the rapid in-situ measurement of the structural properties of existing roadpavements constructed with unbound materials. Continuous measurements can be made downto a depth of approximately 850 mm or when extension shafts are used to a recommendedmaximum depth of 2 m. Where pavement layers have different strengths the boundaries can beidentified and the thickness of the layers determined.A typical test takes only a few minutes and therefore the instrument provides a very efficientmethod of obtaining information which would normally require the digging of test-pits. Normally,for road one DCP test needs to be made for every 500m length or 2000 m² area.Road pavement design is often based upon the CBR (California Bearing Ratio) of the ground orexisting road. Many people have tried to correlate DCP measurements with CBR but there aremany difficulties involved and it takes a lot of experience to use the results correctly if bigfoundations or major roads are involved. However for low-cost roads and structures the DCPcan be used as an indicator of CBR sufficient for most design decisions. Line 4 on Figure 5.1has been used in this design guidance. The recommend CBR for different types of pavementand pavement thickness have been back-converted to DCP so that the DCP measurements canbe used directly for design. The GPS coordinates and results in mm/blow are entered on Applet T11 for tests along the road alignment, as many tests as needed. The applet then calculates the 20 percentile DCP for all the tests (20 percentile is the value for which 80% of test sites are equal or stronger).If all tests give similar results then the 20 percentile value can be used for design. But if the soilstrength indicated by the test in some locations is much lower than the 20 percentile value thenyou should consider a stronger road design for these places.The 20 percentile DCP or individual tests results for locations with weak soil are used togetherwith the ADT to select the type of road and pavement thickness. If the road is at grade (groundlevel) then the DCP tests in the ground are used. If the road is on an existing embankment thenthe embankment must be tested. If the road will be built on new embankment, then theguidance assumes that this will be built with correctly compacted and suitable fill, and that it willtherefore be good for road pavement construction.Surfacing options Once the ADT and DCP data are entered on the first worksheet of Appet T11, suitable surfacing options are listed automatically including the thickness of pavement layers when these apply on the second worksheet of the form.All options are listed, including the more expensive paved road options. However unacceptableoptions are shown as unsuitable surfacing, e.g. earth roads are not suitable for ADT > 20 andwill be shown as unsuitable if ADT is 45.Study and Design Guidelines I-114
    • Part 5: Study and Design GuidelinesFigure 5.1 – Conversion of DCP to CBRThe basis of the design guidance incorporated into Form T11 for road types used by the C/SFund is as follows. Type: 1010101 Earth road Traffic: Suitable for ADT ” 20 ADT of which no more than 2 heavy trucks, buses or mini buses. Pavement: No guidance for DCP test results but > 15 mm/blow indicates the ground is too weak for at grade road construction, either the ground must be excavated and compacted or the road must be on compacted fill embankment.Study and Design Guidelines I-115
    • Part 5: Study and Design Guidelines Types: 1010102 Laterite road 1010103 Natural gravel road 1010104 Sand road 1010105 Crushed stone road Note: Unbound natural sand is unsuitable for road pavements but compacted stone dust used for roads in some parts of Cambodia is commonly referred to as a ‘sand road’. Traffic: Light traffic: Suitable for ADT ” 25 ADT of which no more than 2 heavy trucks, buses or mini buses. Medium traffic: Suitable for ADT ” 100 ADT of which no more than 21 heavy trucks, buses or mini buses. Heavy traffic ADT > 100 – Unpaved roads are unsuitable Pavement6: Light traffic: At grade or in cut: If DCP < 15 mm/blow pavement thickness 150 mm. If DCP = 15 to 32 mm/blow print pavement thickness 200 mm. If DCP > 32 mm/blow print pavement thickness 250 mm but also consider other surface. On embankment: Pavement thickness 200 mm Medium traffic: At grade or in cut: If DCP < 15 mm/blow pavement thickness 250 mm but also consider other surface If DCP = 15 to 32 mm/blow print pavement thickness 300 mm but also consider other surface If DCP > 32 mm/blow prints pavement thickness more than 300 mm but also consider other surface. On embankment: Pavement thickness 300 mm but also consider other surface. Type: 1010201 Dressed stone road Traffic: Not a constraint for use for rural or residential road. Pavement7: Stone layer: Stone thickness for all uses not less than 150 mm Sand sub-base layer: Stone shall be bedded on a sand layer not less than 50 mm Type: 1010202 Mass concrete road Traffic: Not a constraint for use for rural or residential road. Pavement8: Concrete slab: Slab thickness 200 mm Sand road-base layer: Sand road-base thickness 50 mm Sand sub-base layer: Sand sub-base thickness 300 mm Type: 1010203 Steel-reinforced concrete road Traffic: Not a constraint for use for rural or residential road. Pavement: Concrete slab: Thickness 150 mm6 PIARC, TRL & Intech Associates. Rural Road Surfacing: Surface Options – Gravel, Ref: RR Surface 3h, June 2003. (Note: Pavement thicknesses adopted are for high rainfall more than 1,500 mm/year with long dry season).7 Gourley Dr C et al. Low Cost Road Surfacing (LCS) Project, LCS Working Paper No12 – Paving the Way for Rural Development & Poverty, CSIR, TRL, Intech Associates, September 2002.8 Azam A I et al. Low Cost Road Surfacing (LCS) Project, LCS Working Paper No7 – Bamboo Reinforced Concrete Pavement Road Construction in Cambodia, ILO, Intech Associates, June 2002.Study and Design Guidelines I-116
    • Part 5: Study and Design Guidelines Sand road-base layer: Thickness 50 mm Sand sub-base layer: Thickness 300 mm Type: 1010204 Mesh-reinforced concrete road Traffic: Not a constraint for use for rural or residential road. Pavement: Concrete slab: Thickness 150 mm Sand road-base layer: Thickness 50 mm Sand sub-base layer: Thickness 300 mm Type: 1010205 Double Bituminous Surface Treatment (DBST) road Traffic: Not a constraint for use for rural or residential road. Pavement: Surface: Two layers of stone chippings. Road-bas: Thickness 75 mm Sub-base: Thickness 225 mm Type: 1010206 Single Bituminous Surface Treatment (SBST) road Traffic: Not a constraint for use for rural or residential road. Pavement: Surface: Two layers of stone chippings. Road-bas: Thickness 75 mm Sub-base: Thickness 225 mm Type: 1010207 Asphalt concrete (AC) road Traffic: Not a constraint for use for rural or residential road. Pavement: Surface: NOT YET DECIDED. Road-bas: Thickness 75 mm Sub-base: Thickness 225 mm Type: 1010208 Brick paved road Traffic: Not a constraint for use for rural or residential road. Pavement9: Brick layer: Brick thickness for all uses not less than 70 mm Sand sub-base layer: Bricks shall be bedded on a sand layer not less than 50 mmRoad Suface and Pavement Thickness The road surface must be chosen and its thickness must be entered as recommended by Applet T11.Form T11 requires you to choose road surface and enter pavement thickness. This is deliberatewith the intention of permitting selection of a non-recommend thickness. For example a 200mmLaterite road may be chosen even when Applet T11 suggests only 300mm laterite road typesare suitable. This allows the project to proceed even if there is insufficient money for therecommended road type and pavement thickness. The form provides a record that designadvice was not followed and this may require you to later justify the decision.The questions on Form T11 for Materials for Construction should be considered when selectingthe type of road, e.g. if Laterite has to be hauled 100 km it is probably not the best choice, eitherin terms of initial construction, or in terms of maintainability.5.2.2 Sub-Group 10103 to 10108: Road Structures: Form T12This design guidance relates to road structures that provide drainage across the road andincludes all types of bridges, culverts and low-level crossings.9 Gourley Dr C et al. Low Cost Road Surfacing (LCS) Project, LCS Working Paper No12 – Paving the Way for Rural Development & Poverty, CSIR, TRL, Intech Associates, September 2002.Study and Design Guidelines I-117
    • Part 5: Study and Design Guidelines There must be one T12 form for each road structure. The form will attach with it an Applet T12 used to obtain advice on structures to be chosen before creating a project. If catchment area can be defined, it is a must to use the applet.Note:Explanation on questions to be answered in the applet can be found from the Hydrologyand hydraulic capacity section below.Design standardsTemplate designs for culverts provide a minimum unobstructed width of 5.5 m between thebacks of culvert headwalls at road surface level. This complies with the MRD Design Standardsfor Type B roads (Table 5.1). For Type A roads the width should be 7.0 m. Pipe culverts canbe made wider by adding extra pipes. For box culverts width between headwalls of the boxsection walls and slabs will have to be increased and will require more concrete and reinforcingsteel. Extra width will also be needed for a high embankment because the bottom of the slopesis farther apart.Template designs for concrete bridges provide an unobstructed width of 4.5 m which isconsistent with contemporary MRD road projects. A wider roadway will require a modifieddesign which will require the assistance of a qualified structural engineer. The particularconcern is the hanging beams which support the bridge; these also provide the bridge parapets.The beam reinforcement would have to be increased for a wider roadway. Also the abutmentwalls and deck slab will have to be increased in width and will require more concrete andreinforcing steel, as well as extra piles for piled foundations.Concrete bridges are designed for AASHTO HS 20-44 20 tonne loading.The wooden bridge template design is unchanged from the Seila Template and has a notional5 tonne loading.Steel bridges including Bailey Bridges are not covered by this design guidance and specialistadvice should be sought on an as-needed basis.Road classification The road classification, standard and width are entered manually, but if Form T12 has been generated by a Form T11 then the information is entered the same as the road form.If the project is for an isolated road structure then the road classification, road standard androad width questions will have to be answered. It is not necessary to conduct a traffic count todetermine the road standard; judgement can be used to answer this question.Scope of worksThe questions relating to the scope of works focus on the description, sizes, condition andcauses of damage to existing structures. It is important to complete this information in order tounderstand the problems at the site, e.g. a culvert that collapsed due to scour is a very definiteindication that the structure was too small for the flow, and/or that the new structure requiresscour protection. Pay attention to the questions asked and think about the causes of the problems.Material available for constructionThese questions indicate whether there will be problems complying with the Specification, e.g. ifgravel will come from a river then it will be rounded and unsuitable for concrete.Soils and Dynamic Cone Penetration Test (DCP)Information on soils and DCP tests is needed to consider whether the foundations will be strongenough to support the structure, also whether they will be particularly vulnerable to erosion andscour.Study and Design Guidelines I-118
    • Part 5: Study and Design GuidelinesThe DCP results are used in the same way as described for road projects. One test may besufficient for a small culvert but for large culverts and bridges it is recommended to check eachbank and the water channel, as many times as necessary.For concrete bridges it is recommended to have an investigation borehole at each abutment. Itis recognised that this adds to the cost but a bridge is a big investment. If the bridge is on piledfoundations the risk of not sinking an investigation borehole is reduced.The template designs for concrete bridges are for single spans and do not require anintermediate pier. However, if multiple spans are required then investigation boreholes shouldalso be sunk in the river bed as close as practical to each pier location.Hydrology and hydraulic capacityThe size of a bridge, culvert or low level crossing and any protection works must be chosen forthe flow and flood conditions at the site. Deciding flow and flood conditions can be difficultwhere the land is very flat and/or where the natural drainage has been altered by roads,embankments and irrigation systems.Two situations occur: x flow at the structure comes from a single catchment; or x the structure is in a flat and/or flood area where water can come from distant and large catchments.The design guidance is focused on being able to define the catchment and its characteristics.This is described first below. The guidance that applies for large flat and flood areas follows. By answering a few simple questions about the catchment on Applet Form T12 you will automatically be told the estimated peak flood flow, advised on the most suitable size of structure, and told the exit velocity for flow from the structure.What do we mean by a catchment?The catchment area at a structure is the area of land from which water (runoff) flows to thatstructure when there is rain. (If you collect rainwater from a roof, the catchment is the area ofland kept dry by the roof).Figure 5.2 – Example of a catchment It is easier to understand the concept of catchment area where the land is hilly and there are streams in every valley. When there is rainfall, the stream that the water flows to is controlled by the slope of the land, e.g. if 30% of the land where the rain falls Water divide slopes towards stream A, then it will receive 30% of the rainfall, the remaining 70% will flow to other streams. The line separating the catchment of stream A from the other streams is the water divide where water Catchment area flows away in two directions into adjacent A = 5.8 km2 catchments. This is a line drawn following the highest ground between the catchments. Therefore, catchment boundaries are usually defined on contoured maps such as the example at Figure 5.2. Sometimes however, particularly when the land is very flat, it is not the contours that form a catchment boundary but an artificial boundary such as a field bund, track or road embankment that intercepts flow Culvert and sends it in a different direction and into a different catchment than would be the case for the natural undeveloped landscape.Study and Design Guidelines I-119
    • Part 5: Study and Design GuidelinesCatchment boundaries cannot cross a stream. Every plot of land must be in the catchment ofone stream or another, if you draw the catchment divides between several streams and haveany area of land left over where you do not know where the water flows, it means you havemade a mistake and need to correct the boundaries.Factors that control catchment runoffThe main factors which control the size and time of runoff are: x Catchment area x Rainfall x Land slope x Vegetation x Soils x Catchment shape x Available (flood water) storage in lakes, swamps and rice paddies x Settlements (villages, towns and infrastructure)The above list is in declining order of importance, although the order may sometimes change,for example a large lake would be near the top of the list.The interrelationships between these factors that control the peak runoff are extremely complex,and despite years of global research and observation, the estimation of runoff remainsapproximate and uncertain. Fortunately, most catchment characteristics change only veryslowly with time. Their interaction is therefore reflected in the size, shape and type of river orwaterway. It is as important to visit the site and look at the channel and land upstream anddownstream of the structure; as it is to consider the other listed factors.Where the river channel or waterway has already been spanned by a bridge or culvert, thelength of time that the structure has successfully resisted being washed away and itsperformance during floods will provide useful information for design. It can be argued that if thestructure has survived without damage it is already the optimum size for the site, eliminating theneed for further hydrological studies. One flaw in this argument is that many unimproved roadsare at low-level on little or no embankment and flood flows can then easily bypass a structurewithout causing major damage. An improved road on a raised embankment will completelychange this situation (Figure 5.3). The key point is that field investigation must be thorough, and the conclusions made must be well considered, in order to avoid mistakes.Figure 5.3 - The difference between flow bypassing a culvert where the road is at low-level orwhere it is on embankment. Overland flow Road Culvert Low-level road Road on embankment Flow Flow Overland flow too large for culvert Overland flow too large for culvert floods can bypass and flow over low-level upstream of high embankment until it road with minimal damage. flows across the road with risk of erosion, scour and embankment breach.Study and Design Guidelines I-120
    • Part 5: Study and Design GuidelinesMethods of flow estimationThe recommended method of flow estimation is the Generalised Tropical Flood Model10(GTFM). This method has been used quite often in Cambodia, usually by consultants, the firstuse was probably for the emergency flood projects at MPWT in 2001 and subsequently projectsunder MRD and MOWRAM. It gives good results for small to medium catchments up to andlarger than would require the culvert and small bridge template designs accompanying thisdesign guidance. The method takes into account all the factors that affect catchment runoff andthe information can usually be obtained from available maps. The method is also easy to use ina spreadsheet or as an applet.The alternatives to the GTFM include: x Rational method x US Soil Conservation Service (Curve Number) Method x SWAT Model.The Rational Method is intended for urban catchments and because of the simplifyingassumptions that apply only for these conditions it should not be used for rural catchmentmore than 0.8 km2 area otherwise it grossly overestimates flow11. Because the method is sosimple to use it is used mistakenly by many people. The GTFM can be used for smallcatchments so there is no need to consider the Rational Method.The US SCS Method is quite complicated to use correctly and requires catchment data notgenerally available directly from maps. Since it is no more reliable than the GTFM it has notbeen used.The SWAT model is a river basin, or catchment, scale model developed for the United StatesDepartment of Agriculture Agricultural Research Service and used by the Mekong RiverCommission. It is intended for water resource planning rather than peak flow prediction,requiring the software and knowledge how to use it. These factors make it unsuitable forroad structure design. The next few sections give the basic theory for using the GTFM, it is good to understand these but it is not essential provided the questions on Form T12 are answered correctly.RainfallAll the methods of flow estimation discussed above including the GTFM are known as rainfall-runoff models, that means a ‘design’ rainfall is assumed for the catchment and the models takeinto account the factors that determine what percentage of the rain will appear as runoff at thestructure, what percentage stays in the catchment in the soils, or is used by vegetation, etc, andalso the timing and size of the peak flow at the structure.For road structure design it is necessary to know the rainfall intensity in mm/hr over differentdurations between 5 minutes and 24 hours, and for different return periods. This informationcan be obtained by measuring rainfall with a continuously recording rain gauge over a period ofnot less than 10 years. In Cambodia such a record only exists for Phnom Penh InternationalAirport (Pochentong) for a period of 16 years, although the national coverage of rain gaugesand records is fairly good these are all daily (24 hour) rain gauges. This is overcome by usingthe method of Rainfall Ratios and converting the 24 hour rainfall to shorter duration by applyingindices derived by back analyses of the record at Pochentong. This technique is described in10 Watkins L H and Fiddes D. Highway and Urban Hydrology in the Tropics, Pentech Press, London, 92-100 (1984).11 Chow V T. Handbook of Applied Hydrology, McGraw-Hill Co, London (1964).Study and Design Guidelines I-121
    • Part 5: Study and Design GuidelinesWatkins and Fiddes12. The indices vary from region to region according to rainfallcharacteristics but the rainfall at Phnom Penh is representative of that for lowland Cambodia.To avoid the need to obtain rainfall records and use different rainfall charts for each location thedesign guidance is based on long term rainfall records at 21 locations covering the mostpopulace areas of the country. The 80 percentile values for these data are shown in Figure 5.4and Figure 5.5 as rainfall rainfall-intensity-duration and total rainfall curves respectively forreturn periods 1 in 2.3313, 5, 10, 25, 50 and 100 years.By default the design guidance applied by T12 uses these rainfall curves for design becausethey are appropriate for most places in Cambodia. However, the form has the option to apply33% greater rainfall in known high rainfall areas.Return periodThe larger and more expensive structures are designed for a longer return period rainfall/flowthan the smaller ones; the logic is that it is easier and cheaper to replace a small structure thana large one. This approach is used in all countries and is applied by MRD for road structures.This design guidance applies the following standards.Table 5.3 – Road structure design return period for peak flow Structure type Design return period TR Bridge •10m 1 in 50 year Small bridge <10m 1 in 25 year Large box 1 in 25 year Small box 1 in 10 year Low level crossing 1 in 10 year Pipe 1 in 10 yearGTFM The advice on use of the GTFM that follows is applied automatically by answering all the questions on T12. This is explained in Design procedures below.The Generalised Tropical Flood Model is expressed by the formula: C A u P u A u F u ARF QR 360 u TB Where QR : peak flow of return period R years (m3/s). R: return period (years). CA : is the percentage runoff coefficient. P: is the design storm rainfall (i.e. total rainfall in mm not intensity in mm/h) of hydrograph base time (TB hours). A: is the catchment area in km2. F: is the peak flow factor to convert the average flow generated by the model to peak flow, F=2.5 is suitable for structures in Cambodia. ARF : is the area reduction. TB : is the hydrograph base time (hours).12 Watkins L H and Fiddes D. Highway and Urban Hydrology in the Tropics, Pentech Press, London, 92-100 (1984)13 A return period of 1 in 2.33 years is the mean annual peak rainfall.Study and Design Guidelines I-122
    • Part 5: Study and Design GuidelinesFigure 5.4 - Rainfall-intensity-duration curves used for design guidance 80 Percentile Rainfall-Duration-Intensity 1000 Intensity (mm/hour) 100 1 in 2.33 Year 1 in 5 Year 1 in 10 Year 1 in 25 Year 1 in 50 Year 10 1 in 100 Year 1 0.01 0.10 1.00 10.00 100.00 Duration (hours)Figure 5.5 - Total rainfall curves used for design guidance 80 Pencentile Rainfall Totals 250 200 Total rainfall (mm) 1 in 2.33 Year 150 1 in 5 Year 1 in 10 Year 1 in 25 Year 100 1 in 50 Year 1 in 100 Year 50 0 0.00 3.00 6.00 9.00 12.00 15.00 18.00 21.00 24.00 Storm duration (hours)Study and Design Guidelines I-123
    • Part 5: Study and Design GuidelinesThe peak flow QR is the flow used to select the structure type and size. The hydraulic capacityis chosen to pass this flow.The return period R is selected for the proposed structure (Table 5.3). If the structure requiredis different to that originally proposed it may be necessary to restart the calculation (by changingthe proposed structure at the beginning of the form) until the return period is correct for thestructure type and size.The percentage runoff coefficient CA is express by the formula: CA C S u CW u C L Where CS : is the standard value of contributing runoff coefficient, from and is dependant on Soil Class I , from Table 5.4 and Slope Class S , from Figure 5.6. CW : is the catchment wetness factor which is dependent on soil moisture recharge (SMR). Because Cambodia is within a wet zone (SMR > 75 mm) the value adopted should always be 1.00. CL : is the land use factor from Table 5.6.Soil Class I is selected from Table 5.4.Table 5.4 – Soil Class ISoil characteristic Description Soil class (I)Impermeable rural Rock surface 1Impermeable settlements Paved urban, village centre 1 Clay soils with high swelling potential; shallow soils over largely impermeable layer, very high water 2Very low permeability table.Flooded paddy Mostly flooded paddy in wet season 2 Impeded drainage and areas of flooded paddy in wetLow to very low permeability season 2.5Low permeability Drainage slightly impeded when soil fully wetted. 3Low to fairly permeable Deep soils but areas of flooded paddy in wet season 3.5 Deep soils of relatively high infiltration rate whenFairly permeable wetted. 4 Soils with very high infiltration rates such as sands,Very permeable gravels and aggregated clays. 5Slope is measured along the path taken by the water, therefore this must be along the length ofthe stream or flow path, not the straight line distance but the distance allowing for twists andturns of the stream, or the valley if there is no stream. Slope must also be representative for thecatchment. For this reason it is measured between two point 10% and 85% distance up thecatchment measured from the structure. This eliminates error due to a steep rise at the top ofthe catchment, a situation which is common in many places in Cambodia where steepmountains are beside flat plains. Hence slope is calculated from the formula. Elv85  Elv10 Slope u 100 0.75 u L Where Elv85: is the elevation 85% of the distance up the catchment from the structure (m) Elv10: is the elevation 10% of the distance up the catchment from the structure (m) L: The distance between the structure and the catchment boundary measured along the stream and the flow line beyond the stream to the boundary (m) 100: Conversion to percent.Slope Class S is read off Figure 5.6.Study and Design Guidelines I-124
    • Part 5: Study and Design GuidelinesFigure 5.6 – Slope Class S Catchment slope classification 30 25 Average catchment slope (%) 20 15 10 5 0 1 2 3 4 5 6 Slope Class (S)Having determined the soil class S and slope class I the standard value of contributing runoffcoefficient CS is calculated from the following formula. Values for CS are also shown in Table5.5. CS 53  12 I  8S Where CS: is the standard value of contributing runoff coefficient. I: is the Soil Class. S: is the Slope Class.Table 5.5 – Standard value contributing runoff coefficient CS Soil Class I Slope Class S 1 2 3 4 5 1 49 37 25 13 1 2 57 45 33 21 9 3 65 53 41 29 17 4 73 61 49 37 25 5 81 69 57 45 33 6 89 77 65 53 41Land use class CL is looked-up from Table 5.6.Study and Design Guidelines I-125
    • Part 5: Study and Design GuidelinesTable 5.6 – Land Use Class CLLand use characteristics Catchment type CLSettlements Urban or village centre 1.00Bare soils Largely bare soil 1.50Cultivated Intensive cultivation 1.50Grassland Grass cover 1.00Dense vegetation Dense vegetation (particularly in valleys) 0.50Forest thin soil Forest: (a) shallow impermeable soils 1.00Forest steep slopes Forest: (b) very steep (S5, S6) permeable 0.67 soilsForest other Forest: (c) deep soils and gentle slopes 0.33The design rainfall P is obtained from Figure 5.5 for the calculated value of TB (see below) andthe selected return period.If you have reason to think the structure is in a high rainfall area then it is recommended that Pbe increased by 33%. This is done automatically by selecting the high rainfall option on FormT12.The catchment area A is measured from the map.The peak flow factor F converts the average flow generated by the model to peak flow, F=2.5 isa suitable peak flow factor for structures in Cambodia.The area reduction factor ARF is introduced to take into account that rainfall at any given instantvaries over the catchment. In simple terms, the average rainfall intensity at any instant for acatchment will be less than the rainfall measured at a single point in the catchment, and thedifference increases with increasing size of catchment. Therefore, this is not significant forsmall catchments but becomes so as catchment size increases. The relationship adopted forARF is suitable for the convective rainfall14 that occurs in Cambodia: ARF 1  0.04T 0.33 A 0.50 Where T: is duration in hours A: area in km2This equation applies for storms of up to 8 hours duration. For longer durations on largecatchments the value calculated for T = 8 hours is used.The hydrograph base time TB can be thought of as being made up of three components: thestorm duration, the time taken for the surface runoff to drain into the stream system; and theflow time down to the structure.Base time TB is expressed by the formula: C u A 0.5 TB  TS S2 Where C: a constant, which is 30 for Cambodian catchments. A: the catchment area (km2). S: the Slope Class S. TS : the surface cover flow time from Table 5.7.14 Convective rainfall occurs where there is low pressure and air movement is mostly vertical. Evaporation is high early in the day and moisture is carried high by vertical currents. Rainfall occurs usually in the afternoon or early evening.Study and Design Guidelines I-126
    • Part 5: Study and Design GuidelinesTable 5.7 - Surface cover flow time TSCatchment type TS (h)Arid zone 0.0Poor pasture / scrub (large bare soil patches) 0.0Good pasture 1.0Cultivated land (down to river bank) 2.0Forest (a) shallow impermeable soils 2.0 (b) very steep (S5, S6) permeable soils 2.0 (c) other 12.0Swamp filled valleys 20.0The GTFM equation assumes a catchment of average shape with length to width ratios (L/W) ofbetween 2 and 6. For fan-shaped catchments (L/W = 1) the design flood is increased by 50%.For very long catchments (L/W = 20) it is halved.Structures in flat flood areasIf a structure is in a flood plain or on flat land that floods every year it may be impossible todecide the catchment. In fact, if the flood is deep then the catchment divides may be underwater and be merged with the catchments of adjacent structures along the road. The structureswill then work together.In terms of the structure the worst condition that could cause it to collapse is that water levelsare high on one side of the road and low on the other. Under these conditions water will flowvery fast through the structure driven be a difference of water levels of maybe 1 or 2 m.Eventually the water levels upstream and downstream will become about the same so that thehead difference is no longer significant; this may take a few hours or a few days, depending onthe situation, or until the flood goes away.In these conditions, if the structure is too small to pass the flood quickly, water level upstream ofthe structure may continue to rise until water overtops the adjacent road embankments. Therate of increase in upstream water level after this will be small because most of the water willflow over the road. Hence the worst case that may damage the structure is with water on oneside at road level, and the other side at ground level. The template designs for concreteculverts and bridges have been designed for this condition. The scour protection, particularlythe gabion mattress has been chosen to withstand the flow velocity under this condition and toprevent the collapse of the structure. It is important to understand that even though the template designs can withstand extreme flood conditions; this is no excuse for building a too small structure. Most importantly if the road embankment is overtopped it will be damaged, particularly if the road is unpaved. The flood water will probably break through the embankment (breach the embankment) leaving gaps in the road. As is shown by Figure 5.3 raising a road embankment can block flood flow; whereas water can freely flow over a road at about ground level, a road embank creates a dam which forces all the flow through the road structures. You must think whether building the road and structures will make flooding worse or whether it will cause damage to the new road and structures; if you think it will you must change the design and may need specially advice and help.Design procedure You can complete all the above design simply by filling correct answers on the Applet T12.Study and Design Guidelines I-127
    • Part 5: Study and Design GuidelinesForm T12 incorporates applet T12 that completes the recommended hydrological and hydrauliccalculations. You need to answer a series of questions in the applet, then you need to copy thenecessary responses and recommendations directly to the form. The questions are listed below together with explanation of the reason for the questions and advice on how to answer.What type of structure is envisaged?Choose the type of structure you expect to The applet needs this information to selectprovide. the correct return period, Table 5.3.Can catchment be defined?This question decides whether the flow to If the catchment cannot be defined then thethe structure is from a large flat flood area form prints ‘Flow estimation not possible,or a catchment that can be measured. design for road overtopping’ and no further questions appear. If you get this response you should seek specialist advice because the project proposal may not be viable and sustainable.What is the catchment area in km2?Used by the applet for calculations. Measured from Topo MapWhat is the length of catchment in metres?Used by the applet for calculations. Measured from Topo MapWhat is the land elevation 10% up catchment?What is the land elevation 85% up catchment?Used together with the length of the The most reliable way to measure elevationcatchment to calculate the catchment is by topographical survey. Hand held GPSslope. The applet then selects the Slope cannot be used because the elevationClass S. measurement shown is only approximate. Often it is possible to get acceptable slope measurements from maps. For example if the catchment is between 10 m interval contours 4.0 km apart then the land slope is (10 ÷ 4000) x 100 = 2.5%. You adjust the answers so that the program calculates this slope. Be careful using spot heights on maps, they often show roads level and are not correct for general land level and slope.What are the catchment soil characteristics?Used by the applet to select Soil Class I. You chose from the selection in Table 5.4, the table provides more detailed description for guidance. Be careful to choose soils representative for the catchment because the soils at the road may be different.What are the catchment land use characteristics?Used by the applet to select Land Use You chose from the selection in Table 5.6,Class CL. the table provides more detailed description for guidance. Be careful to choose for land use in the catchment not that beside the road.What are the catchment surface cover flow time characteristics?Used by the applet to select Surface You chose from the selection in Table 5.7.Cover Flow Time TS.Study and Design Guidelines I-128
    • Part 5: Study and Design GuidelinesIs location a normal or very heavy rainfall location?The applet will factor-up the rainfall by You use this option if you believe there is33% if you answer that it is a heavy unusually high rainfall, maybe because therainfall location. road is in a mountain location, because the streams are big, or local people have told you so. For all other areas chose ‘normal’.Then you need to copy the following calculation results from Applet T12 to Form T12: x Design(peak) flow in cubic metres per second x A suitable structure x Velocity at the structure outlet in metres per second.Does this match the structure entered at method selection?The program asks this question as a If the structures are different you may needcross-check that the recommended to repeat the process by starting with thestructure is the same as you proposed. recommended structure. This is particularly necessary if the recommended structure needs to be designed for a different return period.Structure flow capacity and velocityThe flow and therefore the exit velocity of a structure depends on the relative water levelsupstream and downstream of the structure. The flow condition that has the lowest designdischarge is different to that which has the highest exit velocity (because the latter is for thehighest design discharge). The design guidance generated by Form T12 for flow uses safeassumptions for the condition giving the lowest flow, and the condition giving the highestvelocity, these being the worst cases for design.There are six recognized flow types, strictly these apply for culverts but there is no differencehydraulically between a box culvert and a small bridge. A primary reference is Bodhaine15.The flows, velocities and associated flow types applied by the applet are listed in Table 5.8.The flow types are defined as follows: Type A: Part full, critical depth at inlet Type E: Full, wall friction, backwater from downstream Type F: Full, wall friction, critical depth at outletNote that there is a progressive increase in capacity for the structures listed in Table 5.8. Theseare the preferred structures. For example you could use 4 x 0.6 m pipes for a flow of 1.7 m3/sbut it is better to use a single 1.0 m pipe which will provide 1.80 m3/s capacity.In the interests of ease of maintenance and to reduce blockage it is good practice not to usepipes smaller than 1.0 m diameter. Also note that it is acceptable (and in many countries alsorequired for environmental reasons) to set the bottom of the pipe 100 to 200 mm below thestream bed, the reduction in capacity is negligible but it minimises the need to ramp a road overa culvert.Wooden and steel bridgesForm T12 does not specifically recommend wooden or steel bridges. This is because they willusually be temporary structures which will in the future be replaced by a concrete bridge orlarge box culvert. However Form T12 can still be used to estimate the peak flow at the bridge.Table 5.8 can even be used as a rough guide to the required length of a wooden or steel bridge;it can be seen that each metre of full height span provides about 8 m3/s of flow capacity.15 Bodhaine GL. 1968, Measurement of Peak Discharge at Culverts by Indirect Methods: U.S. Geol. Survey Techniques Water-Resources Inv., book 3, chap. A3, 60 p, 1968.Study and Design Guidelines I-129
    • Part 5: Study and Design GuidelinesTable 5.8 – Design flows and velocities at road structuresStructure type and size Design flow Flow type Design Flow type capacity velocity (m3/s) (m/s)Single 0.60 m pipe 0.50 A 2.42 FSingle 0.8 m pipe 1.03 A 2.80 FSingle 1.0 m pipe 1.80 A 3.13 FDouble 0.8 m pipe 2.07 A 2.80 FDouble 1.0 m pipe 3.61 A 3.13 FTriple 1.0 m pipe 5.41 A 3.13 FSingle 2.0 mW x 1.5 mH Box 8.23 E 3.93 FSingle 3.0 mW x 1.7 mH Box 14.00 E 4.06 FSingle 3.0 mW x 2.0 mH Box 16.47 E 4.25 FDouble 3.0 mW x 2.0 mH Box 32.95 E 4.25 F5.0 m span bridge 41.20 E 4.84 FTriple 2.0 mW x 2.0 mH Box 49.42 E 4.25 F7.5 m span bridge 61.80 E 4.84 F10.0 m span bridge 82.40 E 4.84 FLow-level crossingsSimilarly Form T12 does not specifically recommend low-level crossings. This is because theyare only suitable in special circumstances. They have frequently been used in unsuitablelocations in Cambodia and without a rational consideration of design criteria or the benefits.Some brief guidance on the correct use of low-level crossings is given below.Template designs are provided for two types of low-level crossing: x A Drift crosses a watercourse at bed level; whenever there is flow or standing water in the watercourse there will be water on the drift roadway. x A Vented Causeway has culverts beneath the low-level crossing roadway such that the roadway is higher than the stream bed but usually lower than the approach roads. This allows the roadway to remain dry when there is a normal flow or standing water in the watercourse but also for the roadway to be submerged for short periods during a flood.Drifts are suitable for hilly areas where there is no flow or a trickle of water for most of the timebut where the stream flows full for a short time following heavy rainfall. Drifts are not suitablefor crossing areas where flood water may stand several weeks or months a year, as occurs inmany locations in lowland Cambodia.Vented causeways can be used in lowland areas provided the roadway is above standing floodlevel. They can provide extra capacity to pass large flood flows. However providing sufficientlength of causeway and protection against damage can make a vented causeway moreexpensive than box culverts or a small bridge. The criteria that should be used are as follows. x The vent culverts can be assumed to have the capacity listed in Table 5.8. x The safe depth of flowing water on the roadway is 150 mm. If the water is deeper than this cars and light 4-wheel drive vehicles can float, this has been the cause of many deaths by drowning worldwide. x At this flow depth the flow per metre length of causeway is 0.18 m3/s. Therefore a 91 m long roadway and protected slopes is required to provide the same capacity as a single 3.0 mW x 2.0 mH box culvert. It is obvious that in most locations the box culvert is a better solution. Think very carefully about your reasons for choosing a drift or vented causeway, a conventional culvert will often be a better technical and cheaper solution.Study and Design Guidelines I-130
    • Part 5: Study and Design Guidelines Drifts and vented causeways can be used as spillways for small irrigation reservoirs, provided proper consideration is given to erosion protection downstream, seek specialist advice.5.3 Irrigation System: Group 102The design guidance for an Irrigation system is presented in three parts. x Form T21 gathers general information about the irrigation system, estimates the irrigation water requirements and lists the canals and structures that may be needed. x Form T22 is used for the design of earthworks which includes canals and drains, dams and dykes. x Form T23 is used for all irrigation structures including headworks and distribution system structures.5.3.1 Irrigation Project: Form T21It is unusual for a completely new irrigation system to be built under the C/S Fund; such projectsare usually built by MOWRAM/PDOWRAM under donor support. It is more usual for theC/S Fund to repair or improve part of an existing irrigation system. Often these are systemsbuilt by the Khmer Rouge Regime which have fallen into disrepair because they were badlyconceived, designed and constructed. Sometimes a system will have been rehabilitated bydonors who often only provide headworks but leave the community to complete the distributioncanals – which is seldom done because communities lack the knowledge and resources to dothis on their own. Occasionally systems date from the Sihanouk or French eras.Although a lot of money has been spent on irrigation infrastructure in recent times, includingsupport through the C/S Fund, the works have tended to be piecemeal because noconsideration has been given to the overall operation of the system or how it interacts withadjoining land. The issues are very complex and beyond the scope of this design guidance.However the completion of Form T21 is intended to draw attention to key issues to helpC/S Fund investment in irrigation to be more effective and also alert when more specialistadvice is needed.Irrigation infrastructure in Cambodia is most often used for supplementary irrigation of wetseason rice. This is especially so for those systems which rely on rainfall upon a catchment. Itis unlikely that such systems can support irrigation of more than 10% of the area for part or all ofthe dry season. A longer irrigation season is possible in areas benefiting from the annualMekong, Tonle Sap and Bassac flood. In these places it is common to find deep water andrecession cropping, the so called ‘Preks’ or ‘Colmatage’ systems, or land where water ispumped from seasonal flood lakes. Form T21 links with an applet that estimates the irrigation water requirement for rice on a monthly basis. It assesses the water resource and whether it is sufficient for a river fed system or if a reservoir is needed, the required volume of the reservoir. The water resource assessment also gives consideration to competing irrigation water demands upstream and downstream of the project.The design guidance incorporated into Form T21 is loosely based on the ICID Checklist16 forrapid feasibility study of irrigation systems.Irrigation system requirementThere are a series of questions on Form T21 which establish the areas of land that requirewater in the wet and dry season and the crops that will be grown. These questions must be16 International Commission for Irrigation and Drainage. Checklist to Assist Preparation of Small- Scale Irrigation Projects in Sub-Saharan Africa, via Department for International Development, London, England, 1998.Study and Design Guidelines I-131
    • Part 5: Study and Design Guidelinesanswered because the information is used to calculate irrigation water requirements later in theform.There are also questions about water shortage.FloodingThe questions on floods have two purposes: x Find out if the fields are flooded for part of the year, if this is the case then the system should manage the water levels for the maximum benefit to the cropping. x Find out if flooding is a significant constraint to cropping, either because it will damage a standing crop or it will dictate the time a crop is planted.Existing irrigation systemThe questions about the existing irrigation system are to establish the age of the system, itscurrent condition and what are perceived as the main problems – very importantly which monthsof the year water is available.Water resourceThere is a simple series of questions that establish where the water comes from and when it isavailable. The questions about water depth and flow should be answered with the help of thecommunity. The key issue is to find out which months there is flow in the system. E.g. there is no point in building a dam to irrigate in June when the water in the stream that will fill the reservoir never flows until August!There is an important question to establish whether water can flow to the fields by gravity orwhether it must be pumped.There are also questions to establish the competition for water, about the approximate area ofirrigable land upstream and downstream of the project. Promoters of irrigation systems inCambodia seldom consider this issue but it is very important. Even if there is little workingirrigation now, maybe in the future the villages upstream will also have a scheme. Unless thewater resource is large enough for both projects the water previously available for the C/S Fundproject will be reduced and it may no longer be viable.Rainfall recordRainfall records are available for Provincial Capitals, and since about 2001 most District Towns.Sometimes the records are incomplete but will be good enough for this purpose.Rainfall records only need to be collected once. The records for the whole province should beobtained and updated annually. Work through the PDOWRAM to obtain the records.Form T21 allows for a rainfall record at or near the project and a second record for thecatchment. In most cases only one record will be available, probably for neither of theselocations but for the nearest District or Provincial town. It is OK to use this record but if morelocal records are available use these instead.Fill both rainfall columns into Applet T21 because the numbers entered are used to calculate theirrigation water requirement and assess the water resource.Irrigation water requirementThe irrigation water requirement is needed to check the demand for water against availablewater – this is known as a ‘water balance’. Form T21 uses applet T21 that calculates the irrigation water requirement for rice on a monthly basis. After the calculation, upload the Applet to the geneator.Study and Design Guidelines I-132
    • Part 5: Study and Design GuidelinesIt is necessary to enter the catchment area. The applet then uses the irrigated area and therainfall data previously entered. It is also necessary to enter the planting date for rice. Theapplet then outputs the water requirement each month as the total quantity of water in m3, asthe flow rate in m3/s if water is pumped 8 hours each day, and as the flow rate in m3/s if water isdelivered over 24 hours by gravity. An approximate water balance is also made to estimate thestorage volume required of a reservoir.Dependable rainfallThe rainfall records are converted to ‘dependable rain’. Dependable rain is the monthly rainfallhaving an 80% probability of exceedance17 (i.e. that is likely to occur in the particular monthunder consideration in four years out of five). The dependable rainfall is calculated with thefollowing formula: Pdep = 0.6Ptot - 10 (for Ptot < 70 mm/month) Pdep = 0.8Ptot - 24 (for Ptot > 70 mm/month)where Pdep and Ptot are respectively monthly mean dependable rainfall and monthly meanmeasured rainfall in millimetres. Once you have entered the monthly rainfall record, the applet calculates dependable rainfall on a monthly basis.Crop water requirementIt is time consuming to estimate the variation in crop water requirements throughout thecropping season (requiring estimates of evapotranspiration, use of crop factors, etc). For ricemonoculture the variation project to project is small and for small rice irrigation projects inCambodia it is accurate enough to assume approximate typical but safe estimates of monthlycrop water requirements. On this basis, it is sufficient to know only the total area under irrigatedcrops each month. For paddy rice, all months from the start of nursery and land preparation toharvest should be included. The following has been assumed for design guidance: First month: Nursery requirement 100 mm Second month Land preparation and planting 400 mm Third month Growing 300 mm Fourth month Growing 300 mm Fifth month Growing 200 mm Sixth month Harvest 50 mmFor recession rice the nursery, land preparation and planting requirements can be omitted onthe assumption that these activities are carried out on flooded land.Planting monthThe planting month can be varied. You should try different planting months to see how thisaffects water requirements and reservoir volume. It is probable that farmers will have to changetheir usual planting date to get the maximum benefit from irrigation. These issues should bediscussed with the Commune (or FWUC if one exists or will be established).Irrigation water requirementThe net irrigation requirement is calculated by deducting the dependable rainfall from the cropwater requirement.The overall efficiency of distribution, from water source to the soil in which the plant is growing,is typically 40% for surface (channel) irrigated schemes. Therefore the actual irrigationrequirement is calculated as: Net irrigation requirement ÷ 0.417 FAO Irrigation and Drainage Papers No 25 "Effective Rainfall" and No 46 "CROPWAT: A Computer Program for Irrigation Planning and Management"Study and Design Guidelines I-133
    • Part 5: Study and Design Guidelines The applet calculates the net irrigation water requirement for the chosen month of planting taking into account the contribution from dependable rainfall.Work proposed for irrigation projectForm T21 is finished by filling the requirement for earthworks and structures, stating whetherthese are new or repairs, and the expected sizes. This generates Forms T22 and T23 for eachseparate output required.5.3.2 Irrigation Earthwork: Form T22Irrigation earthworks Form T22 is used for design of canals and drains, dams and dykes. Theremust be one form for each earthwork, e.g. there must be one form for one dam, and twoadditional forms if there are two canals. This is because the design guidance can only bespecific to one earthwork at a time, and in the case of more than one canal or drain the flow ineach will be different each time. Form T22 will design dam and dyke cross-sections including any road surface, it also calculates flow in a canal or drain calling-up an applet T22 to calculate drainage flow from an external catchment. A second applet T22 is called-up for the hydraulic design of canal and drain cross-sections.Traffic use of earthworkThese questions are included because irrigation earthworks are often used as roads, not justfarm roads but tertiary and sub tertiary roads. The questions focus on the condition of existingearthworks used as road and the traffic that will use the earthwork when it is completed. Theguidance is similar to Form T11 except that a traffic count is not required and instead the trafficis estimated. The heaviest vehicle using the road is also considered. If the road on the earthwork already carries a lot of traffic it is worthwhile to make a traffic count even though Form T22 does not specifically require it.Condition of existing earthworksThese questions are asked to establish why the earthworks need repair. If there is a clearcause of damage then the design must protect against the same damage in the future. Don’t repair damaged infrastructure until you establish why the damage occurred. If you do so then the same damage may occur again. Ask local people how the damage occurred but do not assume that their answers are correct, think whether the cause is for more complex reasons than they say.SoilsThe soils at the site determine the safe slopes for canals and drains, dams and dykes. Theform provides advice on safe slopes according to the soil type identified; in the case of a canalor drain if the soil is poor Form T22 can advise channel lining.Fill materialThese questions establish whether suitable fill material is available. If it is not then specialistadvice may be needed in order to proceed with the design.Design of dam or dyke It is necessary to answer a series of question on Form T22 to complete the design. The questions are listed below together with explanation of the reason for the questions and advice on how to answer.What is reservoir full supply level at dam or flood levels at dyke (m)?Give the level using the project datum. This information is needed to work out theStudy and Design Guidelines I-134
    • Part 5: Study and Design Guidelines height of the dam or dyke.What freeboard will be allowed (m)?Freeboard is extra height above the water Freeboard should not be less than 1.0 m,level to provide a margin of safety, allow add more if waves are expected to be afor some settlement and erosion, and for problem (0.5 m can be assumed for smallwaves that may be caused by a wind. reservoirs). Do not include the depth of road surfacing when deciding freeboard; this must be added in addition to freeboard.Will the dam or dyke be used as a road? This influences the crest width and the surface protection.What is the crest width? Minimum for a farm road is 2.0 m but 4.0 m is better. If it is a tertiary road use the guidance for Transport Infrastructure.Will the crest be surfaced?What thickness of Laterite (mm)? Follow the advice on surfacing depending on the expected traffic use.What will be the upstream slope (see advice for soils above)?What will be the downstream slope (see advice for soils above)? The advice provided in response to the soil questions should be followed. Under no circumstances should steeper slopes be used.What slope protect will be provided to the upstream slope?Select from the options. As a minimum it is advised to use grass slope protection. For a reservoir or a flood dyke where there is open water more than 1.0 m deep and extending more than 500 m distance each year, it is best to use riprap.If ‘rock riprap’ is chosen the following questions appear.What class of riprap?Answer Class A, B, C or D Class A rip rap is suitable for small reservoirs.What thickness of riprap in millimetres? 300 mm is the minimum thickness for Class A riprap.What filter will be placed below riprap?There must always be a filter below riprap Use either a 150 mm gravel layer or a 50 mm sand layer over a geotextile filter fabric.What slope protection will be provided to the downstream slope? It is advisable to provide grass.Capacity of canalCanals should be designed to supply not less than 2 litres/second/hectare to the fields supplied.This assumes water is supplied continuously over 24 hours; if the water is pumped then thecanal must be larger, e.g. if it is only pumped 6 hours each day the rate must be: 2 x 24 ÷ 6 = 8 l/s/hIt does not matter whether the farmers take the water in turn or all at the same time, 2 l/s/h willmeet the peak requirements for paddy rice.Study and Design Guidelines I-135
    • Part 5: Study and Design Guidelines The required capacity of the canal depending on the answers given to the questions on Form T22. It is the factor between area supplied and supply rate.You must enter the area supplied by the canal. The default supply rate advised by the form forcalculation is 2 l/s/h but you can enter another flow rate. You answer whether the supply is bygravity or pumping. When it is by pumping you must decide how long the pumps will run eachday. Then you need to calculate the capacity of the canal for the selected method of deliveryand fill into the form as advised in the Project Generator itself.Capacity of drainOnly rarely will purpose built irrigation drains be provided under the C/S fund. However, it iscommon for rehabilitated canals to function as both a canal and drain, particularly Khmer Rougebuilt systems. The capacity required for a drain is greater than that for a canal. Therefore,wherever a canal may operate as a drain it is important to check the design as a drain.When no drain is provided the form requires explanation of how the irrigation system is drained,e.g. water may drain into a river. Form T22 requires the calculation of required capacity including taking into account an external catchment also served by the drain which needs to be calculated by using Applet T22 Extenal Catchment Flow.Drains should be designed to convey not less than 3.5 l/s/h from the fields drained. The defaultdrainage rate used by the form for calculation is 3.5 l/s/h but the form allows you to chooseanother flow rate.Often a drain will also collect runoff from other fields or have a catchment upstream. When thisis the case you must answer so on the form and enter the catchment area. If this area is”1.0 km2 then it assumes these are fields and you need to calculate the extra flow based on3.5 l/s/h (or whatever other value you have entered on the form). If it is larger than 1.0 km2 theform needs the additional flow result form applet T22 External Catchment Flow. The Applet T22applies the GTFM as described for Applet T12, except that it designs for the mean annual flood(about 5 year return period) and only outputs the flow.Hydraulic design of canal or drainOnce you know the flow in the canal or drain you must calculate the channel size. This is thehydraulic design. Form T22 uses applet T22-Design of canal or drain to calculate the channel size for the flow calculated as described above. All you need to do is select a few design criteria and the Applet includes advice on how to choose these.Manning’s formulaThe simplest way to design a channel is to use Manning’s formula but first it is necessary tounderstand the Continuity Equation.The continuity equation describes the fact that flow rate can be calculated by multiplying thecross sectional area of flow by velocity of flow, it is written: Q A uV 3 Where: Q = flow rate (discharge) (m /s) A= cross-sectional area of the flow (m2) V= velocity (m/s)Study and Design Guidelines I-136
    • Part 5: Study and Design GuidelinesOnce the size of flow has been decided, the size of the canal can be calculated using Manning’sformula. Manning’s formula calculates flow velocity. In some books use of Manning’s Formulais referred to as the Slope Area Method. 2/3 1 § A· V ¨ ¸ s1 / 2 n©P¹ Where: V : velocity (m/s) A: cross-sectional area of the flow (m2) P: length of wetted bed at the cross-section (m) s: gradient of water surface or bed slope n: Manning’s n representing the channel roughness, see Table 5.9.Table 5.9 – Manning’s n Channel surface Manning’s n Earth (Primary and Secondary canals) 0.025 Earth (Tertiary and Quaternary canals) 0.030 Earth (Drain) 0.035 Concrete (and plastered masonry) 0.015 Masonry 0.020 Gabions 0.025Manning’s formula is also used to calculate flow, simply by using the continuityequation Q A u V , which means we only have to multiply the velocity V calculated byManning’s formula by the flow cross-sectional area. 2/3 A§ A· V ¨ ¸ s1 / 2 n ©P¹ Where: Q : flow volume (m3/s) A: Cross-sectional area of the flow (m2) P: Length of wetted bed at the cross-section (m) s: gradient of water surface or bed slope n: Manning’s ‘n’ representing the channel roughness AThe expression in Manning’s formula is sometimes written as R which is called the Phydraulic radius or hydraulic mean depth. A R PDesign calculationHand calculation for channel design using Manning’s formula is a ‘trial and error’ processbecause you first must select the channel dimensions, make the calculation and compare thatwith the required capacity. Therefore designers tend to use charts or spreadsheets to quicklycomplete the design. Form T22 calls-up Applet T22-Design canal or drain which will do thecalculation.Study and Design Guidelines I-137
    • Part 5: Study and Design Guidelines It is necessary to answer a series of question on Applet T22 to complete the design. The questions are listed below together with explanation of the reason for the questions and advice on how to answer.What will be the bed level at the upstream end (m elevation)?What will be the bed level at the downstream end (m elevation)?What is the distance in metres along the centreline between the upstream anddownstream ends of the channel?These questions must be answered to Strictly it is the water surface (hydraulic)calculate the gradient s. Hence channel gradient that controls flow but for simplegradient is (upstream level – downstream channel design it is good enough to use thelevel) ÷ distance bed gradient. Even more helpful is that the canals and drains must follow the slope of the ground so if you know the ground slope you can fill in answers that will give this slope as the gradient, although you can then change it to get the optimum design.What is the bank slope V:H?This is used to calculate the cross- Follow the advice on slopessectional flow area and the length of V given at the soils box ofwetted bed. Form T22, rectangular lined H channels will be 1:0.What is the bed width (m)?This is used to calculate the cross-sectionalflow area and the length of wetted bed. Bed widthWhat is the freeboard (m)?Freeboard is the difference in height Form T22 gives the following advice basedbetween the top of the bank and the water on general practice on MOWRAM projects:surface. It is provided as a margin of Secondary canals: 0.5 msafety so that the design flow is contained Tertiary canals: 0.2 mwithin the channel. Drains ” 2 m3/s: 0.1 m Drains 2 to 8 m3/s: 0.2 m Freeboard Drains >8 m3/s: 0.3 mWhat is ‘Manning’s n’ (channel roughness)? Form T22 gives the following advice: Earth secondary canal: 0.025 Earth tertiary canal: 0.030 Earth drain: 0.035 Concrete lined: 0.015 Masonry lined: 0.020What is the design flow?This will be taken from form T22 unless youchose to enter another flow.You will finally get the results as the followings: x Water depth (m): x Bed depth below ground level (m) (at upstream and downstream surveyed locations): x Width between tops of bank (m) (at upstream and downstream surveyed locations): x Velocity of design flow (m/s)Study and Design Guidelines I-138
    • Part 5: Study and Design Guidelines5.3.3 Irrigation structure: Form T23Irrigation structures Form T23 is used for all irrigation structures. There must be one form foreach structure, e.g. there must be one form for one spillway, and one form for one headregulator, and two forms for two culverts. This is because the design guidance can only bespecific to one structure at a time, and for different structures the flow requirements will bedifferent each time.The form requires that you select the type of structure; it will be noted in form itself whetherwhat questions to answer and what should not according to the chosen structure. For smallirrigation flow control structures, output can be selected according to the Table 5.10 below.Material available for constructionThese questions indicate whether there will be problems complying with the Specification, e.g. ifgravel will come from a river then it will be rounded and unsuitable for concrete.Soils and Dynamic Cone Penetration Test (DCP)Information on soils and DCP tests is needed to consider whether the foundations will be strongenough to support the structure, also whether they will be particularly vulnerable to erosion andscour.The DCP results are used in the same way as described for road projects. One test may besufficient for a small culvert but for a spillway or structure of large extent it is recommended tocheck each bank and the water channel, as many times as necessary.Road crossingIrrigation structures are often used as road crossings. The template designs a suitable forTertiary Roads. These questions are included as a check whether special provisions arenecessary.Hydraulic capacityThese questions apply for irrigation flow control structures. Since these will be on canals ordrains you should already know the capacity needed from the T22.Indicative capacities for template designs are given in Table 5.10. These are not absolutebecause the flow depends on the relative upstream and downstream water levels.There are questions asking if the flow at the structure can be larger than the design flow and ifso what provision can be made to safely pass the additional flow. This is important because forexample although you may have designed a canal for a certain flow farmers might leave a gateopen too wide upstream and extra flow may come down the canal, on drains a larger flow thandesigned for will likely occur every few years. Make sure that the design will survive this type ofoccurrence.Table 5.10 – Indicative hydraulic capacity of template small irrigation flow structures Capacity Code Description m3/s1020201 Medium size water gate (2.0 mW) 5.51020202 Single pipe culvert 0.6 m diameter with gate 0.51020203 Single pipe culvert 0.8 m diameter with gate 1.01020204 Single pipe culvert 1.0 m diameter with gate 1.81020211 Double pipe culvert 0.6 m diameter with gate 1.01020212 Double pipe culvert 0.8 m diameter with gate 2.01020213 Double pipe culvert 1.0 m diameter with gate 3.61020221 Triple pipe culvert 1.0 m diameter with gate 5.4xxxxxxx Single cell box culvert with gate (2.0 mW x 1.0 mH) 5.5xxxxxxx Double cell box culvert with gate (2No 2.0 mW x 1.0 mH) 11.01020251 Pipe head regulator 0.3 m diameter 0.11020251 Pipe head regulator 0.6 m diameter 0.5Study and Design Guidelines I-139
    • Part 5: Study and Design Guidelines1020251 Pipe head regulator 0.8 m diameter 1.01020251 Pipe head regulator 1.0 m diameter 1.81020252 Check structure VariesSpillways and diversion weirsA dam spillway, or a weir across a river that raises water levels to divert flow for irrigation mustbe designed to pass flood flow without suffering damage. It is common for spillways onreservoirs in lowland areas to flow up to two months a year because the reservoirs are too smallto capture all the wet season flow. Weirs across rivers will spill water for even longer, in somelocations all through the year.The design should be for a large flood. International practice is to design for very large floodsbecause of the risk of loss of life and damage should a dam fail because of too small a spillway.These standards are not applied to small irrigation reservoirs in Cambodia; in flat areas thereasons can include the relatively small storage volume and that water escaping is not confinedin a valley but can quickly spread over the fields. These are not universally safe assumptionsand would not be appropriate for a reservoir in a hill valley with a village or scattered housesdownstream.The guidance applies for small lowland reservoirs in flat areas. In these cases spillways andriver weirs can be designed for a 1 in 50 year peak flow. In the case of a reservoir the flow willactually be lower than this because some of the flood will be delayed a short time passingthrough the reservoir but for simplicity this has been ignored. Form T23 uses an applet to estimate the peak flow and to calculate the length of weir required to pass the design flood.When a spillway or weir is proposed Form T23 will call-up Applet T23 Length of weir whichestimates the peak flow and calculate the length of weir. Flow is estimated using the GTFM asdescribed for Form T12, except that it designs for the 1 in 50 year flood and only outputs theflow.The Applet will ask for the maximum acceptable water level upstream of the spillway or weir andthe proposed crest level. The maximum acceptable water level should take into accountproperty that could be flooded or the freeboard allowed at a dam. The crest level will be the fullsupply level for a reservoir or the level needed for water to flow to a diversion canal. Thedifference between the two water levels is the head available at the weir. The applet works outhow much water will flow over a metre length of weir at this head. It then divides this into the 1in 50 year peak flow to calculate the length of weir needed. The weir must be capable of passing the full flood flow. Never include flow that could bypass the weir by opening a water gate or head regulator because when the flood comes there may be no one there to open the gate. This was a frequent problem with Khmer Rouge schemes which relied on someone opening the gates to pass the flood flow – it is amongst the many reasons why so many of these structures have failed.Pumping capacityIf the selected output is a pump then the pump capacity must be entered. This may have beencalculated on a Form T22 if a canal is included in the project.5.4 Water Supply: Group 103Simple design guidance is provided for Water Supply. Four types of water supply infrastructureare addressed: x Wells x PondsStudy and Design Guidelines I-140
    • Part 5: Study and Design Guidelines x Rainwater storage x Piped water systemsThe guidance does not include: x Calculation of water supply volume based on per-capita consumption. x Pipe sizing and hydraulic design for piped and pumped water supply systems.Form T31 is used. The form is designed for a water supply project, but there must be one formfor each output. If a project comprises several outputs such as pumped wells, water tanks anda pipe distribution system, it is required one Form T31 for the pumped wells, another for thewater tanks, and the other one for the pipe water system. It is because one form can onlyprovide one set of associated templates drawings and quantity table.Quantity of proposed outputsThe proposed outputs you have chosen need to be quantified in number or size beforeproceeding to complete the form.Purpose of water supplyThese questions establish whether the water supply is for a community (domestic), a school,health or other facility. School and health projects often include water supply and if the projectsinclude the water supply, the Project Generator will require a Form T31 to be completed.Information about the number of usersThis indicates the number of people who will benefit. It is also an indication of the potentialdemand on the water supply.The questions establish the population of the village(s) and the number of households in thevillages benefiting from the water supply. It also asks how many households will use the watersupply. For schools it asks the number of pupils.Water demandForm T31 does not calculate the water demand but you should still consider this. The WorldHealth Organization recommends 30 l/head/day for domestic use. Consumption is alsoinfluenced by the distance from a well or water point if water has to be carried.Table 5.11 - Water consumption and distance to water source (well or water point) Distance to source Estimated consumption (litres per person per day) More than 1000 m 7 500 to 1000 m 12 Less than 250 m 20 to 30 In the compound of the dwelling 40You can use these figures to make a side calculation to check whether the proposed projectcan supply enough water. Remember that children at school or visitors to a communityfacility such as a health post get only part of their daily requirement there. However, it isquite common for a well in a school grounds to be used by nearby residents so you mustconsider if the project can satisfy such an additional demand.Existing water supplyThese questions are designed to establish the existing sources of water supply by type, numberof users and where relevant distance from the household to the source.Study and Design Guidelines I-141
    • Part 5: Study and Design Guidelines Will the new water supply replace the water supply or will it be additional to the original supply? Will the existing and new systems compete for the same water?Information about site of proposed facilityThese questions establish ownership of the land, if the land is not in public ownership there maybe disputes about access in the future.Political considerations may influence accessibility. There may be pressure to put the well nearthe dwelling of an influential member of the community. A compromise may be necessary.There are also questions about flooding. There is a risk of contamination of the supply if theland floods; a well provides a path for pollution to reach the groundwater which can bepermanently contaminated making it unusable for water supply. It may be necessary toconstruct the water supply, e.g. a well head, on a mound or platform so that it is accessible andprotected against contamination when there is a flood.Existing wellsInformation on existing wells is very Useful Definitionsuseful for designing a new well. The Aquifer A water-saturated geologic zone thatprimary objective when sinking a will yield water to springs and wells.new well is to sink it where groundwater is likely to be found. Existing Bacteria One-celled microorganisms whichwells are the best indication of the multiply by simple division and whichpresence of ground water. The can be seen through a microscope.history of the old well will provide Contaminate To make unclean by introducing aninformation on seasonal changes in infectious (disease-causing) impuritythe water tab1e, which may indicate such as bacteria.that the new well should be deeperthan the old one. The questions ask Drawdown The distance between the water tableabout the type of well and its use, and the water level in a well duringthe depth of water particularly during continued pumping.the dry season, the soil and rock Ground Water Water stored below the ground’sthat the well is sunk in. The surface.questions about the colour, tasteand smell of the water are good Impermeable Not allowing liquid to pass through.indicators of the water quality18. Permeability The ability of soil to absorb liquid.Form T31 is designed to collect Porosity A soil’s ability to store water.information about every nearby well.However, if there are many existing Water Table The top or upper limit, of an aquifer.wells, household hand pumps orfarm tube wells, then it is only necessary to get a representative sample of wells, say a fewwells for one project depending on how much they vary. The location of all existing wells shouldbe plotted using MangoMap.Proposed wellsGroundwater is water that is stored underground in porous layers called aquifers and can be areliable source of drinking water. Naturally occurring sources of groundwater are usually freefrom disease causing bacteria. There is usually less seasonal variation in groundwaterquantities than in surface water.Wells are used to extract groundwater. A well is simply a hole that pierces an aquifer so thatwater may be pumped or lifted out. Wells can be classified according to their method ofconstruction. Five types of wells are: hand-dug, driven, jetted, bored, and cable tool.18 These questions are the same as used on the RGC National Water Well Log Sheet.Study and Design Guidelines I-142
    • Part 5: Study and Design GuidelinesSelecting a well siteSelecting a well site properly is important to ensure that the well will tap into a reliable source ofgood quality ground water, and to ensure that the water will not be contaminated in the future.Selecting a site involves considering existing wells, local geography, quality and quantity ofgroundwater, possible sources of contamination, accessibility to users, and proposed methodsof well construction.Where possible, sink a new well near an old one and groundwater will probably be reached atabout the same depth. However, if the new well is to be used in addition to the old one, caremust be taken not to sink it too close to the existing well. Otherwise, the yield of one or bothwells may be adversely affected. This is due to the effect that a well has on the surroundingwater table.DrawdownWhen water is pumped or lifted Figure 5.7 – Well components and drawdownout of a well, the water level inthe well falls below the original Ground levellevel, called the initial or staticwater level, until it stabilises ata new level, called the pumpedlevel. The distance between Initial or static water levelthe static level and thepumped level is the drawdown. DrawdownThe water table surrounding awells curves down to the Cone of depressionpumped level, forming a cone (Pumped level)of depression as shown byFigure 5.7. If the cones of Well casingdepression of two wells Aquiferoverlap, the pumped level inone or both wells will be Well Screenlowered and the yield will bedecreased.Local Geography Impermeable layerIf no wells exist, the presenceof ground water can beindicated by surface water, topography, and certain types of vegetation. Surface water. A successful well can generally be sunk near a river because the river will replenish the ground water and reduce changes in the water tab1e. Water taken from such a well is usually cleaner and cooler than water taken from the river. If the well is deep, water may be available even when there is no water in the river during the dry season. Topography. Ground water gathers in low areas. Therefore, the lowest ground is generally the best place to sink a well. In hi1ly areas, valley bottoms are the best places for wells. An exception to this could be where there is a spring on the side of a hill. The spring may indicate lateral movement of ground water over a layer of impermeable soil. If so a successful well could be sunk uphill from the spring. Use MangoMap to draw all rivers, springs, and topographical features (that are not already shown on the base mapping). Vegetation. Certain types of vegetation can indicate that ground water lies near the surface. The most useful indicators of ground water are perennial plants (those present year round), especially trees and shrubs. Annual plants, such as grasses, are not goodStudy and Design Guidelines I-143
    • Part 5: Study and Design Guidelines indicators, because they come and go with the seasons. The dry season is probably the best time to survey vegetation for indications of ground water.Quality of Ground WaterOnce ground water is located, its quality must be checked before constructing permanent wells.Of course, the best way to establish water quality is chemical and biological water quality tests,but you have to consider whether the extra time and cost is justified. As a minimum the watermust be clean, clear, and good-tasting, and be free from disease causing organisms. If theground water is contaminated, another source may have to be found. If physical, chemical andbacteriological water testing is possible then indicative standards are given in the Water Qualitysection which follows below.Quantity of Ground WaterThe quantity of a groundwater source is nearly as important as its quality. Unfortunately, theonly way to test the yield of an aquifer is to sink a we1l and pump it. You can, however, make arough estimate of the yield by identifying the sediment and rock which compose the aquifer.The two most significant elements of an aquifer are its porosity and permeability. Porositygoverns the amount of water that an aquifer can contain. Permeability governs the amount ofwater that can be brought to the surface. For example, some aquifers may contain largequantities of water, but their rate of yield is too slow to suit the needs of the user. Porosity andpermeability depend on a number of factors including particle size, arrangement anddistribution.Table 5.12 shows the estimated yields of aquifers composed of different types of sediment. Thetable should not be used for exact calculations but only for indications of yield.Table 5.12 - Estimated yields of aquifersAquifer Estimated Yield (litres per minute)Sand and gravel 11,000; could be less based on pump and well designSand, gravel, and clay 1,900-3,800Sand and clay 1,900Fractured sandstone 1,900Limestone 38-190; more if near stream, or if there are underground cavernsGranite or hard rock 38 or lessAs a general guide during the dry season drilled wells should be able to sustain yields of at least1,000 l/h for 8 h/day. For dug wells for a standing water depth at least 3 m should have aminimum yield of 10 l/minute, or 2.5 m of water and 15 l/minute, or 2.0 m of water and20 l/minute.If the quantity of ground water is insufficient, another or additional well sites or even alternativesources will have to be found.Possible Sources of ContaminationA well should not be dug in areas where the ground water is likely to be contaminated. A wellsite should be uphill and at least the safe distances listed in Table 5.13.Table 5.13 – Safe distance of well from sources of contamination Safe distance Source of contamination 50 m Seepage pit or cesspool; 30 m Sub-surface absorption system; 30 m Pit latrine; 30 m Animal pens, sheds, or silos; 15 m Septic tank; 7m Drain, ditch, or house foundation. 50 m Petro-chemical or agri-chemical store;Study and Design Guidelines I-144
    • Part 5: Study and Design GuidelinesFloodingThe well site should not be subject to flooding during the wet season or any other time. This willbe of greatest concern where the well is in a low area or near a river that yearly overflows itsbanks. The site can be protected from flooding by raising the well head above maximum floodlevels; building small dams or ditches to prevent flooding is an unreliable solution. If the wellcannot be protected against flooding, another site should be considered.Record all possible sources of contamination using MangoMap.Accessibility to UsersThe well site should be as close as possible to the users. As the distance between the well andthe user increases, the per capita water consumption decreases. The typical effect is shown inTable 5.11.Methods of Well ConstructionThe proposed method of well construction must be suitable to the soil conditions at the well site.If not, another site must be found or another method of construction must be considered. Table5.14 shows some of the limitations of well construction methods based on soil conditions.Table 5.14 - Well construction methods and soil conditionsConstruction method Unsuitable SoilHand Dug Hard rock, large bouldersDriven Hard rock, heavy clay, boulders, coarse gravelJetted Hard rock, bouldersBored Hard rock, boulders larger than augerCable Tool NoneDrainage of well siteIt is important to provide drainage for water spilt at the well head. If this is not done there will bemuddy puddles; these have potential to pollute the well and are a breading place formosquitoes. The template designs show a soakaway but if there is a suitable pond or ditch thiscan also be used.Suitable pump for wellThe type of hand pump depends on the dynamic water level (static water level plus drawdown).MRD established hand pump standardization in 1994 for different levels of lift capacity:Standard Pump type VN No 6 Tara AfridevLift capacity 7 13 30(preferred) in m.Max. Discharge in 1,200 1,000 1,000liters/hourCost price (appr.) in 35 250 500US$Regular spares for 1 cup seal, flap valve, cup seal, 2 flap U seal, 2 bobbins, O-year operation pivot axles valves, O-ring ring, 4 bearingsThese days standardization is not followed anymore and mostly the VN No6 hand pump is usedfor low lifts and the Afridev for medium lifts. The locally manufactured Rovai Pump (also calledthe Rope Pump) is used for all lifts in both hand dug wells and drilled wells.Study and Design Guidelines I-145
    • Part 5: Study and Design GuidelinesMore advice on pump selection can be found in: “UNICEF – A Water Handbook19.”For medium lift 30 to 50 m. UNICEF include Afridev amongst recommended pumps butgenerally in Cambodia they are not used at this depth. Such deep wells are not usuallyprovided under the C/S Fund but if one is required it is advisable to seek specialist advice.PondsThe questions for ponds are similar in concept to wells except that the pond will usually beshallower and will cover a large area. Information on the soils will decide the suitability of theground as well as the stable side slopes. The questions ask where the water to fill the pond willcome from and whether there are potential sources of contamination nearby.Table 5.15 – Recommend maximum slopes for dug water supply pondsSoils type Maximum stable slope (V:H)Clay group 1 : 1.25Sandy group 1 : 1.5Silty soils 1 : 1.5Dispersive clays20 May require additional slope protection.A pond in sandy soil will probably filled by shallow groundwater flow during the wet season butwater will quickly drain away once the groundwater levels drop in the dry season. A pond in aclay soil will retain water much better but groundwater inflow will be small and to fill it will haveto rely on direct rainfall or captured runoff from surrounding land. You should consider thepossibility of low bunds and channels in situations where this will increase the capture of runoff.Water qualityThe Royal Government of Cambodia has established a comprehensive policy on NationalWater Supply and Sanitation, covering both urban and rural water supplies. Based on this policyand to ensure access to safe drinking water to all people, it required the Drinking Water QualityStandard (DWS) for Cambodia21. These standards were developed by an inter-ministerialprocess initiated by Ministry of Industry, Mines and Energy and concerned ministries withsupport from the World Health Organization in 2004.Drinking water should be clean and clear with pleasant taste and odor. The public will assessdrinking water quality using these aesthetic indicators but actually the safety of water isdetermined by microbiological, physical, and chemical quality. It should be safe so that it doesnot contain suspended matter, harmful chemical substances, and disease-causingmicroorganisms. Microbiological quality is most important and is a priority for monitoring.TablesThe associated templates drawings and quantity table can then be called up by the ProjectGenerator. For some outputs there may be no Template design. In these cases a design andquantities will have to be provided.All water supply systems should be tested for water quality parameters set out in Tables 1through 4 prior to commissioning to ensure compliance with DWS. Small water supply systems(those serving less than 100 people or delivering less than 10 m3/day) should be tested forpriority parameters set out in Table 5.20 Priority parameters in small water suppliesTable 5.16 Bacteriological quality for drinking waterParameter Maximum Value a) Thermotolerant (Fecal) Coliforms 0 per 100 mL or E. coli b) Total coliforms 0 per 100 mL19 UNICEF. Towards Better Programming - A Water Handbook, Water, Environment and Sanitation Technical Guidelines Series - No. 2, United Nations Children’s Fund, 1999.20 Clays which dissolve in contact with water.21 MRD, Drinking Water Quality Standards for Cambodia, January 2004Study and Design Guidelines I-146
    • Part 5: Study and Design GuidelinesTable 5.17 Inorganic constituents of health significance in drinking waterParameter Maximum Value* mg/L, (ppm)Arsenic 0.05Barium 0.7Cadmium 0.003Chromium 0.05Cyanide 0.07Fluoride 1.5Lead 0.01Mercury 0.001Nickel 0.02Nitrate as NO3- 50Nitrite as NO2- 3Selenium 0.01* For very low concentrations, laboratory results are reported in μg/L or ppb. Note the conversion: 1 mg/L (ppm) = 1000 μg/L (ppb)Table 5.18 Organic constituents of health significance to drinking waterParameter* Maximum Value** µg/L (ppb)Polychlorinated biphenyls (PCBs) 0.5Benzene 10Disinfection-by-productTrihalomethanes 250Pesticides2,4 D 30Aldrin and Dieldrin 0.3Carbofuran 10Chlordane 0.2DDT 20Dichlorvos 1Dimethoate 6Endosulfan 30Endrin 0.6Glyphosate 10Heptachlor 0.3Hexaclorobenzene 1Methyl parathion 0.3Mevinphos 5Monocrotophos 1Paraquat 30Parathion 10Permethrin 20* Routine monitoring for organic constituents (Table 3) is not required unless there is a potential for contamination of water supplies.** For very low concentration, laboratory results are reported in μg/L or ppb. Note the conversion: 1 mg/L (ppm) = 1000 μg/L (ppb)Table 5.19 Physical and chemical quality: aesthetic qualityParameter Maximum Value, mg/LTaste AcceptableOdor AcceptableColor 5 TCUTurbidity 5 NTUResidual chlorine 0.2-0.5pH 6.5 – 8.5 (no unit)Aluminum 0.2Ammonia 1.5Study and Design Guidelines I-147
    • Part 5: Study and Design GuidelinesChloride 250Copper 1Hardness* 300Hydrogen Sulfide 0.05Iron 0.3Manganese 0.1Sodium 200Sulfate 250Total dissolved solids** 800Zinc 3* Hardness is expressed as mg/L CaCO3** Conductivity (μS/cm) can also be measured and it is roughly equivalent to twice the TDS value.Table 5.20 Priority parameters in small water suppliesParameter* Maximum ValuepH 6.5-8.5Turbidity 5 NTUArsenic 0.05 mg/LIron 0.3 mg/LTotal Dissolved Solids (TDS) 800 mg/LThermotolerant Coliforms or E. coli 0 per 100 mL* Additional parameters such as conductivity can be monitored but these are the minimum requirements.5.5 Education Facilities: Group 104Only limited design guidance is provided for education facilities. This is because educationprojects are predominantly building work. Brick schools are standard MoEYS designs withsome minor modifications to comply with C/S Fund requirements and specifications. TheWooden school design is the same as used under the Seila Program, except for some minorchanges to improve the building quality. Water supply and sanitation works are provided asoutputs under the Water Supply (103) and Sanitation (110) groups. Ancillary works such asgates and fences may be provided according to the project requirements. Special educationbuildings may require specific designs.Form T41 is used. The form is designed for a complete education facility project, it incorporatesall of questionnaires related to education, but it allows only one output per form. Typically aschool project could require several outputs in addition to the basic classrooms, e.g. furniture,latrines, rainwater tanks, a well, yard, fence, wall and gate. All school outputs can be preparedby using the same form -Form T41, yet there must be one form T41 for each output becauseone form can only provide one set of associated templates drawings and quantity table; addform T101 water supply and T31 sanitation for the outputs of latrines, rainwater tanks and wells.Quantity of proposed outputsThe proposed outputs you have selected need to be quantified in number or length beforeproceeding to complete the form.Information about education requirementsThe questions provide information on the number of students, existing classrooms, availabilityof teachers and provision for community management. The answers should be considered forappropriateness of the project and its sustainability. The responsibility for operation andmaintenance of Education Facilities is normally passed to the line agency, the ProvincialDepartment of Education.Study and Design Guidelines I-148
    • Part 5: Study and Design GuidelinesPhysical characteristics of the siteThere are questions to establish whether the site floods, and whether this is seasonal deepwater flooding, or due to slow drainage after heavy rainfall. Essentially if there is a floodproblem the decision has to be made whether this can be dealt with by drainage ditches orother means so that a standard 0.5 m plinth classroom design can be used. If the problem offlooding cannot be controlled then higher floor levels will be needed, either 1.5 or 2.5 m plinths,2.5 or 3.5 m piers.There are a series of questions intended to confirm suitability of the site. These include whetherit is free of UXO, status of the land title, boundary demarcation and whether the site is ofsufficient size. The existing water supply and sanitation provisions should be determinedbecause water supply and sanitation outputs may be needed.Foundation soilsForm T41 provides for ground investigation by trial pit and DCP, as many pits and tests as areneeded. Form T41 creates in advance the trial pit log; you enter the soil type and the depths at which the soil types change. The 20 percentile value for DCP needs to be calculated and filled into the form. You can use Applet T11 for the calculation. Templates drawings are currently for 0.5 m plinth 3 classroom wooded schools and 5 classroom brick schools. However, Form T41 automatically calls-up the correct quantities within the project generator according to the number of classrooms and options chosen. For a site specific output such as a fence the quantity will have to be measured.For some outputs such as higher floor levels there may be no Template design. In these casesa design and quantities will have to be provided.5.6 Health Facilities: Group 105Only limited design guidance is provided for health facilities. This is because health projects arepredominantly building work. Brick and wooden health post designs are MoH standard designswith some minor modifications to comply with C/S Fund requirements and specifications. Watersupply and sanitation works are provided as outputs under the Water Supply (103) andSanitation (110) groups. Ancillary works such as gates and fences may be provided accordingto the project requirements.Form T51 is used. The form is designed for a complete health facility project; it incorporates allof questionnaires related to health facilities, but it allows only one output per form. Typically ahealth facility could require several outputs in addition to the basic building, e.g. latrines,rainwater tanks, a well, fence, wall and gate and access culvert. All of health facility outputs canbe prepared by using the same form - Form T41, yet there must be one form T51 for eachoutput because one form can only provide one set of associated templates drawings andquantity table; add form T101 water supply and T31 sanitation for the outputs of latrines,rainwater tanks and wells.Quantity of proposed outputsThe proposed outputs you have selected need to be quantified in number or length beforeproceeding to complete the form.Information about health requirementsThe questions provide information on the population that will be served by the facility and thedistance they will have to travel. If you do not know the distances use MangoMap to measuresthem between the facility site and village centres. There are also questions about availability ofStudy and Design Guidelines I-149
    • Part 5: Study and Design Guidelinestrained staff and who will provide these staff. The answers should be considered forappropriateness of the project and its sustainability. The responsibility for operation andmaintenance of Health Facilities is normally passed to the line agency, the ProvincialDepartment of Health.Physical characteristics of the siteThere are questions to establish whether the site floods, and whether this is seasonal deepwater flooding, or due to slow drainage after heavy rainfall. Essentially if there is a floodproblem the decision has to be made whether this can be dealt with by drainage ditches orother means.There are a series of questions intended to confirm suitability of the site. These include whetherit is free of UXO, the status of land title, boundary demarcation and whether the site is ofsufficient size. The existing water supply and sanitation provision should be determinedbecause water supply and sanitation outputs may be needed.Foundation soilsForm T51 provides for ground investigation by trial pit and DCP, as many pits and tests as areneeded. Form T51 creates in advance the trial pit log; you enter the soil type and the depths at which the soil types change. The 20 percentile value for DCP needs to be calculated and filled into the form. You can use Ms. Excel for the calculation. Form T51 automatically calls-up the correct quantities within the project generator according to the outputs chosen. For a site specific output such as a fence the quantity will have to be measured.5.7 Market Construction: Group 106No design guidance is provided for market construction.5.8 Crop Storage and Processing: Group 107No design guidance is provided for crop storage and processing.5.9 Social Infrastructure: Group 108No design guidance is provided for social infrastructure.5.10 Energy: Group 109No design guidance is provided for energy.5.11 Sanitation: Group 110Form T101 is used for sanitation projects.The sanitation group includes: x Latrines x Waste water x Solid waste management x (Storm water) DrainageStudy and Design Guidelines I-150
    • Part 5: Study and Design Guidelines5.11.1 LatrinesIn the case of schools there should be two latrines for every 5 classrooms; template designs areavailable for two and four latrines. Health posts should be provided with a two room latrinebuilding, one room provides a toilet, the second room provides a shower.5.11.2 Waste water and solid wasteThere is no design guidance for waste water treatment and solid waste management; specialistadvice should be sought for these outputs.Waste waterWaste water is a mixture of toilet waste (excreta) and sullage. Sullage is household wastewhich has been used for washing, cooking or cleaning purposes, it is sometimes known as‘grey water’. Modern practice is to provide separate drainage systems for wastewater andsurface water runoff. If a wastewater system is provided it will be under sub-group 11002.However more often, and especially in villages and peri-urban areas, only surface waterdrainage will be provided. As discussed at section 5.11.3 below in these circumstances thedrains will also remove sullage.5.11.3 DrainageThe objective of drainage is to remove unwanted water from settlements in a controlled andhygienic manner in order to minimise public health hazards, inconvenience to residents anddeterioration of other infrastructure. This requires: x the removal of surface water, that is, water which runs off the land and buildings as a result of rainfall; and x the removal of sullage, that is, household wastewater which has been used for washing, cooking or cleaning purposes but which does not contain excreta.Sullage increases the potential of pollution by the drainage system. The risk is greatest whenthe proportion of sullage water is high, as occurs during the dry season. If drains convey sullage, pay attention to the location of wells and water supply sources. It may be necessary to protect these by extending the length of piped or lined drain to outfall a safe distance away. The safe distances quoted on Table 5.13 should be applied. Under no circumstances allow toilet waste and excreta into the surface water drainage system because it will create a serious health risk. Promote the use of latrines.Capacity of drainIn order to calculate the required capacity of the drain it is necessary to establish the catchmentfor a drain. In a peri-urban or village centre location there are building frontages and roofsdischarging to the strip of land beside the road. If a roadside drain is proposed it isrecommended to allow for drainage of a strip extending 50 m back from the road. In suchlocations it is normal to provide a drain both sides of the road, if a drain is only provided oneside of the road consider whether it will capture some water from both sides of the road andadjust the area accordingly.Form T101 uses a default value of 3.5 l/s/ha to estimate the runoff from land beside the drain.This is the same as used for irrigation drainage. This figure comes from an analysis typicalrainfall in Cambodia that is only exceeded by very heavy storms that occur occasionally,perhaps several times in one year, not at all in others. Therefore if drainage is provided for thisrunoff, there may be local flooding for short periods on a few occasions but most of the time thedrains will be large enough. This is a compromise to reduce the cost of the drains. The formStudy and Design Guidelines I-151
    • Part 5: Study and Design Guidelinesallows another value to be entered. The required capacity is then calculated manually andenter to the form.Form T101 asks if the drain collects water from beyond the immediate area, e.g. a small area ofpaddy. If it does you are asked to describe how the drain is affected, e.g. you may find that thewater from the paddy must be added to the runoff within the village. It is also necessary toenter the extra area of catchment. If the area is ”1 km2 then the form will calculate the extraflow based on 3.5 l/s/ha (or whatever other flow rate you enter) and adds it to the runoff frombeside the drain. If the area is >1.0 km2 then the form advises the flow is probably too large forthe drain and should be directed to flow another way.Hydraulic design of channelDifferent procedures apply for the hydraulic design of channels compared to pipes. The adviceon pipes follows below.The theory for design of channels is the same as irrigation canals and drains. Form T101 calls-up Applet T101 Channel drain that will choose the channel size provided you answer a few questions. You then need to fill the results into the generator.You have to enter the level of the bed at the upstream and downstream ends plus the length ofthe drain so that the Applet can calculate the gradient. You choose a bank slope, the Templatefor a concrete or brick drain has vertical sides. You select a bed width. You also chose afreeboard, 0.1 m is recommended as the minimum freeboard but you can choose a largerfreeboard. You enter Manning’s n for channel roughness, the form lists recommended valuesfor earth, concrete and masonry. You then need to enter the required capacity previouslycalculated manually and write into the form to the Appet T101 but you may enter another flow ifyou chose.Applet T101 then prints the required depth of drain, the width between top of banks (which isthe same as the bed width except for trapezoidal drains), and the flow velocity. If therecommended dimensions are not suitable then you can try changing the bed levels and thebed widths to see if this will improve the design. Finally, copy those results to the form T101.Hydraulic design of pipe drainPipe design is based on solution of the Colebrook-White formula. The full solution is toocomplex to provide rapid solution for design so ‘Universal’ design charts were developed byAckers22 to permit direct solution. These are now in their 8th Edition in tabular form23. The relevant results have to be taken from the charts to fill into Form T101.The results used by Form T110 are show in Table 5.21 and Table 5.22 for concrete and plasticspipes respectively. The form allows you to choose between these two pipe materials. Thedifference is the pipe roughness (friction) expressed as the Colebrook-White coefficient k (seetables). Plastic pipes are smoother so have a marginally greater capacity.At design capacity the pipes are intended to run full. For this condition the headwalls in theintermediate chambers must be submerged. Hence the hydraulic gradient is calculatedassuming the water rises to 200 mm below ground level at the head of the drain and is thedepth of the drain at the outfall. The applet then enters the table for this gradient and reads offthe discharge and velocity for the chosen pipe size. If this does not match the required capacitychose a different pipe size, or alter the drain depth to change the gradient until you are satisfiedthe drain will be large enough.22 Ackers P. Charts for Hydraulic Design of Channels and Pipes, Hydraulics Research Paper No2, Hydraulics Research Station, Wallingford, Her Majesty’s Stationery Office, UK, First Edition, 1958.23 Barr DIH. Tables for Hydraulic Design of Pipes, Sewers and Channels, Eighth Edition, Volume 1. HR Wallingford, UK, March 2005.Study and Design Guidelines I-152
    • Part 5: Study and Design Guidelines The best pipe size is a compromise. Most of the time the drain will convey small flows. Small flows will deposit sediment and rubbish, especially if the flow includes sullage. The larger the drain, the more likely it is that sediment deposits will build up. Some of the sediment will be washed away by storm flows if velocity is above about 0.5 m/s. But an oversize drain will require frequent cleaning whereas a too small drain will often overtop and cause localised flooding.5.12 Flood Protection Structures: Group 111No design guidance is provided for flood protection structure.Table 5.21 – Pipe full flow and velocity for concrete pipes USE THIS TABLE FOR CONCRETE PIPES (k = 0.3 mm) Pipe Pipe Pipe Pipe Pipe PipeHydraulic gradient diameter diameter diameter diameter diameter diameter 0.3m 0.4m 0.5m 0.6m 0.8m 1.0m Discharge Discharge Discharge Discharge Discharge Discharge Velocity Velocity Velocity Velocity Velocity Velocity (m/s) (m/s) (m/s) (m/s) (m/s) (m/s) (l/s) (l/s) (l/s) (l/s) (l/s) (l/s)0.003 6 0.08 12 0.10 24 0.12 37 0.13 80 0.16 145 0.180.004 7 0.10 15 0.12 27 0.14 42 0.15 95 0.19 165 0.210.005 8 0.11 16 0.13 30 0.15 47 0.17 108 0.21 195 0.250.006 9 0.12 18 0.14 33 0.17 53 0.19 120 0.24 215 0.270.007 10 0.13 20 0.16 36 0.18 58 0.21 131 0.26 235 0.300.008 10 0.14 22 0.18 39 0.20 62 0.22 139 0.28 250 0.320.009 11 0.16 23 0.18 42 0.21 66 0.23 144 0.29 260 0.330.010 12 0.16 24 0.19 45 0.23 70 0.25 150 0.30 270 0.340.012 13 0.18 27 0.21 48 0.24 78 0.28 170 0.34 310 0.390.014 14 0.20 29 0.23 51 0.26 85 0.30 180 0.36 330 0.420.016 14 0.20 31 0.25 55 0.28 90 0.32 200 0.40 350 0.450.018 15 0.21 33 0.26 59 0.30 96 0.34 210 0.42 375 0.480.020 16 0.23 35 0.28 63 0.32 102 0.36 220 0.44 400 0.51Table 5.22 - Pipe full flow and velocity for plastics pipes USE THIS TABLE FOR PLASTICS PIPES (k = 0.003 mm) Pipe Pipe Pipe Pipe Pipe PipeHydraulic gradient diameter diameter diameter diameter diameter diameter 0.3m 0.4m 0.5m 0.6m 0.8m 1.0m Discharge Discharge Discharge Discharge Discharge Discharge Velocity Velocity Velocity Velocity Velocity (m/s) (m/s) (m/s) (m/s) (m/s) (l/s) (l/s) (l/s) (l/s) (l/s) (l/s)0.003 6 0.08 13 0.10 24 0.12 38 0.13 88 0.18 160 0.200.004 7 0.10 16 0.13 28 0.14 46 0.16 102 0.20 180 0.230.005 8 0.11 18 0.14 32 0.16 51 0.18 117 0.23 200 0.250.006 9 0.12 20 0.16 35 0.18 56 0.20 126 0.25 220 0.280.007 10 0.13 21 0.17 38 0.19 61 0.22 136 0.27 240 0.310.008 10 0.14 23 0.18 41 0.21 66 0.23 146 0.29 260 0.330.009 11 0.16 24 0.19 44 0.22 71 0.25 154 0.31 280 0.360.010 12 0.17 26 0.21 47 0.24 76 0.27 160 0.32 300 0.380.012 13 0.18 29 0.23 50 0.25 82 0.29 175 0.35 330 0.420.014 14 0.20 31 0.25 55 0.28 91 0.32 200 0.40 360 0.460.016 15 0.21 33 0.26 60 0.31 99 0.35 215 0.43 390 0.500.018 16 0.23 36 0.29 65 0.33 106 0.37 230 0.46 420 0.530.020 18 0.25 39 0.31 69 0.35 114 0.40 250 0.50 450 0.57Study and Design Guidelines I-153
    • ANNEX 1:TECHNICAL FORMS I-154
    • Annex 1: Technical FormsTechnical Form T11 – Transport: RoadsForm T11 Transport: Road Province : District : S/C: Name of project : Code of S/C : Name of TSO : Date of form preparation : 1. Location: where is the earth road located within the Sangkat/Commune? * Describe this location 2. Give the coordinates of GPS If there are many road segments which have the same condition width and pavement, give the coordinates of start points and end points of each segment. One row is for one segment. Start point Ending point X of GPS Y of GPS X of GPS Y of GPS 3. Type of road project: What kind of road work is required? New road construction Rehabilitate existing road, the same width and surface Improve and widen existing road, same surface Improve existing road, the same width upgraded surface Improve and widen existing road, upgrade surface. 4. Length of road: what is the length of the road (in kilometer)? 5. Road classification: District to district road, Tertiary Road, (T Road), “6.0 m” District to Sangkat/Commune, Sub-tertiary Road Type 1, ( ST1 road) “6.0 m” Commune to commune road, Sub-tertiary Road Type 2, (ST2 road), “5.0m” Commune to village road, Sub-tertiary Road Type 3, (ST3 road), “4.0m” Village to village road, Sub-tertiary Road Type 3, (ST3 road), “4.0m” 6. Structures: are there existing structures? * If “yes” answer the following questions; if “no” skip to the next question. Yes No 7. List number, description and dimensions of existing structures. 8. What new structures are required (number of each)? * fill a form T12 for each structure, number the structure in the table.Study and Design Guidelines I-155
    • Annex 1: Technical Forms Bridge culvert drift vented causeway 9. Type of existing road: is there existing path, car-track or road ? Yes No 10. Is the road on an embankment? Yes No 11. What is the width of the road? 12. Condition of road: what is the condition of the road? * first row for rainy season, the second row for dry season. Write “Can” or “Cannot”. Can: Can go, Cannot: Cannot go. Bicycle Motorcycle Motor- Koyun or Car or truck heavy truck remorque small truck for carrying for carrying for carrying people goods goods 13. Main cause of road damage: What causes the main damage? If “Something else”, answer the below question Flooding Ponding on the road surface Gully erosion from runoff from the surface Carts pulled by animals Small cars or pickup trucks Heavy trucks for carrying goods Something else (fill in the below question) 14. Others main causes: 15. Material availability for road construction. Remark: For the material which are required for road construction for the road type you have chosen skip to others questions! 16. Fill material from roadside borrow as dug: Meets specification requirements for Type 3 Fill Meets specification requirements for Type 1 Can meet specification for Type 3 material by mixing with imported material Can meet specification for Type 1 material by mixing with imported material Is unsuitable material (mud, organic soils or Peat). 17. Fill material from remote borrow pit: Meets specification requirements for Type 3 FillStudy and Design Guidelines I-156
    • Annex 1: Technical Forms Meets specification requirements for Type 1 18. Distance of borrow pit(s) from road (Km): 19. Source of sand: Borrow pit Stream bed 20. Distance from road (Km): 21. Source of gravel: Borrow pit Stream bed 22. Distance from road (Km): 23. Laterite Put “good”, “medium” or “poor” in the box of quality. Source distance of transportation quality (Km) 24. Type of stone from quarry * It the source is not borrow pit, please choose the answer below Hard metamorphic rock (granite, basalt, etc) Limestone Sandstone 25. Type of stone for stream bed: * If the source is not stream bed, please choose the answer below Hard metamorphic rock (granite, basalt, etc) Limestone Sandstone 26. Water supply for earth work Source distance from road (Km) 27. Road traffic: what are the proportion of the cars and trucks using the road? *Write in percentage. One place to another in Go from the commune to Go from one place commune a place outside the outside the commune to commune or vice versa another outside the commune 28. the proportion of the cars and trucks using the road is: * Put it into percentage. Belong to people who live in the Belong to people who live outside the commune commune 29. Foundation soils: what kind of soil the structure stand on?Study and Design Guidelines I-157
    • Annex 1: Technical Forms * if “other”, mention in the following question: Soil that is very easily eroded Normal clay Sandy soils Gravels Earth with big stones in it Other. 30. For others soil kinds. 31. Side slope: Fill slope Vertical Horizontal 32. Cut slope Vertical Horizontal 33. Choice of road: what is thickness of the pavement proposed? Surface (if applicable) Wearing course (if applicable) Base course (if applicable) Road base (if applicable) Sub base (if applicable) 34. Fill with the thickness of the road pavement choosing above: Road pavement thickness 35. Road maintenance: Does the commune have a Commune Road Sub-Committee? Yes No 36. Who is responsible for road maintenance? * if “Other” mention your answer in the question below. Ministry of Rural Development Sangkat/Commune Others 37. Write the person who is responsible for road maintenance if you choose “other” 38. Remark: You must upload “Applet” in which you entered your data to get the answers and the advices about road pavement. If you chose the road pavement that is not suitable less or more than recommendation from “Applet T11”, give your reason on Advice Tab.Study and Design Guidelines I-158
    • Annex 1: Technical FormsTechnical Form T12 – Transport: StructuresForm T12 Transport : Road structure Province : District : S/C: Name of project : Code of S/C : Name of TSO : Date of form preparation : 1. Location: where is the structure located within the Sangkat/Commune? *Describe the location 2. Give the coordinates of the GPS. X of GPS Y of GPS 3. Road Classification : * Road classification: T, ST1, ST2, or ST3. *Road standard: A or B Classification Road standard Width of pavement (m) 4. Scope of work: is the structure part of a road project to be carried out at the same time or is the work for the structure only? A part of road project Structure only. 5. Is there an existing structure and if so what is its condition and description? If “Yes”, answer only the questions about the existing structure, then go to question 13. If “ No” go directly to question 13. Yes No 6. Describe of existing pipe culvert: * Material can be: Concrete, Clay, Plastic or steel. Headwalls can be: wood, masonry, mass concrete, Reinforced concrete, or none. Number of pipe diameter (m) Pipe material Headwalls Carriageway width over culvert 7. Describe the existing box culvert. * Headwall can be: Wood, masonry, mass concrete, reinforced concrete or none. Road slab can be: on wall or integrated with wall.Study and Design Guidelines I-159
    • Annex 1: Technical Forms Number of Width (m) Height Walls Road slab Carriage box width over culvert 8. Describe the existing concrete bridge. * Abutment material can be: wood, masonry, mass concrete, reinforced concrete, none. The piers can be: concrete on footing, concrete on piles. Deck material can be: wood or reinforced concrete. Number of Width of Height of Abutment Piers Deck Deck spans each each span material material carriageway span width(m) 9. Describe the existing steel bridge. * Steel bridge can be: Bailey, Vietnamese or others. Abutment material can be: wood, masonry, mass concrete, reinforced concrete or none. The piers can be: wood on footing, wood on piles, steel on footing, steel on piles, concrete on footing or concrete on piles. The deck can be: wood or steel plates. Type Number Width of Height of Abutment Piers Deck Deck of spans each each material material carriageway span span width(m) 10. Describe the existing wooden bridge. * Abutment material can be: wood, masonry, mass concrete, reinforced concrete, none. The piers can be: wood on footing, wood on piles. Deck material can be: wood or steel plate. Number of Width of Height of Abutment Piers Deck Deck spans each each span material material carriageway span width(m) 11. Describe the existing drift. *Road material can be: earth or laterite, stone, concrete or others. Width of ramp slope Difference in level road material carriageway crossing (m) between road on width (m) embankment and crossing (m) 12. Describe the existing vented causeway. Road material can be: earth or laterite, stone, concrete or others. Width of ramp Difference in road carriageway Size of Size of crossing slope level between material width (m) opening opening (m) road on Width/Dia Height embankment and crossing (m) 13. What is the condition and cause damage of the structure? Good, no restriction on traffic (age of structure) Poor, most 4 wheel traffic can cross with care (bad design, material or construction)Study and Design Guidelines I-160
    • Annex 1: Technical Forms Bad, impassable to 4 wheel traffic (not suitable for current traffic) Collapsed and useless (damage by water or flood) 14. Available construction material: Part 1 * For construction material, fill with “Need” below type of material, then fill the source and distance. If “No need”, fill nothing. Source of fill type 3: borrow pit. Source of sands: borrow pit or stream bed. Source of gravel: borrow pit or stream bed. Type source distance sand source distance gravel source distance 3 fill (km) of (km) of (km) sands gravel 15. Part 2 * Source of stone: quarry or stream bed. Type of stone: hard metamorphic rocks (granite, basalt, etc). Stone Source of type of distance water source distance stone stone (km) supply for (km) concrete 16. Foundation soils: What kind of soil is the structure founded on ? * if “others”, answers the following questions. Soil that is very easily eroded Normal clay Sandy soil Gravel Earth with big stone in it Others 17. Others, mention them. 18. Foundation strength of DCP (mm/blow) and location of each test. * Location: stream bed road centre line, stream bed upstream, stream bed downstream, left bank abutment, right bank abutment or others. DCP (mm/blow) location 19. what is the 20 percentile DCP? 20. Hydrology and required hydraulic capacity of structure: did you use “Applet” to calculate the design flow, velocity, type and size of structure? * You can use “Applet T12” to determine the simple flow system, but for theStudy and Design Guidelines I-161
    • Annex 1: Technical Forms complicated one, you have to find help from an engineer. Yes No 21. Maximum design flow (m3/s) from Applet or engineer is: * If you use Applet, write down the answer from form T12, worksheet GTFM:C32. 22. Velocity (m/s) which downstream structure can withstand is * if you use Applet, write down the answer from form T12, worksheet GTFM:C34 23. Remark: Upload “Applet” in which you fill the data to get the design flow, suitable structures and the velocity above. If you don’t use Applet to get the recommended structure, give your suitable reasons and upload the related documents that you use to determine design flow and velocity.Study and Design Guidelines I-162
    • Annex 1: Technical FormsTechnical Form T21 – Irrigation: ProjectForm T21 : Irrigation projet Province : District : S/C: Name of project : Code of S/C : Name of TSO : Date of form preparation : 1. Location: where is the project located within the Sangkat/Commune? 2. Give the coordinate of GPS. X of GPS Y of GPS 3. Project description: provide the description about the project including the proposed components and size of command area. 4. Farmer water user community: is there a farmer user community to support the project? * if you chose “No”, skip to question 7. Yes No 5. How many farmers (families) are members of the Community? 6. Have the farmers discussed together and agreed how they will pay the operation and maintenance costs of the project? Yes No 7. Operation and maintenance responsibilities: Who will be responsible to do the operation and maintenance? * if the scheme don’t need a pump, fill with “No need”. Operate the Open and close Collect Organize Solve disputes pump (if the water gates? water user maintenance between scheme needs fees? work? farmers about a pump)? the water? 8. Irrigation system requirement: what is the irrigated area in hectares? * Remark: if the project will be a part of a big irrigation project, only describe the part that will be affected by the project. Wet season dry season 9. What is the main type of crop that will be grown on the land? wet season dry season 10. How much of the land that has enough water every year already? Wet season number of families dry season number of families 11. How much of the land that has enough water some years? Wet season number of families dry season number of families 12. How much of the land never has enough water at present? Wet season number of families dry season number of families 13. Total size of land and total number of families. * Totalize the size of wet season irrigated area, the number of families, the size of dryStudy and Design Guidelines I-163
    • Annex 1: Technical Forms season irrigated area, the number of families. Wet season number of families dry season number of families 14. Flooding: Do the fields flood for some days each year? If “Yes”, answer the following questions, if “No”, skip to question 18. Yes No 15. How long are the fields flooded (days)? 16. What is the flood depth during these days (m)? 17. What is the flood path, does the water flow concentrate is some places, describe and flow path(s) on map? 18. Existing irrigation system: is there and existing irrigation system? If “Yes”, answer the following question. If “No” skip to question 28. Yes No 19. When was the irrigation system built? If ‘1980 to 2000’ or ‘After 2000’, answer the following questions. If not, skip one question below. French era Sihanouk era Khmer Rouge era 1980 to 2000 After 2000. 20. Under what program or which donor paid for the project? 21. Does the system work? Working Working 50% Works a little Not working 22. What are the main components of the system and what is their condition? River intake Reservoir Dam Spillways Large water gates Canals Small water gates and culverts 23. What is the condition of the irrigation project? Answer: Working, works a little, Not working or collapse for the main components of theStudy and Design Guidelines I-164
    • Annex 1: Technical Forms system choosing above. Main components of the system condition 24. How many months is water available? < 1 month 1 to 2 months 3 to 4 months 5 months 6 months > 6 months 25. What do you judge as the main problem with the existing irrigation system? 26. How can a new irrigation project overcome these problems? 27. Do you have any other comments relevant to the proposed irrigation project? 28. Water resource: where will the water come from? River Reservoir Flood lake Canal 29. What is the water depth existing river, reservoir, lake or canal each month of the year and is the water stationary or flowing (include largest river flowing into or out of an existing reservoir)? Month depth (m) flowing, not flowing 30. How will the water be delivered from the source to the distribution canals and fields? By pumping By gravity 31. What is the difference in between the lowest water level at the source and the level of the fields (m)? * It is recommended to measure the difference in level with a survey instrument. 32. Irrigation water requirement: remark Use “Applet T21” to get “monthly water requirement for irrigation” and “gravity flow capacity per second”. 33. Works proposed for irrigation project: What are the main works items include size that will be repaired or newly constructed for the Irrigation Project? * For these following questions, answer only about situation and size of the structures chosen in this question. Reservoir Dam Spillways River weir or gate Head regulator Secondary canalStudy and Design Guidelines I-165
    • Annex 1: Technical Forms Tertiary canal Canal, water gate or regulator Off-take Culverts 34. Reservoir works Repair or New Area (ha) Volume (m3) 35. Dam works * Fill the questionnaire form T22 Repair or New length (m) maximum height (m) 36. Spillways works * Fill the questionnaire form T23 Repair or New length (m) drop (m) 37. River weir or gates Repair or New length (m) height water raised (m) 38. Head regulator works * Fill the questionnaire form T23 Repair or New Number gate size (m) 39. Secondary canal works * Fill the questionnaire form T22 Repair or New Number Length (m) 40. Tertiary canal works * Fill the questionnaire form T22 Repair or New Number Total Length (m) 41. Canal water gates or regulators work * Fill the questionnaire form T23 Repair or new number 42. Off-take works * Fill the questionnaire form T23 Repair or new number 43. Culvert works * Fill the questionnaire form T23 Repair or new number size (m) with gate or not 44. Remark: Upload “Applet T21” that you’ve used into the Project Generator!Study and Design Guidelines I-166
    • Annex 1: Technical FormsTechnical Form T22 – Irrigation: EarthworkForm T22 Irrigation earthworks Province : District : S/C: Name of project : Code of S/C : Name of TSO : Date of form preparation : 1. Location: where is the project located within the Sangkat/Commune? Location description: 2. Provide the coordinate of GPS. * First is the starting point, the flow row is the ending point X of GPS Y of GPS 3. What type of earthwork is required? Build a new earthwork Improve the existing earthwork earthwork (e.g. raise or deepen, widen, add road surfacing) Repair a badly damage earthwork Periodic maintenance 4. Traffic use of earthwork: Is the earthwork used as a public road or for farm access? If “Not used” skip to question 11. Public road Farm access Not used 5. Has the earthwork ever had Laterite or any other kind of improved surface in the past? Yes No 6. Is there any Laterite or any other kind of surface on the earthwork now? Yes No 7. What is the largest vehicle that uses the earthwork? Passenger car People walking Motorcycle Motor-remorque Bicycle Animal cart Light vehicle/van KoyunStudy and Design Guidelines I-167
    • Annex 1: Technical Forms Medium truck (6 tyres) Heavy truck (6 tyres) Bus (>4 tyres) Mini-bus (4 tyres). 8. Approximately how many of these vehicles use the earthwork per day? * In PCU units, you can use Applet T11 to help your calculation of the number of vehicle. 9. According the traffic of vehicle above, what type of pavement is suitable for this earthwork? * if the number of vehicle is < 21 ‘Earth surface is satisfactory’. * if the number of vehicle is < 25 ‘Light Laterite surface is satisfactory’ * If number of vehicles is <100 ‘Medium Laterite surface is satisfactory’ * If number of vehicles is >100 ‘Too much traffic for Laterite surface consider other option’. 10. Condition of the existing dams or dykes and Canals or drains: describe the condition of the existing earthwork. 11. What causes most damage to the earthwork? * if “Other”, answer the question 12 Dam: traffic, people or animal Erosion from rain Wave damage from reservoir of flooding Flooding overtopping and breaching Flooding overtopping and breaching Water flow along channels at toe or structures Others Canal: too small for flow Blocked by weed Silted-up Bank erosion 12. If “Others” mention them. 13. Soils: What kind of soil is at the project site, (a) for use as fill, (b) for excavating canals and drains? Clay group, stable slope: upstream 1:2.00, downstream 1:1.75, Canal and drain 1:1.25 Sandy group, stable slope: upstream 1:2.50, downstream 1:2.00, Canal and drain 1:1.50 Silty soil, stable slope: upstream “not suitable”, downstream “not suitable”, Canal and drain 1:1.50 Dispersive clay, upstream “not suitable”, downstream “not suitable”, canal andStudy and Design Guidelines I-168
    • Annex 1: Technical Forms drain : Line canal Organic soils, upstream “not suitable, downstream “not suitable”, canal and drain : Line canal. 14. Material for road construction: remark Skip the materias which are not chosen for road construction. 15. Fill material from borrow beside earth works. Meets the specification requirement for type 3 fill Exceeds specification for Type 3 Fill with high clay content 16. Fill material from remote borrow pit * fill material can be 1. Meets the specification for type 3 fill, 2. Exceeds specification for type 3 fill with high clay content. Suitability, source (km). Suitability source (km) 17. Sands * Source: borrow pit, stream bed. Source distance (km) 18. Gravel * Source: borrow pit, stream bed .Source distance (km) 19. Laterite * Source: borrow pit, stream bed. Quality: Good, medium or poor. Source Quality distance (km) 20. Stone * Source: quarry, stream bed. Type: granite, basalt, limestone… Source type distance (km) 21. Water supply for earthwork Source distance (km) 22. Design of dam and dyke: What is reservoir full supply level at dam or flood levels at dyke (m)? 23. What freeboard will be allowed (m)? * You can get the values of freeboard from PIM. 24. Dam or dyke crests level (before any road surface is added), (m). 25. Will the dam or dyke be used as a road? 26. What is the crest width? 27. Will the crest be surfaced? If “Others”, answer the following question. Not surfaced Laterite Others 28. Others, mention them. 29. If laterite, what is the thickness of laterite (mm) ? 30. What will be the upstream slope (see advice in question 13)? 31. What will be the downstream slope (see advice in question 13)? 32. What slope protect will be provided to the upstream slope? * If not “Rock riprap”, skip the question 34 to 36.Study and Design Guidelines I-169
    • Annex 1: Technical Forms None Grass Rock riprap Others 33. If “Others”, mention them. 34. If “Rock riprap”, What class of riprap (Class A suitable for small reservoirs)? Class A Class B Class C Class D 35. What thickness of riprap in millimeters (300 mm minimum for Class A)? 36. What filter will be placed below riprap? 150mm gravel 50mm sands over geotextile 37. What slope protect will be provided to the downstream slope? None Grass 38. Capacity of canal: Will the canal be irrigated continuously (24 hours) by gravity or by pumping? If “Gravity”, answer the question 40, then skip the question 41. If “Pumping”, skip the question 41, then answer the question 41. Gravity Pumping 39. Required flow capacity (gravity). * the design peak flow rate : 2l/s/h or another higher flow rate. * flow capacity (l/s) = irrigation area (ha) x flow rate (l/s/ha) Flow rate (l/s/ha) irrigation area (ha) flow capacity (l/s) 40. Required flow capacity (pumping) * Recommended flow rate is 2l/s/ha, or another higher flow rate. * Pumping rate = flow rate / number of pumping hours x24hours * flow capacity = irrigation area (ha) x flow rate (l/s.ha) Flow rate (l/s/ha) number of pumping hours pumping rate (l.s.ha) (hour) 41. Capacity of drain: How will the fields be drained? If ‘Irrigation canals provide drainage’ the canals must be sized (larger) top work as drains. So you have to carry on the question about the drain. If “No drain”, explain the following question, and then skip to question 48. Separate drain Canal as a drain No drainStudy and Design Guidelines I-170
    • Annex 1: Technical Forms 42. Explain how excess rainfall and flood water will be drained from the fields? 43. Drain capacity * Recommended flow rate 3.5l/s/ha, or another higher flow rate. * Flow capacity (m3/s) = area (ha) x flow rate (m3/s/ha) Drainage area (ha) flow rate (l/s/ha) flow capacity (m3/s) 44. Will the drain collect water from catchments beyond the fields? * E.g. a stream flows into the head of the drain from a small catchment or another irrigation system? If “Yes”, answer the following questions, if “No” skip to question 48. Yes No 45. What is the catchment area in km2? If the catchment < 1.00km2 , Add this area to the area of fields above and recalculate new field drainage flow rate. If the catchment > 1.00km2, use “Applet form T22, flow external catchment” or get help from engineer to calculate the total flow (with the flow in the catchment above). 46. The flow rate of external catchment (m3/s) is: Use “Applet T22 external catchment” then copy form column C32. If the flow system of the external catchment is too complicate, you have to discuss with the engineer to get the flow capacity of this catchment. 47. Total drain design flow (m3/s) is the flow from irrigated area + flow from external catchment. * Value of question 43 + value of question 46. 48. Hydraulic design of canal and drain: remark Use “Applet T22 Hydraulic design of canal and drain” to calculate the minimum water height, bottom width and design velocity. 49. Responsibility for operation and maintenance: is there a Farmer Water Use Comity (FWUC) or similar group of people who are responsible for operation and maintenance of the earthwork. Yes No 50. Who will take to operate and maintain the earthwork ? 51. Remark Upload all of “Applet T22” that you used into “Project generator” for engineer to examine.Study and Design Guidelines I-171
    • Annex 1: Technical FormsTechnical Form T23 – Irrigation: StructureForm T23 Irrigation structure Province : District : S/C: Name of project : Code of S/C : Name of TSO : Date of form preparation : 1. Location: where is the structure located within the Sangkat/Commune ? 2. Provide the coordinates of GPS. X of GPS Y of GPS 3. Fill type 3 Source: borrow pit Source distance from structure (km) 4. Sands Source: borrow pit or stream bed. Source distance from structure (km) 5. Gravel Source: borrow pit or stream bed. Remark: for concrete work, the gravel from stream bed is not permitted. Source distance from structure (km) 6. Stone Source: quarry or stream bed. Type of stone: Hard metamorphic rock (granite, basalt, etc), limestone and sandstone. Source type of stone distance from structure (km) 7. Water supply for earthwork Source distance from structure (km) 8. Foundation soils: what kind of soils is the structure founded on? If “Others”, fill the questions following. Very easily eroded soil Normal clay Sandy soil Gravel Earth with big stone in it Others 9. Other types of soils: mention them. 10. Foundation strength of DCP (mm/blow) and location of each test. * Location: stream bed road centre line, stream bed up stream, stream bed downstream, left bank abutment, right bank abutment or others. DCP (mm/blow) location 11. what is the 20 percentile DCP * You can calculate this value with Applet T11 12. Crossing structure: is there an existing crossing structure ? * if “Yes”, answer the following questions, if “Not”, go to “Flow capacity” YesStudy and Design Guidelines I-172
    • Annex 1: Technical Forms No 13. Road classification: District to district District to commune Commune to commune Commune to village Village to village Farm acces 14. What is the largest vehicle that uses the earthwork? Passenger car People walking Motorcycle Motor-remorque Bicycle Animal cart Light vehicle/van Koyun Medium truck (6 tyres) Heavy truck (6 tyres) Bus (>4 tyres) Mini-bus (4 tyres). 15. Flow capacity: what is the design flow capacity (can be from T22), (m3/s)? * Calculated from canal capacity. You can skip this question for spillways or river intake. Generally, if the design structure is passed by the irrigation flow and drainage flow, you must design the structure the drainage flow, because its value is always higher. 16. What is the flow capacity at the structure (m3/s)? * Calculated from canal capacity. You can copy skip question for spillways or river intake. Generally, if the design structure is passed by the irrigation flow and drainage flow, you must design the structure the drainage flow, because its value is always higher. 17. Can this flow capacity be higher than design one? If “Can”, answer the following questions, if “Can not” skip them. Can Can not 18. Describe the circumstance and consequence for the structure also what provision will be provided to survive an extreme flow? Using the design guidance spillways is sized for 1 in 50 year flow into the reservoir;Study and Design Guidelines I-173
    • Annex 1: Technical Forms the reservoir freeboard allows some of the flood to stay temporarily in the reservoir until it call all pass over the spillways. A concrete stilling basin and erosion protection will be provided downstream. 19. Did you use “Applet” to determine the design flow and length of structure? (Spillway and diversion weirs) * if you don’t design the spillway or river intake, skip them. Yes No 20. Spillway and diversion weirs: is the structure for reservoir or river intake? Reservoir River intake 21. What is the design flow for spillway or river intake (m3/s) ? * Copy from Applet T23, worksheet GTFM: C32. 22. What is the maximum safe water level at the upstream of structure? ( higher than this level, it can be flooded, overtopped). * Copy from Applet T23, worksheet GTFP: C33. 23. What is the proposed weirs crest level? ( it is a full water level of a reservoir or river level intaking to the system). * Copy from Applet T23, worksheet GTFM:C34. 24. Required weirs length (m): * Copy from Applet T23, worksheet GTFM:C35. 25. Pumping capacity: provide the pumping capacity (m3/s). * Answer if there is a pumping, see the irrigation project form T22. 26. Responsibility for operation and maintenance: is there a Farmer Water User Comity (FWUC) or similar group of people who are willing to take responsibility to operate and maintain the structure? Yes No 27. Who will operate and maintain the irrigation structure? Commune council 28. Remark: Don’t forget to upload “Applet” that you used in your calculation.Study and Design Guidelines I-174
    • Annex 1: Technical FormsTechnical Form T31 – Water SupplyForm T31 Water supply Province : District : S/C: Name of project : Code of S/C : Name of TSO : Date of form preparation : 1. Location: where is the water supply located within the Sangkat/Commune? 2. Provide the coordinates of GPS. X of GPS Y of GPS 3. Number of proposed output: provide the number of proposed output? * Remark: Form T31 is only for one water supply output, it mean that, if you have many exactly the same output and same output data, you just make one output, answer just one technical form and provide the number of those output. 4. Purpose of water supply: for what purpose is the water supply used? If the “Village”, answer the question 5, if “School” or “Health center”, answer question 6. Village School Health centre 5. Information about number of users: how many people use the water supply? In which village do they live? * Totalize the numbers above and write it down in the last row. Name of village people in village number of family using the water supply 6. Number of supplier in school and health post * If you chose “School” in the answer above, write down only the number of rooms and number of students. If you choose “Health post” write down only the number of users in the health center. Number of school rooms number of students or health post 7. Maintenance: Who will maintain the water supply? 8. Existing water supply: how many families use the existing water supply? * if the existing water supply is for school, write down only “use for school”. 9. Have the families who will use the supply agreed to form a Water Supply Committee? Yes No 10. Where does the domestic water used by these people come from now? * Source: watercourse, natural pond, dug pond, rain water harvesting, spring, village well, household will, water-point piped. Totalize the number of users, and then write it down in the last row. Source number of users distance to the centre of village (km) 11. Information about proposed facility: Who owns the land where the new facility will be constructed? * if the land is in private ownership, answer the question 12. CommunityStudy and Design Guidelines I-175
    • Annex 1: Technical Forms Private 12. Does the landowner agree to construction and unrestricted use of the facility? Yes No 13. Does the location of the facility ever flood? * if “Yes”, answer the questions 14 and 15. Yes No 14. What is the depth of flooding in meters ? 15. What type of flooding? Seasonal and prolonged flooding from high river levels Short periods of flooding following heavy rain 16. Existing well: what type of well are in the village or near vicinity? * You should choose the existing well which is closest to the new well Dug well Drilled well Mixed well 17. Provide the coordinates of GPS Type of well X of GPS Y of GPS 18. What is the distance (closest) from the existing well to the proposed well (km)? 19. Who owns this existing well? 20. Is the existing well used for domestic water or farming? Domestic water Framing 21. How old is the existing well? 22. How deep is the existing well? 23. What is the static water level in the dry seasons? 24. What is the static water level in the wet seasons? 2 25. How many families use the sell? 26. Does the existing well have enough water all year? Enough Not enough 27. What does water from the well taste like? Note taste Salty Bitter 28. What is the color of the water in the existing well? ClearStudy and Design Guidelines I-176
    • Annex 1: Technical Forms Gray Yellow Brown 29. Does it smell? Yes No 30. Has the water from the existing well ever been tested for arsenic? Yes, ever No, never 31. What kind of soil or rock is the well sunk in? From depth (m) to depth (m) kind of soil or rock 32. How do you know about the information on the soil or rock? 33. How are the other well ? No information on other wells To many well to list Other wells similar 34. Proposed well: name of proposed well 35. What kinds of soil or rock will the well sunk in? From depth (m) to depth (m), kind of soil or rock. From depth (m) to depth (m) kind of soil or rock 36. How deep is the water bearing soil or rock (the aquifer)? 37. What is the depth of proposed well? 38. What is the static water level in the dry season (depth below ground in metres)? 39. What is the estimated dynamic water level in the dry season (drawn down by pumping) (depth below ground in metres)? 40. How do you know the information on the proposed well? 41. Where will wastewater from the new well drain to? If “Other”, answer the question 43. Soak away Watercourse Pond Other 42. If “Other”, list your answers. 43. Is there anything close to the well that could cause contamination of the well? * If “Other”, answer the question 45. None Latrine Animal pens CmeteryStudy and Design Guidelines I-177
    • Annex 1: Technical Forms Chemical store Fuel store Other 44. If other, list your answers. 45. if a potential cause of contamination is identified, write it down. Consider another well location a safe distance from contamination source or explain in the box below what measures will be taken to prevent contamination. 46. Suitable pump for well VN N°6 pump, dynamic water level d 6m (suction pump) Afridev Tara, dynamic water level 0 to 25m (force mode) Seek specialist advice, dynamic water level > 50m None 47. Proposed pond: what kind of soil or rock will the pond be dug in? From depth (m) to depth (m) kind of soil or rock 48. Are there any wells, natural or dug ponds nearby? If “Yes”, answer the question 49. 49. If “Yes”, what is the standing water level in metres below ground level? Depth in dry season (m) depth in wet season (m) 50. Where will the water to fill the pond come from? If the answer is rainwater harvesting, answer the question 52, if “Other”, answer the question 53. Rainfall directly into pond Rainwater harvesting High groundwater levels Other 51. If “rainwater harvesting”, over what area will the water be harvested? 52. If “Other”, list your answer.Study and Design Guidelines I-178
    • Annex 1: Technical FormsTechnical Form T41 – Education FacilityForm T41 Education Province : District : S/C: Name of project : Code of S/C : Name of TSO : Date of form preparation : 1. Location: where is the education facility located within the Sangkat/Commune? Describe the location of education facility. 2. Provide the coordinates of GPS * Coordinate of school location X of GPS Y of GPS 3. List the number and length of the proposed facility. * Rooms of the new school, list the number of room. Furniture: list the number of set of chairs and tables. Primary school, training room, library, school dormitory, school yard, list the number of place. List the length of school wall and school fence in meters. 4. Information about education requirement: (about students) How many students will use the school and which village will they come from? Name of village Number of children go to distance from village to the school school in kilometers 5. Total number of children goes to the school. 6. About the number of classroom. How many classrooms on the site now? 7. About the number of teachers teachers provided by the teachers will be hired for Total number of teachers education department the school available 8. About the school management: is there a school parent’ committee? Yes No 9. Physical characteristics of the site: does the site ever flood in the wet season? * if “Ever”, answer the two following questions. Ever Never 10. What is the maximum depth of flooding in meters? 11. What type of flooding? Seasonal flooding and prolonged by the high river level Short periods of flooding following heavy rain 12. Is the site free of mines and UXO? * if “Yes”, answer the following question. Yes No 13. Does land title exist for the site? * If “Yes”, answer the following questions. Yes NoStudy and Design Guidelines I-179
    • Annex 1: Technical Forms 14. What stage is the documentation (district, province…)? 15. Is the site presently occupied? * If “Yes”, answer the following questions Yes No 16. Whom or what? (E.g. building, rice field and will compensation be expected/demanded?) 17. Is the site presently walled or fenced? Yes No 18. Will land fill or embankments be needed to protect against flooding? * If “Yes”, answer the question 19 Yes No 19. If “Yes”, describe it. 20. Is there enough space for students to play sports? Yes No 21. Is there enough space to build more classrooms in the future? Yes No 22. What is the water supply at the site? * If “Pond” or “Pumping well”, answer the following question None Pond Pumping well Piped supply from off site 23. Write down the dry season water level below ground (m) 24. How many existing latrines at the sites? 25. Foundation soils: (for school building construction, school fence and walls) What kind of soil will the school be constructed on? * Type of soil: gravel, silty sand, micaceous sand, lateritic sand, clayey sand, loams, organic clays, lateritic clays, dandy, silty or clayey peats. Number X of Y of Depth (m) Type of group of soil of trial pit GPS GPS soil 26. DCP test (mm/blow) DCP (mm/blow) X of GPS Y of GPS 27. 20 percentile of DCP (mm/blow)Study and Design Guidelines I-180
    • Annex 1: Technical FormsTechnical Form T51 – HealthForm T51 Health Province : District : S/C: Name of project : Code of S/C : Name of TSO : Date of form preparation : 1. Location: where is the health facility located within the Sangkat/Commune? Next to the commune centre, in Phsar Leu market 2. Provide the coordinates of GPS * First line is the starting point; last line is the ending point X of GPS Y of GPS 3. List the number and length of output chosen. * Fence in meter, and other output in number. 4. Information about health facility: how many people will use the health facility and which villages will they come from? * Copy the total number of people from the Project Information Form. 5. How many trained staff will be provided by the health department? 6. How many staff will be hired for the health facility? 7. What is the total number of staff available? * totalize both numbers above. 8. Physical characteristics of the site: does the site ever flood in the wet season? * if “Ever”, answer the following questions. Ever Never 9. If “Ever”, what is the maximum depth of flooding in meters? 10. If “Ever”, what type of flooding? Seasonal and prolonged flooding from high river levels. Short periods of flooding following heavy rain. 11. Is the site free of mines and UXO? Yes No 12. Does land title exist for the site? If yes, at what stage is the documentation (district, province…) 13. Is the site presently occupied? If yes, list them. * e.g. building, rice field… will compensation be expected/demanded? 14. Is the site presently walled or fenced? Yes No 15. Will land fill or embankments be needed to protect against flooding? Yes No 16. What is the water supply at the site? None PondStudy and Design Guidelines I-181
    • Annex 1: Technical Forms Pumping well Piped supply from off site 17. How many existing latrines at the site? 18. Foundation soils: what kind of soil will the health facility be constructed on? * Kind of soil: gravel, silty sand, micaceous sand, lateritic sand, clayey sand, loams, clayey silts, organic silts, micaceous silts, sandy clays, silty clays, organic clays, sandy; silty or clayey peats. Number X of Y of Depth (m) Type of group of soil of trial pit GPS GPS soil 19. Foundation strength DCP Test (mm/blow). DCP (mm/blow) X of GPS Y of GPS 20. 20 percentile of DCP (mm/blow) ?Study and Design Guidelines I-182
    • Annex 1: Technical FormsTechnical Form T101 – SanitationForm T101 Sanitation and drainage Province : District : S/C: Name of project : Code of S/C : Name of TSO : Date of form preparation : 1. Location: where is the sanitation and drainage located within the Sangkat/commune? Describe the location 2. Provide de coordinate of GPS. * if it is a point, fill only the first row. First row is the starting point and the second row is the ending point. X of GPS Y of GPS 3. Description of requirements: give a brief description about the project. 4. List the number or length of the proposed outputs. * provide the number for the latrines and length for the drain. Output Number or length 5. Drainage capacity: give drain a name; area of land drained, flow rate (m3/s/ha), flow capacity and external catchment. * in peri-urban or village can allow for 50m wide strip from road centerline for drains each side of road. Recommended flow rate is 3.5l/s/ha, but you choose another value. The required flow capacity of drain = flow rate x drained area. Will the drain collect water from catchments beyond the drain, e.g. a stream flow into the head of the drain from a small catchment or drain system? Write down “Collect” or “Does not collect”. Name of drain Drained area Flow rate Flow capacity External (ha) (l/s.ha) (l/s) catchment 6. Remark * if you chose “Collect”, answer the two following questions. 7. Describe briefly how the extra catchment affects the requirements, e.g. it may only affect a drain one side of the road. Name of drain Description 8. Give a name of drain collecting water from external catchment, area of external catchment, flow rate (l/s/ha) and extra flow capacity. * if catchment area > 1.0Km2, flow from this catchment will be too big for a culvert or a drain, so let think about the flow conveyance or a special advice. * Recommended drain flow capacity is 3.5l/s.ha, but you can choose another one. * flow capacity extra = catchment area (ha) x flow rate (l/s.ha). Name of drain External catchment Flow rate (l/s.ha) Extra flow capacity area (ha) (l/s) 9. Calculate the total design flow capacity for box culvert (l/s). * Total design flow capacity = drain flow capacity (l/s) + extra flow capacity of external catchment (l/s) Name of drain Design flow capacity (l/s) 10. Design of box drain: remark You must use “Applet Form T101 Drain” to determine the design flow, channel bed level, bottom width and channel velocity. 11. Result of the design of box drain and drain from Applet T101. * Skip it if you don’t design the box drain. Copy the answer from Applet T101 that you used to calculate.Study and Design Guidelines I-183
    • Annex 1: Technical Forms Name of drain Required flow Bed depth (m) Width of box Design capacity (l/s) drain (m) velocity (m/s) 12. Design of pipe drain: remark Use “Applet Pipe Chart” to determine the diameter of pipe drain. 13. Result of the design of pipe drain from Applet Pipe Chart * Skip it if you don’t design the pipe drain. * calculate the flow capacity, see the suitable pipe and copy the answer from Applet Pipe Chart that you used. Name Required Pipe Pipe Efficient Type Minimum Chosen of drain flow drain length hydraulic of pipe diameter diameter capacity depth (m) gradient (m) (m) (l/s) (m) 14. Remark Upload the Applets you’ve used to get the result as above.Study and Design Guidelines I-184