Hunda PROJECT-II.docx

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PROJECT-II ON SUGARCANE IRRIGATION SYSTEM AT TANA BELES SUGAR
DEVELOPMENT PROJECT
Arba Minch University
Institute of Technology
School of Graduate Studies
Department of Water Resources and Irrigation Engineering
Prepared By:
HUNDA TOLINA
ID No: PSAWTI014/11
Project-I (IDES-625)
TO: Dr. ENG ABDELLA KAMAL
Junu, 2022
Arba Minch,
Ethiopia

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I will always be remembering his words “Don’t worry, you can do it” for my entire life.
ACKNOWLEDGEMENT
First of all, I must thank the Almighty God who helped me starting from the earlier to the end of this journey.
The writer desires to thank, the sponsor organization Ethiopia Sugar Corporation, and Tana Bales sugar
project for the opportunity given to him to undertake this MSc. program and financial encouragement for
the academic cost.
I would like to express his genuine thanks to his advisor Dr. Abdella Kamil for his excellent guidance,
kind, tolerance, continual support, careful attention, critical comment and continual attendant provided by
him with an excellent initiation atmosphere for conducting research.
Finally, I would like to extend my gratefulness to Pawi Metrology Branch for providing me weather data.
(Hunda Tolina Jaleta)

Project-II On sugarcane irrigation system: at Tana Bales sugar project
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Table of Contents
ACKNOWLEDGEMENT..................................................................................................................................i
Abstract..........................................................................................................................................................iv
1. INTRODUCTION.....................................................................................................................................1
1.1. Aims and Objectives...................................................................................................................... 3
2. DESCRIPTION AND LOCATION OFTHE PROJECT............................................................................................4
2.1 Location............................................................................................................................................. 4
2.2 Climate .............................................................................................................................................. 6
2.3 Command Area................................................................................................................................... 6
3. Main problems of Irrigation System............................................................................................................8
3.1. Problemidentification................................................................................................................... 8
3.2.1 Infield sprinkler of TBDSP has a lot of problems; some of these are listed
below 10
3.2.2 The highest priorities of problems and their causes:...................... 11
4. METHODOLOGY ...................................................................................................................................... 12
4.1 Assessment of the existing irrigation practices andits problem ............................................................12
4.2 Data Collected Methods.....................................................................................................................12
4.2.1 Primary Data Collected....................................................................................................................12
4.2.1.1 Equipment used ...........................................................................................................................12
4.2.1.2 Soil Data......................................................................................................................................12
4.2.1.3 Silt measurement:........................................................................................................................13
4.2.1.4 Pressure Measurement.................................................................................................................13
4.2.2 Secondary Data collected ................................................................................................................14
4.2.2.1 Crop Root depth and Crop coefficient............................................................................................14
4.2.2.2 Climatic Data used........................................................................................................................14
5. SOLUTION FOR TANA BALES IRRIGATION PROBLEMS................................................................................. 15
1. WEIR, HEAD REGULATOR AND UNDER SLUICE......................................................................15
Solution for problem number1: Installing Jeep crane to clean under sluice
frequently 16
3.2 MAIN CANAL 18
Solution for Main canal problem : siltation..................................... 18
Using long reach Excavator cleaning canal:...................................... 20
Solution frominfield problems:....................................................................................................................... 25
Surface irrigation problems......................................................................................................................25
SPRINKLER IRRIGATIONS PROBLEM:.................................................. 28
Calculating Irrigation Schedule:................................................................................................................28
Data used...............................................................................................................................................29
ADDITIONAL MATERIAL FOR THIS ADJUSTMENET............................................................................................. 39
6. CONCLUSIONS AND RECOMMENDATIONS...................................................................................... 41
APPENDIX ................................................................................................................................................... 42
Bibliography................................................................................................................................................... 45

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Lists of figures
Figure 1 : Location map of Project Area. Source: Feasibility and Design Study of TBISDP (2013) ...................... 4
Figure 2 : Upper Ayma Command Area Elevation Map. Source: Feasibility and Design Study of TBISDP (2013). 5
Figure 3 : Upper Beles Command Area Elevation Map. Source: Feasibility and Design Study of TBISDP (2013).. 6
Figure 4: ogee type weir with problem of concrete grade.................................................................................... 9
Figure 5: sprinkler irrigation with low pressure.......................................................Error! Bookmark not defined.
Figure 6: poor field management ...........................................................................Error! Bookmark not defined.
Figure 7: before and after maintenance of wear...............................................................................................15
Figure 9 : Stainless steel........................................................................................Error! Bookmark not defined.
Figure 10 : Jib crane for head work..................................................................................................................18
Figure 11: Long reach excavator......................................................................................................................22
Figure 12: Inclination of trash racks .................................................................................................................24
Figure 13 : Dimension of our trash rack............................................................................................................25
Lists of Tables
Table 1: Slope classes of the irrigation command area........................................................................................ 7
Table 2: Beles Soil Area Coverage.................................................................................................................... 7
Table 3: Time schedule of canal maintenance.........................................................Error! Bookmark not defined.
Table 4: Description of sugarcane (KC) ...........................................................................................................30
Table 5: Net and gross depth of application ......................................................................................................31
Table 6: ETo of Tana bales...............................................................................................................................32
Table 7 : Effective Rainfall of pawi station........................................................................................................33
Table 8: soil moisture content and available water content...............................................................................34
Table 9 : CWR representation..........................................................................................................................35
Table 10: irrigation scheduling.........................................................................................................................37
Table 11: output data of tana bales .................................................................................................................38
Table 12 : recommended sprinkler set time and irrigation interval ....................................................................39
Graph 1: Graph representation of ETO.............................................................................................................32
Graph 2: Description of sugarcane coefficient ..................................................................................................34
Graph 3: Graphical representation of irrigation required...................................................................................35
Graph 4: Graph Representation of irrigation scheduling....................................................................................37

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Abstract
This paper focuses on the possible solutions to the challenges of irrigation water pricing for Tana Bales
sugar project in Amhara and benishangul Region. The current budget of Tana bales is necessary to reform
as they could not cover the operation and maintenance cost of the overall system. Rope system for gate
operation is on closing the gate of both under sluice and head regulator because of water pressure under
gate system. One of the mostimportantand at the same time mostdifficultconditionstoensure inthe
constructionof an irrigationcanal,isthat nosiltingshall take place init.The originof the increasedsediment
transportintocanal isfrom erosiononlandor activitiesinthe water. For this problem solution is only
changing rope system to stainless steel handling. This problem may solve with the following operation:
Preparing Cleaning schedule, Creating Road one side of the canal and installing good trash rack. One
complex and big problems in our canal are water loss and Geo membrane damages. To solve this problem
it need huge amount of cost and machinery. Only permanent solution is changing geo membrane with
masonry canal. The other problem in sprinkler irrigation is irrigation interval or irrigation scheduling: to
get good productivity we have to solve this problem. To solve the problem of irrigation interval I use
CROPWAT

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1. INTRODUCTION
Sugar cane agriculture is the one share of Ethiopian agricultural economy. As a result, the Ethiopian Sugar
Corporation was established by Government proclamation in the 2nd day of December 2010 to undertake the
responsibility of the entire Ethiopian Sugar sector development. It plays a leadership role in the development,
management and marketing of sugar and its byproducts. Following its establishment the Sugar Corporation has
launched short and long term capacity building programs targeted to support the large scale sugar development
in the country. Capacity building shall focus on Research and Human resource training in sugarcane
agriculture, Sugar industry and support services related to financial management. (ESC, 2012)
This paper focuses on the possible solutions to the challenges of irrigation water pricing for Tana Bales
sugar project in Amhara and benishangul Region. The current budget of Tana bales is necessary to reform as
they could not cover the operation and maintenance cost of the overall system
The Federal Democratic Republic of Ethiopia has launched sugar development program to undertake new
and Expansion projects across the country with a clear objective of boosting sugar production to satisfy the
domestic sugar demand as well as for any possible export.
Accordingly Tana Beles Integrated Sugar Development Project is the one among the new sugar development
projects. According to the government plan, the development of massive irrigation projects for sugar
production in different parts of the country is involved.
The Ethiopian Sugar Corporation with an objective of raising the sugar production of the country planned to
develop about 250,000hectare of land for cane production in the coming 10 years. One of the potential sites
selected for cane production is Upper Beles Right command and Upper Ayma command. Tana Beles Integrated
Sugar development Project is proposed on these commands. The project was initially started by Amhara
National Regional State and later transferred to the Sugar Corporation. The project site is located in the Amhara
National Regional State and BenishangulGumuz National Regional State. The objective for carrying out the
studies and detail designs, is to prepare a feasibility and detail design reports for establishing three sugar
factories having cane crushing capacity of 10,000 TCD (revised to 12000 TCD)each, having annual production
capacity of 242000 tons of sugar with ethanol and co-generation facilities. Hydrological analysis and
investigation is an essential component of water resources projects to estimate key design parameters required
for various hydraulic structures. The project under this study is of Sugar Cane development by diverting the
available water in Beles catchment and additional release of water through the Beles hydropower turbine which
will transfer more than 77 m³/s of water from the Lake Tana to Beles head water system
The project activity will be started on the south from the weir site after 11.9km following the main canal for
Upper Beles and south eastern tip of Upper Ayma.Finally, 37,207ha and 35,737ha were allocated at Upper

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Beles and Ayma respectively, totally 72,944ha of land were demarcated for TanaBeles Integrated Sugar
Development Project. The basalt covered most of the project area and is composed of slightly weathered to
massive basalt. The unit has degassing cavities and vesicles filled by secondary minerals. The rock around the
head work and main canal show different degree of weathering. The Phorpiritic basalt is highly decayed as
observed on top abutment excavations and main canal route. The same is true for the dolerite and basaltic
dykes. But there are exceptions for basaltic dykes that there are fresh and sound outcrops except some
fracturing effects
The project will be supplied water diverted from the Beles River by a diversion head works comprising of a
diversion weir, under sluices and a head regulator at the right bank of the river. The head works is located at
about 28km from Fendika town. The Beles River is supplied by natural runoff from the upstream catchment
and more recently by the TanaBeles hydropower scheme which uses water from Lake Tana and discharges into
the Beles River upstream of the diversion works. Pressure irrigation has been considered in the large area for
the large scale commercial sugar cane estate where there is sufficient head from the main canals to the
irrigation command area by gravity, without need for pumping except for areas around 2000ha it requires pump
to create head. Besides, surface irrigation for some area (about 1890 ha) in Upper Beles Command has also
been considered. Pressure irrigation has some advantages over surface irrigation such as higher application
efficiencies and avoidance of terracing of land steeper than 3% slope. The land development for pressure
irrigation would also be minimal. Main Canal is approximately 30 Km and ends near Fendika Town from
where Trunk mains for Sprinkler Irrigation for Phase I & Phase II of Upper Beles and Upper Ayma left side
command areas, take off. 40% of its length lies in rocky strata, 8.5% in filling and rest traverses through earth
in cutting constituting mostly of vertisol type of soil. The main canal is proposed to be lined, with concrete bed
and masonry sides with vertical water face, where the rock is encountered and in the filled reaches. Where the
canal is in cutting in soils, trapezoidal sections with 1.2 mm thick HDPE film as geo membrane have been
adopted. The Primary canals will also be lined with 1.2 mm thick HDPE film and masonry for gentle slope
portion, reinforced concrete where the canal section is chute while the secondary canal is pvc pipe. The Upper
Ayma command area will be supplied water through an off take structure at right bank of the main canal at
chainage 26.56 Km. Cross regulators have been provided for every primary, secondary canals and escape
channels. Gated regulators have been provided for cross regulators and head regulators of the off- taking
canals. The main canal being a contour canal crosses large number of drainages. For crossing these drainages
32 number of cross drainage structures have been provided. To prevent clogging of sprinklers, a sedimentation
chamber has been provided at 25.1Km, so that the sediment particles of size greater than 0.3 mm are settled and
ejected. An intake structure has been provided at Km 30 of the main canal (Tail end) for the trunk mains
supplying water for Upper Beles phase1, phases 2 sprinkler irrigation and Upper Ayma left side command
areas. An escape channel and chute spillway have been provided at the intake for escaping the surplus water

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and to off take water for Ayma left side command respectively. The ladders/ stairs for access inside the main
canal to facilitate inspection and maintenance of main canal have also been proposed. Social structures viz.
bridges, foot bridges and cattle troughs have also been proposed.
Most of the study area has well to moderately well drain soils. However, most of the command’s black clay
soils (vertisols) are imperfectly to poorly drained, mainly due to the high clay content and flat to almost flat
topographic positions. The majority of the irrigation command area at Upper Ayma and Beles are waterlogged
throughout the rainy season from the larger area coverage of vertisols and other soil units both due to external
(surface) and internal drainage problems and remained uncultivated at present. Especially for Vertisols, a
proper drainage ditch network will need careful design and will be integral to the project with priority to
remove surface water following rainfall and from excessive irrigation. The non-Vertisols soils are generally
well or moderately well drained. The main need is to ensure that excess rainfall and irrigation can be led off the
land safely by careful contouring and surface drainage to existing streams. For all soil types, because most of
the land is sloping, the drainage network must be carefully aligned to contours to prevent the ditches
themselves getting eroded. All weather roads, Haulage roads and farm roads have been proposed for easy
transportation and efficient haulage of sugarcane from farms to the factory. Operation of canals and sprinkler
systems are relatively simple provided a few checks and operating rules are followed and due attention is given
to the regular maintenance and care of the system. These operation rules and maintenance and care are also
discussed in a separate section
The project has started seed and commercial cane plantation activities in 2012 G.C using irrigation water
from Beles River with the aid of Diversion Weir using both surface and pressurized irrigation methods.
Currently the project has covered a total of around 12,000 hectare of cane plantation area. The sprinkler
irrigation system is a gravity hose move sprinkler irrigation system. The whole sprinkler irrigation system
supplied water from the main canal with the aid of gravity off take pipe and deliver water to the fields through a
network of supply mains, Branch mains, Sub Mains, Mani Folds, Laterals, Drag Hoses and Sprinklers.
1.1. Aimsand Objectives
 The main objective of this Project was To suggest and develop the best design and management
solutions for the problems identified in project I
Objective of project-2
 To develop irrigation scheduling of the existing sprinkler system
 To solve canal siltation problem

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2. DESCRIPTION ANDLOCATION OFTHE PROJECT
2.1 Location
Tana Beles Integrated Sugar Development Project is located near Fandika Town, capital of JawiWoreda,
which is 150km from capital city of Awi zone, Enjibara, 270km from capital city of Amhara National Regional
State Bahirdar.TanaBeles Integrated Sugar Development Project found in the western periphery of Amhara
National Regional State,and also found BenishangulGumuz National Regional State, 60km from capital city
ofmetekel zone GilgelBeles and 300km from capital city of BenishangulGumuz National Regional State Asosa.
The project activity started on the south from the weir site after 11.9km following the main canal for Upper
Beles and south eastern tip of Upper Ayma. The total proposed irrigated area of about 50,000ha (Gross) for two
sugar estates in Upper Beles and Upper Ayma, has to be supplied water by the main canal running along higher
ground along the northwest side of the project area.The project has been supplied water diverted from the Beles
River by a diversion head works comprising of a diversion weir, under sluices and a head regulator at the right
bank of the river. The head works is located at about 28km from Fendika town. The Beles River is supplied by
natural runoff from the upstream catchment and more recently by the TanaBeles hydropowerscheme which
uses water from Lake Tana and discharges into the Beles River upstream of the diversion works,hydro electric
power fuond in West Gojam zone, North AcheferWoreda, kunzila town.
The study area has low to medium relief differences with an altitude range of 806 to 1242 meters above sea
level. The Upper Beles (Right side) irrigation command area has an altitude ranged from 962 to 1,242 m.a.s.l,
which is characterized by flat topography (plain land), whereas the Upper Aymairrigation command area is
between 806 to 1154 m.a.s.l, mainly characterized by undulating topography. The general location map of the
project area is shown in figure below
Figure 1 : Location map of Project Area. Source: Feasibility and Design Study of TBISDP (2013)

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The Upper Ayma irrigation command area is situated on the right and left banks of Ayma River Gorge,
originated from the head of Fendica Town. The project area is geographically located between 0198473m to
0225347m East and 1277734m to 1308983m North UTM stretch from Jawi capital town Fendika to Quarit
village. The proposed suitable land for irrigated and mechanized sugarcane production is found at lower
elevation of the surrounding ridges defined by natural boundaries, being bounded to the south by the slopes of
Belaya Mountain and to the west by the rising land of the Bakussa Escarpment; to the north and east by
confined ridges and uplands associated with AboyGara Mountain and Fendica Ridges, respectively. Ayma
River flows through the heart of the study area towards at northwest to QuaraWoreda. The actual surveyed area
covers some area of about 57,614 ha in the left and right sides of Ayma River, with a maximum width of 16
km, east to west and length of 34 km south to north. It lay between an altitude of about 806 m.a.s.l at the outlet
of Ayma River and 1154 m.a.s.l at the southern tip of the study area and lower point of Fendica Ridge. Ayma
area is located at a distance of 5km from Upper Belesboundary in the northwest direction. The location map of
the Upper Ayma irrigation command area of the project is shown in Figure 2:
Figure 2 : Upper Ayma Command Area Elevation Map. Source: Feasibility and Design Study of TBISDP
(2013)

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The gross command area covers some area of about 38,334ha of land found at the right sides of EnatBeles
River and left from the proposed main canal, with a maximum width of 13 km, east to west and length of 68
km south to north. The area stretched from southwest of the weir site following right sides of BelesRiver.
Figure 3 : Upper Beles Command Area Elevation Map. Source: Feasibility and Design Study of TBISDP
(2013)
2.2 Climate
The project area is located close to Pawe station, 30km from our project and can be characterized as warm
humid climate with mean annual humidity reaching to 80 % and the maximum temperature fluctuating between
390C in April and 270C in July, while the minimum temperature variation is bounded between 120C
(December) and 190C (July).
Over all, the project area is considered to be humid with relative humidity ranging between 66 and 92% with
more than 50% the year reaching about 80%. The actual sunshine hour also varies between 7 and 10 hours per
day during most of the year except the rainy seasons of July- September where this decreases to less than 7
hours a day. Particularly, the decrease reaches to less than 5 hours a day during July and August. Source: The
mean annual rainfall around the irrigation scheme is represented byPawi station with mean annual rainfall of
1576 mm (from 1986-2006) with the low variability during the wet season (CV less than 0.3). (Pawi
Agriculture wheather data station, 2009)
2.3 Command Area
The command area is bounded by the main canal to the northwest. The alignment of the canal is defined by
the need to be able to command the right bank and Upper Ayma irrigation area. The main canal therefore
follows the high ground all the way around the command area and defines the project area except where the
main canal goes south of Fendika which means a very small part of the project area is to the north of this canal.
Slope is most important site characteristics as it influences the suitability to irrigation and methods of irrigation
and type and kinds of farm operations and machineries. In this regard, the majority of the irrigation command
area is flat and gently sloping, still other slope classes also constitute limited proportions. (design, 2013).

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NO Slope class Area (ha) Cover (%)
1 Flat (0-2%) 36250 37.78
2 Gently sloping (2-5%) 42559 44.36
3 Undulating to sloping (5-8%) 12494 13.02
4 Rolling (8-12%) 3158 3.29
5 Rolling to hilly (12-16%) 925 0.96
6 Hilly (> 16%) 561 0.59
Table 1: Slope classes of the irrigation command area.
Type of soil Area coverage in percentage Area coverage in ha
Verti sols >50% >37000
Luvisols 9% 6750
Nitosols 5% 3500
Cambisols 5% 3500
Leptosols 6% 4500
Table 2: Beles Soil Area Coverage
Source: (Feasibility and Design Study of TBISDP , 2013)
Verti sols:-cover more than 50% of the command area, heavy clay soil which is deep swell and shrink.
Luvisols: -covers 9% of the gross command area, which is deep reddish clay soils in which silicate clay
are transported form high nutrient content and good drainage. Nitosols: covers 5% the gross command
area, which is deep reddish clay soils more than 30% clay fertile soil.
Cambisols:-covers 5% the gross command area, which is a Brownish weakly developed soil and it is
unsuitable for sugar cane. Leptosols: - covers 6% the gross command area, Very shallow and very stony
soils (unsuitable for sugar cane production).

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3. Main problems ofIrrigationSystem
3.1. Problemidentification
The construction works of the project comprises head work, main canal, cross drainage structures, and
command area development in 14,200 ha; Nursery site expansion and catchment drainage construction. In the
reporting month, the Contractor /AWWCE/ is working on the construction of escape canal at chainage 30+000
of main canal and Ayma left primary canal. In command area development the contractor AWWCE/ has been
working in the construction of secondary canals 7, 8, trunk main-3, phase 3 of trunk main-2 and Trunk main-1.
The construction of farm access road of secondary canals 5 & 6 construction has been in progress by AWWCE.
Amhara Road Works Enterprise/ARWE/ is the other contractor for the construction of farm access roads in
trunk main 1, 2 and 3. Even though the achievement has been delayed compared to the Client target due to
shortage of machineries in completing the main canal, the construction activities of the head work and the main
canal up to 30 km have been completed except canal empting structures at chainage 30+000, gate installation
for cross head regulators at chainages (15+000, 22+400, 26+500), installation of gate for canal empting
structures at chainage 16+500 and 30+000.
There are a lot of problems in case of Tana bales irrigation system, and we will see in detail below:
3.2.1 Weir, head regulatorand undersluice
Basically under sluice were provided to:-
 Scour (remove) away the silt deposited in front of head regulator. Now a day its solved
 Passes small floods of design flood during rainy season to downstream.
Under sluice provided to control water during irrigation period and to flash out silt and water during rainy
season. It had three openings with sizes of 3.30 by 2.70 meter.
The weir has one big problem, it is constructed below its concrete grade i.e. the recommended criteria is C-
40 but for this case contractor only use C- 35. The economic life span of this weir 30 years and above, but now
a day the weir fails with in only five years duration and it need maintenance activities. Weir and under sluice is
divided by division wall, and this wall also constructed below its concrete grade.

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Figure 4: ogee type weir with problem of concrete grade
The main under sluice gate problem on gates and its fittings mentioned as follow:
I. Problem of painting antirust (solved)
II. Problem of clump cover of rope(solved)
III. For this under sluice there is no Jeep Crean for cleaning the gate
Below
its
grade

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3.1.2 Maincanal
Canal is a conveyance structure which is constructed for different purpose using different materials, such as
earthen material, masonry and concrete. It has different shape and size based on the discharge of flow, physical
geography feature and economical consideration. Canal in TBISDP is used as irrigation purpose which are
planned to irrigate around 60,000ha of land & designed for discharge 60m3/sec at full capacity level.
The problems of TBSDP Main canal are mentioned bellow:
1. Siltation problem
3.2.1 Infield sprinkler of TBDSP has a lot of problems; some of these are listed below
Tana Beles Sugar Development Project, face a problem of appropriate in field irrigation water application
practices; some of these problems are listed below
 applying water at uniform level irrespective of the soil, growth stage, and growing month, It is not
considered the system actual water application and crop water requirement because of no water measurement
device
 Also there is problem of non-uniformity of water application, Poor system operation, care and
maintenance
 Due to these problems, most field cane areas were under the crop need (wilting, retarding growth,
and mortality), some areas gets satisfactory water and the others get over irrigation.
 The draw backs of this simple scheduling system are that excess water could be applied in 24
hours than be absorbed by the soil profile thus leading to wastage. Also, in peak demand conditions and on the
lighter soils cane could become moisture stressed during the latter part of the 15 day cycle.

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3.2.2 The highest priorities of problems and their causes:
As I try to list the problems on project one, it's so huge in number, takes a long time, and needs a maximum
budget. To give a solution for those problems with time and cost is very difficult. Therefore, I select the
following problems based on their importance.
 The Main Problems of this USG:
I. For this under sluice it is impossible for cleaning the gate
The problems of TBSDP Main canal are mentioned bellow:
 Siltation problem 2m of the depth
Surface irrigation problems
 24hr irrigation setting hour per day is the major problem of our project: This is a perennial issue.
Irrigation at night has many disadvantages.
 Field distribution of water is less efficient than in the daytime due to lack of visibility, Such
irrigation is also most unpopular with cultivators for a variety of reasons, and it may be dangerous
(dacoits, wild animals, snakes trodden on in the darkness etc
 For sprinkler irrigation site, applying water at uniform level irrespective of the soil, growth
stage, and growing month, It is not considered the system actual water application and crop
water requirement because of no water measurement device

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4. METHODOLOGY
4.1 Assessmentofthe existing irrigationpractices anditsproblem
Assessment of current irrigation practice was done by referring the feasibility and design study document,
field observation, field report and by physical contact with Technical responsible Staffs such as Irrigation,
and Plantation Staff. The assessment contained: i) frequency of irrigation, ii) irrigation setting hour per
day, iii) application of water with respect to soil, growing month and growth stage, iv) sprinkler water
application efficiency and distribution uniformity, v) pipe breakage and leakage, hydrant valve and
nozzle leakage and breakage, irrigation system service, care and maintenance.
4.2 Data CollectedMethods
4.2.1 Primary Data Collected
Various types of primary data have been collected through formal and informal survey approaches. Field
surveys, house hold surveys, key informant interviews with respective stakeholders and group discussions
have been deeply practiced for cross comparison and wellbeing of information gathering and analysis.
4.2.1.1 Equipment used
The materials used to collect the primary data were Auger, 36m flexible drag hoses which connect the
hydrant and the sprinklers, stopwatch, tape meter, hydrant pressure gauge, and other related accessory
materials
4.2.1.2 Soil Data
Representative soil samples at a depth of 0-30 and 30-60cm were taken randomly at TM3 and TM2 fields
using auger hole. Currently these selected fields are covered with cane and the samples were considered
the lowest, medium and highest spot of the fields, and the sample depths were considered the average
root depth concentration of 60cm. Field capacity and permanent wilting point were tested using pressure
plate membrane at Amhara Design and Supervision Works Enterprise, Soil Chemistry and Water Quality
Section Laboratory, Bahir Dar

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4.2.1.3 Silt measurement:
 To silt measurement 30 places with staff meter and tape meter with in one kilometer difference
I.no location of the sample
depth from
top(m)
volume of
silt(m3)
remark
1 0 1.45
137700
2 3km from head work 1.38
141480
139320
125280
113400
6 15km from head work 2
108000
27000
16200
5400
5400
total
819180
Figure 5 : sample of silt measurement
4.2.1.4 PressureMeasurement
The actual hydrant valves operating pressure along lateral which deliver water for the sprinklers were
measured using hydrant pressure gauge. The recorded pressures were included from the first lateral end
up to the last end of hydrant positions. The gauge was held from the hydrant valve to record the operating
pressure of the hydrant. The hydrant pressure measurements were taken before the catch- cans were
overturned to the start of sprinklers discharge record and collection of precipitations. Because of, the
absence of pressure gauge with pitot tube to measure the nozzles operating pressure the following
empirical formula was used to determine the nozzle operating pressure:
𝑞 = 𝑐𝑎√2𝑔ℎ …………………………………………………………………………4.1
q = nozzle discharge m3/s, a= cross section area, h= hydraulic head m, g= acceleration of gravity, 9.81
m/s2, C = coefficient, it was calculated with equation 4.1 by using the design values of q = 1.8 m3/hr, h=
3.0 bar and nozzle diameter d = 5.0 mm, the obtained value of c was 1.0.

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4.2.2 SecondaryDatacollected
4.2.2.1 CropRootdepthand Cropcoefficient
According to survey data made at Fincha and Metahara Sugar Estates by Habib (2001) and Solomon
(2010), the root depth and crop coefficient values for sugar cane at different growth stages were
summarized below:
Table 3: Root depth and Crop coefficient at different cane ages
Cane age (months) Root depth (cm) Crop coefficient
0-3 30 0.55
3-6 45 0.9
6-15 60 1.05
Above 15 90 0.7
Source: (Habib, 2001 and Solomon, 2010)
In Ethiopian Sugar Estates similar cane varieties are grown, and cane management practices have been
done. The study area soil has similarity with Fincha Sugar Estates .Thus, in this study also the same root
depth and crop coefficient values with respect of their growing stages were used. Booker Tate (2009)
recommended, considering top 60cm as an effective rooting depth was appropriate to estimate soil
moisture eficit for irrigation timing of sugarcane. This was to protect the crop from moistures stress in its
effective root area.
4.2.2.2 ClimaticDataused
The climatic data collected for Pawi Metrology Station. It is located at a geographical location of 36.4
degree longitude, 11.3 degree latitude, and 1119 m above mean see level. The data used were 16 year
rainfall, 10 year maximum temperature, 16 year minimum temperature, 15 year sunshine hour, 10 year
relative humidity, 5 year wind speed

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5. SOLUTION FOR TANA BALES IRRIGATION PROBLEMS
1. WEIR, HEAD REGULATOR AND UNDER SLUICE
Some of our head work problems are solved by getting very high priorities from head office and from our
project. Solved problems are mentioned below:
 Problem of painting antirust (solved)
 Problem of clump cover of rope(solved)
 Wear maintenance(solved)
Figure 6: before and after maintenance of wear

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It was really challenging to construct the weir and other components of the head work structure inside the river,
this is because of the difficulty for river flow temporary diversion works.
Therefore, it was difficult to have simple temporary diversion works prior construction to make the flow out of
the river. The construction was done with prior diversion of the river flow by constructing coffer dam and by
pass canal in the right side of the river in such a way that construction of weir and its appurtenant structure is
executed.
The main head work problems mentioned as follow:
1. Under sluice with full big trees and others
Solution for problem number1: Installing Jeep crane to clean under sluice frequently
Jib crane is a kind of simple system used for lifting and transporting loads in semi circles or full circles
around their support structures. It can cover certain sections of your facility or to supplement a large bridge
crane. 1 ton jib crane can be designed in different styles with different characteristics depending on the
specific needs of your application, and each crane style may differ in area of rotation, purpose, mounting
style, crane beam type and overall dimensions
The main types of jib crane include pillar mounted jib crane, wall traveling jib crane, free standing jib crane,
mast type jib crane, floor mounted jib crane, and 360° jib crane and so on.
In case of our project I select pillar-mounted jib crane because of the following advantages:
 wide adaptability,
 high efficiency,
 high safety,
 novel design,
 time and energy saving,
 ease of mounting and operation etc
This jib crane is installed on the floor needing no support from the building; it mainly consists of up
pillar, down pillar, jib boom, electric chain or wire rope hoist, slewing mechanism and other electric parts
and accessories.
For this purpose the following parameters are needed to solve the problem:
 Lifting Capacity: 0.5t
 Valid Radius: 3-15m
 Lifting Height: 8m
 Slewing Angle: 0-360°
 Lifting Speed: 8m/min
 Slewing Speed: 1r/min

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Figure 7 : Jib crane for head work
3.2 MAIN CANAL
The vast and time taking construction part of this project was the 2nd phase of construction that was
construction of main canal and cross drainage structures. This part of the construction includes construction of
main canal made of geo-membrane, masonry and simple rocky, one measuring flume, fourteen flumes seven
of those are made of shear wall and seven of those are made of masonry, walls ,two bridges ,one canal
empting structure ,one over flow structure ,nine pipe culvert out of which S are single while 4 are double,
seven super passage ,three aqueduct structure 6 head regulator ,three cross regulator ,one sediment settling
basin and huge intake pond at the end .of the canal to distribute the water for each trunk mains and Ayma left
primary canal to 10000ha command areas and Ayma left command areas respectively.
The selected problems of TBSDP Main canal are mentioned bellow:
 Siltation problem
Solution for Main canal problem : siltation
One of the most important and at the same time most difficult conditions to ensure in the operation of an
irrigation canal, is that no silting shall take place in it. The origin of the increased sediment transport into canal
is from erosion on land or activities in the water. The erosion source is typically soil degradation , leading
to soil erosion, especially in fine-grained soils such as loess. The result will be an increased amount of silt and
clay in the water bodies that canals. This siltation decreases life span of canal and increase maintenance cost.
Siltation affects water distribution; its accumulation can create hazards, including diversion of water from its
original channel and the sediments can gradually fill reservoirs, suffocate spawning beds, clog or damage water
inlets and gates. Water systems can also be blocked, causing reduced water flow leading to limited water usage
for irrigation and agriculture and other areas like transportation.
In other case, this cannel is affected with weed and this wed damages the canal capacity to carry and pass
required amount of water to intake structure.
Our canal affected with sediment, weeds and also trees, around Half depth of it capacity is filled with silt and
weed.
The solution to sediment problem in the irrigation system has been tried to incorporate during the design of
the irrigation canal either by conveying and distributing them to the farms or by accumulating in the canals
from where they can be removed time to time.
Sediments in irrigation is associated with various problems like, raising of the bed levels, clogging of the
turnouts and flow control structures like gates, reduction in the conveyance capacity and increase in surface
level of agricultural fields.
These problems will bring more management difficulties in the system. The deposition in the canal will
create back water effect in the canal which lifts the water in the upstream of the deposition. Also, if the
sediments are diverted to the fields for deposition, this might increase their surface level making it more

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difficult to irrigate. Moreover, the deposition of unfertile sediment on the agricultural area can seriously
hamper the production and productivity due to reduction in soil fertility.
Sediment transport is the movement of particles from one place to other due to the effect of gravity or
carried away by the mediums like water, winds and glaciers. When the shear force applied by the flow
becomes higher than the weight of the particles, the transport of the sediment is initiated. Depending on
the flow condition and the sediment characteristics, the sediment are transported in two different forms as
bed load and as wash load.
The bed loads are the sediment particles which are heavier and are moving along the canal bed in sliding,
rolling and jumping action. The movement of bed loads is more governed by inter granular collision than
the flow turbulence. Suspended sediment consist some parts of bed loads, which are supported by fluid
turbulence and some parts of wash load. These are carried in lower or middle part of the channel. Wash
loads are the finer particles which move along with water as part of flow. There is no clear distinction
between wash load and suspended load. As cited by Biedenharn, Thorne, & Watson (2006) Yang and
Simões (2005), Knighton (1998) and Richards (1982) assumed that the size of wash loads is below 0.063
mm which is the borderline between the sand and silt in Wentworth scale.
The solid fractions larger than 2 µm (0.002 mm) are generally considered as sediments in engineering practice.
In general the sediment transport cycle are completed in four stages asdescribed by: (Crosato, 2010)
.
 Weathering: this starts with the weathering of rocks into smaller particles and fragments.
 Erosion and Transport: Water, wind, glaciers and different activities of plants and animals lead
to the soil erosion where the soil particles are detached from the surface and are carried away.
 Deposition: The eroded materials are then deposited. The depositions are mainly on flood plains,
deltas or the areas where there are obstructions or velocity gets lower.
 Lithification: The deposited sediments get compacted over the period of time and starts forming
rock.
The main causesof thissiltationproblemof TBSPCanal are:
 There is no cleaning schedule( no Long rich excavator)
 There is no road beside the canal
This problem may solve by the following:
 Preparing Cleaning schedule
 Installing good trash rack
Preparing Cleaning schedule:
Maintenance of sedimentation devices often involves: sediment and trash removal, fixing clogged pipes,
or addressing invasive vegetation. The performance of a sedimentation practice is often dependent upon
the continuous maintenance activities undertaken. The practice will eventually lose the performance that
it had as a new device unless it is maintained on a regular basis.

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Siltation most often it is caused by soil erosion or sediment spill. Sediment entry into irrigation channels
can occur both from natural causes such as heavy runoff and human behaviour such as overgrazing or
deforestation
Siltation affects water distribution; its accumulation can create hazards, including diversion of water from
its original channel and the sediments can gradually fill reservoirs, suffocate spawning beds, clog or
damage water inlets and gates. Water systems can also be blocked, causing reduced water flow leading
to limited water usage for irrigation and agriculture and other areas like transportation.
In order to safe our canal from this siltation problem we have to the following cleaning schedule :
 Using long reach excavator to cleaning canal
 Installing trash rack with in small distance.
Using long reach Excavator cleaning canal:
Our canal today is filled with sediment and silt around 50% from the total volume.

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Figure 8: Long reach excavator
Specifications
 Max. digging reach : 18.53 m
 Max. digging reach ground: 18.1 m
 Max. digging depth:14.4 m
 Max. cutting height:14.8 m
 Max. dumping height: 12.5 m
 Min. swing radius: 6.2 m
 Bucket digging force: 83.6kN
 Arm crown force: 48.1kN

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Installing good trash rack
Trash racks are metal structures installed in the Canal system to prevent the entrance of large debris, which
can damage irrigation system and blockage of pipe.
 Selection of trash truck: Trash racks are classified into many types based on their constructional
features and the methods of installation:
Type 1: Removable Racks
The racks installed between side guides or grooves are provided in the trash rack structure so that they
can be easily removed by lifting them from guides. These racks shall be used for all major trash rack
installations where a portion of the rack is deeply submerged.
Type 2: Removable Racks
In this type, the individual sections are placed adjacent to each other laterally and in an inclined plane to
obtain the desired flow area. The rack section is secured in place with bolts located above the waterline
for easy removal. Type 2 racks shall be used for canal head works and pumping plants where a single
rack section extends from the water surface to the bottom of the rack. For our canal I recommend this
one.
Type 3: Fixed Racks
In fixed racks, the rack sections are bolted in place below the waterline. Type 3 racks shall be used with
power-driven cleaning rakes that are required for cleaning them. These types of racks are commonly used
for intakes that are submerged.
The selection of the type of trash racks depends upon the following parameters:
1. Accessibility for maintenance or replacement
2. Size and quantity of trash expected
3. Mechanism available for raking.
Inclination of Trash Racks
1. The trash racks must be installed in slanting positions except for guided racks, which can be
installed in a vertical position.
2. For manual cleaning of the racks, the slope should be 1 vertical to 1/3 or 1/2 horizontal.

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Figure 9: Inclination of trash racks
Construction and Installation ofTrash Racks
1. The trash bars shall be fabricated from flats with rounded edges.
2. The lateral support to the bars shall be provided intermediately between the end supports.
3. If spacers are required, they should be placed as far away from the upstream face of the bars as
feasible to avoid interfering with the rake's movement.
4. The panel bars should be directly in line with the corresponding bar above or below so that the
cleaning rake operates satisfactorily while passing up and down the screen.
5. The trash rack sections must be manufactured in light enough parts to be removed and replaced
manually.
DesignRequirements for Maintenance of Trash Racks
1. Cleaning of racks at regular intervals should be arranged in a suitable manner.
2. The frequency with which the racks are cleaned would be determined by the rate at which trash
accumulates.
3. At any given moment, no more than 33% of the trash rack space should be permitted to clog the
racks.
4. The platform's level should be set so that the water level in the canal falls below the platform's
level at least once a year.
5. Each rack should include hooks to allow for lifting the rack in Type 2 for cleaning

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6. For our purpose we need 4m*6m dimension, use three in one at a point and we need within 5km.
therefore total number of trash racks are 18.
02
Figure 10 : Dimension of our trash rack
Solutionfrom infield problems:
As I mention above our project uses two types of irrigation:
 surface irrigation and
 sprinkler irrigation
Surface irrigation problems
24hr irrigation time is the major problem of our project: This is a perennial issue. Irrigation at night has
many disadvantages. Field distribution of water is less efficient than in the daytime due to lack of
visibility, although evaporative losses may be lower. Such irrigation is also most unpopular with
cultivators for a variety of reasons, and it may be dangerous (dacoits, wild animals, snakes trodden on in
the darkness etc). Reluctance to remain in the fields at night contributes to the poor field application
efficiency, as irrigation streams are often left untended, running to waste or flooding
Sugar cane by its nature 2–6 m (6–20 ft) tall with stout, jointed, fibrous stalks that are rich in sucrose,
which accumulates in the stalk internodes and cover the whole furrow line. Because of it leaves it’s
impossible to walk in furrow line at mid-night. The other main problem of our site is there is no
electricity.
6m
4m

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Therefore in case of Tana bales it’s impossible to work over 24 hour irrigation time. Maximum irrigation
time for this site is in between 12 hours only. To solve this problem I recommend the following:
I. increase pipe size
II. redesign new line
III. Night storage:
Solution number one and two needs huge amount budget and resource: incase of this night storage is best
solution:
Night storage:
Ponds or small reservoirs can be extremely important water storage structures for the irrigated farm.
Some reasons for constructing water storage ponds are to:
 collect water from small spring flows so that it can be used efficiently when needed in large flow
rates;
 provide overnight storage of canal water that is available at night;
 store water for times of critical need; and
 Regulate flow.
Construction of over-night storage facilities allow the employer to collect and store secondary canal
water, which otherwise would have been passed unused and burn 12 hour with irrigating the site.
Night storage reservoirs (NSR) could be built if the irrigation scheme is large enough to warrant such
structures. They store water during times when there is abstraction from the water source, but no
irrigation. Irrigation would then be practiced during day time using the combined flow from the
conveyance system and the NSR. Depending on the size of the scheme one could construct either one
reservoir located at the highest part of the scheme or a number of reservoirs, each located at the entrance
of a block of fields. The conveyance system ends at the point where the water enters the reservoir.
In selecting a site for a pond, one should consider
 The location of the water supply,
 Availability of water,
 The soils, and
 The topography of the site.
Location of the pond:
One should not normally construct ponds and small reservoirs in streams, ponds, gullies, or places where
severe storms could create high flows that would wash away the dam. Small, off-stream ponds and
reservoirs generally will not have to handle intense storm runoff.The pond should be located on or above
the highest part of the farm to avoid the need for pumping. Water can flow freely from the pond. The
pond should be located down slope from the water supply, unless water must be pumped to a higher
elevation.

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Preferably water will flow freely from the source to the pond. A topographic survey will indicate the
correct elevations to optimize flow from the water source to the pond
Generally,one literpersecondwill allow the farmertoirrigate one hectare of land.If waterfroma source will be
storedand emptiedata giveninterval fromthe pond,the pondmustbe able toholdthe maximumamountof
waterthat the farmerneedstohold.Our site areais around 1832ha and needs1.9m3
/sof water.
Soils
Ponds should be as impermeable as possible to prevent leakage. The soils should contain a layer of
material that is impervious and thick enough to prevent excessive seepage. Clays and silty clays are
excellent for this purpose; sandy clays are usually satisfactory. Coarse-textured sands and sand-gravel
mixtures are highly pervious and, therefore, usually unsuitable. The absence of a layer of impervious
material over part of the ponded area does not necessarily mean that you must abandon the proposed site.
However, the pond will have to be sealed in other ways.
You can generally determine if the soil has sufficient amounts of clay by wetting it, feeling it in your
hand, and squeezing it between your fingers. If the soil can be molded, and if it can be ribboned out
between the thumb and forefinger, the clay content is usually adequate.
Topography
Generally, reservoirs 2 to 3 meters in height can be constructed by any small-scale farmer if the design
and construction are proper. Topography may determine the type of pond that can be built. Sloping
topography will allow the farmer to fill and drain ponds using gravity. The topography may determine
whether the farmer will be able to build an above-ground or below-ground reservoir or pond.
Some ponds are made by constructing a dam across a creek bed or gully to intercept water that would
otherwise be lost after rainfall or to intercept water coming from a small creek or spring. This is possible
only for very small watersheds that do not develop high flows during severe storms. One must be careful,
however, to provide spillways and bypasses for excess water. Offstream ponds connected to a stream
diversion structure provide protection against failures due to flooding
Designand construction
A pond consists of 4 components - the walls (dikes or levees), the floor, the inlet works, and the outlet
works. The walls should be impermeable (or nearly) and capable of withstanding the pressure exerted
outward by the pond. The floor must be as nearly impermeable as possible. The inlet works must be able
to receive the expected amount of water. The outlet works should have the ability to regulate flow from
the pond and also provide for the overflow of excess water.
Figure below provides some ideas for outlet works. Inlets often consist of a simple pipe of sufficient
diameter to carry the maximum expected inflow. The Rivaldi valve (a flexible irrigation hose that can be
submerged to allow water to flow from the pond) provides a convenient means of regulating the outflow,
as does the siphon tube(s)

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SPRINKLER IRRIGATIONS PROBLEM:
In our project the biggest sprinkler irrigation is irrigation interval or irrigation scheduling: to get good
productivity we have to solve this problem.
Calculating IrrigationSchedule:
Various methods and tools have been developed to determine when crops require water and how
much irrigation water needs to be applied. The reference evapo-transpiration was calculated
using the computer program called CROPWAT which is developed by FAO. The program is
based on Modified Penman-Montieth method.
For calculation of evapo-transpiration a long year metrological data is needed but due to the
absence of representative long year data, the two years data generated from the newly
established pawi metrological station in the project site was used for estimation of reference
evapo transpiration through the CROPWAT software. The following meteorological factors
were taken into consideration for calculation of Reference Evapotranspiration by Modified
Penman- Montieth Method: maximum and minimum temperature, relative humidity, wind
velocity and sunshine hours (Allen et al, 1998)
After the references evapotranspiration (ETo) was estimated, the crop water requirement (ETc)
was estimated using the equation. Then, the effective rainfall was calculated using USDA
method in CROPWAT software. (FAO 56)

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The soil classification and their properties generated by WWDSE (2011) were used. (WWDSE
2011) Information for some Important crop characteristics (growth stages, crop coefficients and
factor of depletion) information were taken from literatures and other country`s experience as
they are not yet determined for local conditions; but cane rooting depth survey result at Finchaa
was used with some modification.
The relationship between Reference Evapotranspiration (ETo) and crop evapotranspiration the
crop water requirement is expressed though crop coefficient (Kc) as:
ETc = Kc * ETo ...................................................(Equation 1)
Depth of application was calculated using the following formula.
Dn = TAW * ρ * Dr ................................................. (Equation 2)
Where, TAW = total available water (mm/m),
ρ = allowable depletion (fraction),
Dr = effective root depth (m),
Dn = Net depth of application (mm),
The irrigation interval (I) in days was estimated using the following formula:
I = Dn/Etc ............................................................... (Equation 3)
The irrigation scheduling was determined by equations (2) and (3).
Data used
The crop characteristics parameters important for the determination of irrigation schedule
are length of each growth phase, crop coefficient and rooting depth. However, none of this
information is identified for sugarcane in a well designed experiment in Ethiopia. Thus,
the respective values were adopted from other research in other countries.

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Accordingly, by integrating information in FAO publications’ and experience gained from
Mauritius crop coefficient values in table 1 were used. However, the lengths of growth
periods were slightly modified to fit the conditions at the project area.
Table 4: Description of sugarcane (KC)
Irrigation Schedule
Various methods and tools have been developed to determine when crops require water
and how much irrigation water needs to be applied. The irrigation scheduling was
determined by equations (2) and (3).
Depth of irrigation application
The first component of irrigation schedule is gross irrigation depth, which highly depends on the
irrigation methods and its flexibility, perceived net application depth, and application efficiency.
Ideally, at the beginning of the growing season, the amount of water given per irrigation
application, also called the irrigation depth, is small and given frequently. This is due to the low
evapo transpiration of the young plants and their shallow root depth. During the mid season, the
irrigation depth should be larger and given less frequently due to high evapotranspiration and
maximum root depth. Thus, ideally, the irrigation depth and/or the irrigation interval (or
frequency) varies with the crop development.
When sprinkler and drip irrigation methods are used, it may be possible and practical to vary both
the irrigation depth and interval during the growing season. With these methods it is just a matter
crop
Init.
Stage Dev. Stage
Mid
Stage
Late
Stage total(Days)
sugarcane
50 70 220 140 480
kc in kc mid kc end
0.2 1.2 0.7
Maximum Root
Depth(m)
Depletion Fraction2 (for ET= 5
mm/day)
1.2-2.0
0.65

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of turning on the tap longer/shorter or less/more frequently. When surface irrigation methods are
used, however, it is not very practical to vary the irrigation depth. With surface irrigation,
variations in irrigation depth are only possible within limits. Irrigating cane fields by varying the
depth of application based on the growth stage is not also practiced in the Ethiopian sugar
industries due to its difficulty for management. It is difficult to control the flow and the cutoff of
time for furrow irrigation in which the water delivery method is bank breaching (opening a cut in
the banks of a field canal to discharge water into the field). Therefore, it is often sufficient to
estimate or roughly calculate the irrigation depth and to fix the most suitable depth; in other
words, to keep the irrigation depth constant over the growing season. (REPORT, 2012)
The net depth of application based on 90cm rooting depth (rooting depth at full growth of cane),
design application efficiency of 80% and furrow length of 100m were estimated and presented
below.
Table 5: Net and gross depth of application
For best control of irrigation application depth, selection of inflow rate and cut off time combinations is
vital; the implementation requires flow and time measurement. Later in the field use, these combinations
of flow rate cut off time are converted to cut off ratio. Cutoff ratio is a time required for water to advance
to the end of the field to the total set time. This is because our volume control mechanism is based on
advance distance of water front. However, cut off ratio has not been determined for they are
Procedure of CROWAT
1. Calculation of ETo: by using metrological data ETo is calculated as following table:
Soil types Net depth (mm) Gross depth (mm)
Clay 122 152
Silty clay 111 139
Sandy loam 86 107
Sandy clay 65 81

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Table 6: ETo of Tana bales
When this ETo shown by chart/graph, it look like as follow:
Graph 1: Graph representation of ETO
2. Calculating Effective rain fall:

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Table 7 : Effective Rainfall of pawi station
3. Calculating crop coefficient:

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Graph 2: Description of sugarcane coefficient
4. Calculating soil moisture content and available water content:
Table 8: soil moisture content and available water content
5. Check CWR table:

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Table 9 : CWR representation
Graph 3: Graphical representation of irrigation required

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6. Check irrigation scheduling table from CROP WAT:

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Table 10: irrigation scheduling
Graph 4: Graph Representationofirrigationscheduling

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Another output data
I. No Description Result remark
1 ETo 2.94 mm/day
2 Total annual eff. rainfall 749.1mm
5 Total life age of sugarcane 480days
6 Average Height of sugarcane 3m
7 Irrigation intervals 10days
Table 11: output data of tana bales
The recommended sprinkler set time and irrigation interval for Black Cotton (Vertisol) soils are tabulated as
below:
Sprinklers set-time (hours)
Age of
cane
Oct Nov De
c
Jan Feb Mar Apr May
0-30 6 6 6 6 6 6 6 6
31-60 6 6 6 6 6 6 6 6
61-90 12 12 12 12 12 12 12 12
91-120 12 12 12 12 12 12 12 12
121-150 12 12 12 12 12 12 12 12
>150 12 24 24 24 24 24 24 24
30d before
dry off
12 24 24 24 24 24 24 24
30d before
harvest
0 0 0 0 0 0 0 0
Promoted 12 24 24 24 24 24 24 24
Irrigation Interval (days)
Age of
cane
Oct Nov Dec Jan Feb Mar Ap
r
May

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0-30 8 8 8 8 8 8 8 8
31-60 8 8 8 8 8 8 8 8
61-90 15 15 15 15 15 15 15 15
91-120 15 15 15 15 15 15 15 15
121-150 15 15 15 15 15 15 15 15
>150 15 20 20 20 20 20 20 20
30d
before
dry off
15 20 20 20 20 20 20 20
30d
before
harvest
0 0 0 0 0 0 0 0
Promoted 15 20 20 20 20 20 20 20
Table 12 : recommended sprinkler set time and irrigation interval
Based on the results obtained the following recommendations are drawn, total net irrigation required is
567.2mm and total gross irrigation required is 810.2mm.
As we determine by CROPWAT Irrigation water Interval of Tana Beles sugar development project is
10days.
Therefore we have to change 14 days of irrigation interval to 10 days.
ADDITIONAL MATERIALFOR THIS ADJUSTMENET
Now a day our project use 15 days irrigation interval for sugarcane plant, but it’s out of recommend one
as I indicate above and changed to 10 days interval. When we change this irrigation interval it need
additional resources like human resource, flexible hose and sprinkler tripod.
In case of previous irrigation interval for one hectare we use two tripod and two flexible hose, but for Ten
days irrigation interval tripod and hose should be increase over one hectare we have to add another one
hose and tripod.
For the total area of our site we need additional 15000 numbers of hose and tripod

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Figure 11: comparison of 10 days with 15 days

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6. CONCLUSIONS AND RECOMMENDATIONS
 The system performance and sustainability is under question that;
 any large debris can pass easily through the trunk main up to the sprinkler nozzle
 There is no common fixed cleaning week for the whole system.
 Thus; system pipe close, breakage and leakage are daily and weekly actions.
 The current sprinkler irrigation scheduling under taken by the project was not suit with the current
actual water application, also it is not considered the soil, growing month, stage of growth, Thus, improved
irrigation scheduling with respect to the soil, growing month, stage of growth, and the existing actual water
application efficiency is very important.
 The project has to be award that the sprinkler infield irrigation system is working below the design
capacity. The lateral spacing 90m and sprinkler spacing 18*18m in some fields were not within the design
specification.
 Therefore, to keep and sustain the system performance; it is better to follow operation, care and
maintenance of the whole system from the gravity off take up to the sprinkler nozzle as per the Feasibility and
Design Study document guideline (2013).
 The project command area is bisected by rivers and streams which provide a natural drainage
network. Additional (smaller) drainage channels and associated structures are however necessary to:
(i) ensure safe removal of excess irrigation / rainfall from the bench terraces to avoid soil
erosion; and
(ii) To prevent water logging, salinity builds up and associated crop loss in the flatter land. The
surface drainage system should ensure that surface water from heavy rainfall (10 year return
period) is removed from the fields within 24 hours.
(iii) Ensure long rich excavator is very special for cleaning the entire canal
(iv) Another very important is installing trash rack within 5km of the canal length at 450
(v) For surface irrigation night storage is recommended
(vi) For sprinkler irrigation we have use new standard on this project

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APPENDIX
Appendix 1 Average rainfall data, mm
year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
1998 0.0 0.0 9.8 9.6 153.6 511.9 392.8 366.6 243.0 146.7 5.6 0.0
1999 2.2 0.0 0.0 35.5 180.7 280.9 285.7 359.2 273.1 134.6 19.2 4.5
2000 0.0 0.0 2.1 61.2 188.7 264.8 199.9 365.2 186.9 213.1 23.5 2.0
2001 0.0 0.7 0.0 4.9 100.3 296.3 417.4 503.5 247.9 167.7 0.0 6.4
2002 0.0 0.0 0.0 8.3 10.3 344.8 243.3 355.7 190.0 139.7 23.3 0.0
2003 0.0 0.0 8.0 1.8 21.8 306.2 402.3 352.1 301.9 109.3 15.9 0.0
2006 9.2 11.2 0.0 18.0 152.7 226.6 399.9 660.2 263.4 191.8 5.9 0.0
2007 0.0 0.0 1.9 36.5 120.2 417.3 348.7 400.7 313.7 69.9 27.3 0.0
2008 2.2 1.0 0.0 53.1 151.6 290.1 490.8 409.1 240.5 42.9 13.0 0.0
2009 0.0 0.0 3.2 0.0 42.1 301.1 378.5 140.9 159.1 58.9 6.3 0.0
2010 5.2 0.0 0.0 24.1 71.0 270.3 435.1 418.1 242.4 185.9 6.4 0.0
2011 0.0 0.0 5.0 6.7 181.6 132.3 237.2 362.0 247.6 80.5 0.2 0.0
2012 0.0 0.0 0.0 0.2 0.0 216.2 511.5 597.0 286.4 140.5 26.0 4.6
2013 0.0 0.0 0.0 0.0 186.3 204.9 606.3 632.8 308.1 91.6 48.6 0.0
2014 0.0 0.0 26.3 74.5 192.3 233.3 279.3 303.0 284.7 226.4 0.0 0.0
2015 0.0 0.0 0.0 0.0 190.6 149.6 176.1 247.8 232.1 94.6 50.1 0.3
Appendix 2 Average minimum temperature, 0C
Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
1998 14.9 15.7 20.9 20.8 22.7 21.6 20.8 20.0 19.4 17.8 15.3 13.4
1999 14.7 18.3 17.6 23.0 21.9 20.6 20.3 19.6 18.9 18.8 15.8 15.7
2000 16.1 18.3 21.5 23.2 22.7 20.7 19.7 19.2 18.4 18.6 16.1 14.9
2001 13.6 17.9 20.4 23.9 23.0 20.5 20.3 20.2 19.6 19.9 16.0 15.6
2002 15.0 18.6 22.3 24.9 24.2 21.9 20.6 19.9 19.2 19.2 17.7 15.2
2003 15.6 20.6 21.9 18.1 18.9 17.2 19.1 18.6 18.2 18.9 16.2 15.0
2004 13.7 16.7 19.2 20.8 20.5 20.1 19.9 19.5 19.0 17.9 15.3 13.5
2006 12.9 15.6 16.7 17.8 17.1 17.8 17.1 16.7 17.5 17.6 14.5 12.2
2007 11.7 13.8 18.1 19.0 19.5 17.7 18.2 17.6 17.4 16.3 14.3 11.1
2008 13.5 14.3 16.9 20.1 19.2 18.2 18.0 17.9 17.8 16.9 13.8 12.9
2009 13.2 18.1 19.3 19.5 19.9 19.2 18.0 18.6 17.7 17.0 14.5 13.5
2010 14.1 15.6 17.4 22.2 21.0 18.9 18.5 18.6 18.1 18.3 16.0 11.5
2011 13.2 14.3 18.2 21.9 20.0 19.2 18.3 17.6 18.0 17.2 14.1 13.2
2012 13.7 15.7 19.1 19.0 19.5 18.4 17.8 17.5 17.7 16.8 15.2 13.2
2013 13.6 20.9 18.7 18.6 19.4 18.9 17.3 17.8 17.6 17.2 14.4 11.6
2014 12.1 13.6 18.5 19.7 19.5 18.7 18.5 18.0 17.6 17.5 15.2 12.7
2015 12.4 15.7 19.8 20.4 20.1 18.4 18.5 18.0 17.6 17.9 16.4 14.3

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Appendix 3 Average maximum temperature, 0C
Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
2006 35.6 37.3 38.0 38.0 34.4 31.8 30.6 29.0 28.6 29.8 31.1 32.1
2007 24.9 26.7 37.8 37.5 34.5 29.7 27.2 27.1 28.5 30.6 32.4 33.9
2008 34.3 35.8 38.8 35.0 33.5 29.6 27.8 27.8 29.8 30.4 32.7 33.8
2009 35.2 37.0 37.9 37.5 36.3 32.7 27.1 27.9 29.7 30.4 33.6 33.8
2010 34.7 34.6 36.1 39.2 35.2 30.5 27.4 27.2 28.5 30.7 32.3 33.0
2011 34.2 37.2 37.0 38.1 34.0 30.6 28.2 27.6 28.8 31.2 32.7 33.8
2012 34.9 37.5 38.4 38.2 35.2 32.5 27.9 27.9 28.3 30.7 31.6 33.1
2013 35.0 37.3 38.2 38.6 35.0 30.9 27.5 27.4 29.5 30.1 32.0 33.1
2014 34.6 35.4 36.4 35.5 31.9 30.2 28.4 27.8 28.9 29.9 32.1 32.5
2015 33.8 37.4 38.4 37.7 34.4 30.8 29.8 29.2 29.8 30.7 31.4 31.3
Appendix 4 Average sunshine hours, hr
year JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
2001 10.4 10.2 9.1 9.4 8.3 6.8 5.0 5.0 7.1 8.6 8.8 9.7
2002 9.7 9.5 9.4 10.5 10.7 8.3 7.2 5.5 7.0 9.4 9.3 10.2
2003 10.5 9.3 9.8 10.0 9.7 7.6 5.4 5.0 6.5 9.1 9.8 10.2
2004 9.8 10.0 9.5 9.5 10.0 7.4 6.9 5.7 6.4 8.0 9.4 10.0
2005 9.7 9.5 9.1 8.7 8.2 6.3 4.7 4.7 6.4 8.0 9.5 9.9
2006 9.9 9.8 9.4 9.8 7.1 6.0 4.3 3.5 6.1 6.6 9.6 9.8
2007 9.4 8.8 9.1 9.5 7.8 6.3 3.7 4.3 7.3 8.2 9.7 10.1
2008 9.2 9.6 9.9 7.7 7.9 6.9 5.9 4.9 6.3 7.8 10.0 10.0
2009 10.1 8.7 8.6 8.7 8.6 8.1 3.9 8.2 7.3 6.7 9.9 9.9
2010 9.7 8.9 7.7 9.2 7.2 6.4 3.7 3.5 5.6 7.4 9.2 9.3
2011 9.3 10.2 8.5 9.5 7.3 7.4 4.2 5.2 5.9 8.1 9.6 10.0
2012 10.0 9.4 9.2 10.2 8.4 6.0 4.6 4.6 5.8 8.4 8.6 10.0
2013 9.4 9.6 9.4 10.0 8.6 5.5 4.3 4.3 6.6 6.8 9.2 9.9
2014 9.1 9.9 8.7 8.0 7.0 6.3 4.7 4.7 5.2 9.9 9.5 9.9
2015 9.6 9.6 9.2 9.8 7.0 6.6 6.4 5.8 6.3 7.4 8.9 6.6
Appendix 5 Average relative humidity, %
year JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
2006 50 40 30 63 68 88 60 86 92 87 83 76
2007 53 42 72 71 83 82 93 95 94 92 89 84
2008 79 76 77 83 86 89 91 94 93 90 86 83
2009 81 78 75 0 76 86 89 94 92 92 86 83
2010 71 68 64 78 86 87 93 92 91 91 90 86
2011 85 80 79 72 82 86 91 93 92 87 83 77
2012 73 64 60 68 67 76 87 90 89 84 81 74
2013 73 63 57 55 62 80 89 90 88 84 77 78

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2014 76 71 76 67 80 86 86 88 87 84 76 77
2015 78 75 77 75 84 90 87 80 92 90 90 79.9
Appendix 6 Average wind speed, m/se
Year JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
2011 0.5 0.6 0.6 0.8 0.9 0.9 0.7 0.7 0.5 0.3 0.5 0.5
2012 0.6 0.6 0.6 0.6 0.8 1.0 0.7 0.7 0.5 0.3 0.2 0.3
2013 0.5 0.5 0.6 0.6 0.8 0.6 0.6 0.7 0.8 0.6 0.7 0.7
2014 0.4 0.6 0.8 0.8 1.0 0.6 0.5 0.4 0.4 0.4 0.3 0.4
2015 0.5 0.6 0.7 0.8 0.7 0.6 0.6 0.4 0.3 0.3 0.3 0.5
Appendix 7 probability of dependable rainfall estimation
year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Rank Prob(%)
1998 9.2 11.2 26.3 74.5 192.3 511.9 606.3 660.2 313.7 226.4 50.1 6.4 1 6%
1999 5.2 1.0 9.8 61.2 190.6 417.3 511.5 632.8 308.1 213.1 48.6 4.6 2 12%
2000 2.2 0.7 8.0 53.1 188.7 344.8 490.8 597.0 301.9 191.8 27.3 4.5 3 18%
2001 2.2 0.0 5.0 36.5 186.3 306.2 435.1 503.5 286.4 185.9 26.0 2.0 4 24%
2002 0.0 0.0 3.2 35.5 181.6 301.1 417.4 418.1 284.7 167.7 23.5 0.3 5 29%
2003 0.0 0.0 2.1 24.1 180.7 296.3 402.3 409.1 273.1 146.7 23.3 0.0 6 35%
2006 0.0 0.0 1.9 18.0 153.6 290.1 399.9 400.7 263.4 140.5 19.2 0.0 7 41%
2007 0.0 0.0 0.0 9.6 152.7 280.9 392.8 366.6 247.9 139.7 15.9 0.0 8 47%
2008 0.0 0.0 0.0 8.3 151.6 270.3 378.5 365.2 247.6 134.6 13.0 0.0 9 53%
2009 0.0 0.0 0.0 6.7 120.2 264.8 348.7 362.0 243.0 109.3 6.4 0.0 10 59%
2010 0.0 0.0 0.0 4.9 100.3 233.3 285.7 359.2 242.4 94.6 6.3 0.0 11 65%
2011 0.0 0.0 0.0 1.8 71.0 226.6 279.3 355.7 240.5 91.6 5.9 0.0 12 71%
2012 0.0 0.0 0.0 0.2 42.1 216.2 243.3 352.1 232.1 80.5 5.6 0.0 13 76%
2013 0.0 0.0 0.0 0.0 21.8 204.9 237.2 303.0 190.0 69.9 0.2 0.0 14 82%
2014 0.0 0.0 0.0 0.0 10.3 149.6 199.9 247.8 186.9 58.9 0.0 0.0 15 88%
2015 0.0 0.0 0.0 0.0 0.0 132.3 176.1 140.9 159.1 42.9 0.0 0.0 16 94%

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Bibliography
Allenetal.(1998).
Crosato.(2010).
design,A.(2013). report.
Design,T.F.-F.(2013).
ESC. (2012).
FAO56.
(2013). Feasibilityand Design Study of TBISDP.
Hailegebriel.S.(2007).
(2009). PawiAgriculturewheatherdatastation.
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WWDSE 2011.

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