Download to read offline
![As-Built Riser
● Increase in peak discharge
considered unacceptable
Circumstances
Return Period of 24-Hour Storm
Event [Years]
Description Year 2 10 25 100
As-Built Existing 2020 2.70 11.28 16.70 24.79
Proposed (Valve-
Open)
2021 2.70 11.28 16.70 24.79
Failure (Obstructed) 2021 3.24 12.38 18.28 24.76
Peak Discharge Rates (cfs) of Bargain Foods Dry Pond](https://image.slidesharecdn.com/finalpresentation-201120004116/75/Final-presentation-72-2048.jpg)
![Proposed Riser
● Maintains lower proposed
condition
● 25 year-event exception
● Failure condition held to
moderate discharge rates
Circumstances
Return Period of 24-Hour Storm
Event [Years]
Description Year 2 10 25 100
As-Built Existing 2020 2.70 11.28 16.70 24.79
Proposed (Valve-
Open)
2021 2.48 9.98 17.88 24.66
Failure (Obstructed) 2021 2.89 10.91 17.57 26.03
Peak Discharge Rates (cfs) of Bargain Foods Dry Pond](https://image.slidesharecdn.com/finalpresentation-201120004116/75/Final-presentation-74-2048.jpg)
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Final presentation
- 1. Design of anActive Control Outlet in a Stormwater Drainage Basin Rose Degner, Paige Kimble, Brandon Perkins & Pa-Sweet Betancourt Clemson University, Clemson, SC October 22, 2020
- 2. Outline • Introduction • Background •Rationale • Objective(s) • Approaches • Literature Review • Materials and Methods • Results • Recommendations • Acknowledgements
- 3.
- 4. Background - ClimateChange • Warming climate • Atmosphere holds more water • More frequent and more intense storms 50 year trends in river discharge
- 5. Background - GrowingUrban Development • Global population is growing • Countries are becoming more urban • 55% world population • Increasing development leads to increasing impervious surface areas Urbanization in the past 500 years for 4 major countries and the world
- 6. Background - ImperviousSurface Area • Impervious surface areas • Less infiltration • Higher rates of runoff • 1.1 year return period storm • Natural peak flow: 82.45 m3/s • Urban peak flow: 209.29 m3/s • Larger storms hitting a larger area of impervious surfaces • Flooding, erosion, water quality Shape of flood hydrographs for surfaces with varying imperviousness
- 7. Background - SmallSolutions • Larger infrastructures needed for extensive flooding • Small changes on a universal scale • Improve widespread water quality • Reduce hydraulic stress on smaller receiving water bodies Stormwater management for a neighborhood Flooding in Philadelphia
- 8. Background - StormwaterRetention Basins • 1987 National Pollutant Discharge Elimination System • Stormwater retention systems used for the first time • Main benefit: Total Suspended Solids (TSS) reduction • Erosion control and flooding management Pre and post development hydrologic cycles
- 9. Background - StormwaterRetention Basins • How do they help? • Runoff retention (TSS settling) • Steady release of the water • Infiltration • Some vegetative uptake • Basin design is for • Certain % TSS removal • Certain storm event • Ex. 10 year, 24 hour storm Stormwater Retention Pond diagram
- 10. Background - StaticOutlets • Open pipe outlet • TSS settles as the water is released • Designed for average conditions • Not always effective for • More intense storms • If field conditions change • Water released to mimic pre- development flows • Young technology • 30 years • Room for improvement Outlet structure at design site (above) Close up of static outlet at design site (left)
- 11. Background - ActiveOutlets • Outlet can be adjusted • Open, partially open, closed • Can consider • Weather forecast • Pond water level • Maximize retention time • Better mimic pre development flow Stormwater basin outlet structure
- 12. Background - ActiveOutlets • Can increase efficiency in • Water pollutant reduction • Basin location • Basin design • Smaller ponds • More cost effective • Better use of land • Can be retrofitted onto pre- existing retention ponds Flow Duration Curves for static and active outlet systems
- 13. Background - SiteInformation • Pre-existing pond in Pelzer, SC • At the base of Bargain Food Store • Main constituent is nutrients • TSS can be used to gauge success • 2004 inflow and outflow data taken by Woolpert • 6 sampling events • 12 samples throughout storm event • Max TSS inlet concentration: 876 mg/L • Average TSS inlet concentration: 124 mg/L • Average % reduction: 56.05% • More site information covered later Satellite image of site with stormwater basin outlined in red
- 14. Rationale ● Increased intensityof rain and continuous urbanization ○ Flooding concerns ○ Water quality concerns ● Active control outlets ○ Stormwater drainage is more efficient ○ Improves stormwater quality ○ Smaller stormwater pond size ○ Can be retrofitted onto current ponds ● Success of active control outlets on large scale ○ Critical to consider efficacy of technology on a small scale
- 15. Objective The objective ofthe project is to design and evaluate the impact of an active outlet control structure for stormwater management applications for water quality and quantity benefit using a pond in Pelzer, SC as a case study.
- 16. Approaches • Task 1:Discuss with Woolpert the extent of the project • Task 2: Review scientific literature on engineering design related to stormwater management • Task 3: Apply adaptive control structure to retention pond for water quality control • Task 4: Determine and assess the site properties (physical, chemical, hydrologic) and collect data (hydrology, topography) • Task 5: Create site exhibits in GIS and input values for modeling • Task 6. Develop a watershed study using EPA SWMM program • Task 7: Evaluate and compare the new models to pre existing models • Task 8: Simulate pre- and post-hydrologic conditions • Task 9: Optimize and Design the active outlet control structure • Task 10: Apply for permits
- 17. Design of an ActiveControl Outlet
- 18.
- 19. Literature Review -Programming • Writing code is out of the scope of this project • Programming Logic Controller (PLC) • Also called a data logger • A data logger - a point of communication between outlet and weather forecast programming • CR1000X data logger from Campbell • Ideal for outdoor conditions ● Where is the data for the program coming from? ● How is the data received and integrated into the program? ● How is the forecasting information used by the data logger? CR1000X Flagship Data Logger from Campbell
- 20. Programming - Whereis the data coming from? • NOAA, or the National Oceanic and Atmospheric Administration • Offers multiple public models • High Resolution Rapid Refresh (HRRR) model (experimental) • Reasonable precipitation predictions, cloud coverage • Resolution of 3-km • Forecasts up to 12h in 1-hour increments; can extend up to 48h in 6-hour increments Picture of 12hr HRRR forecast for Oct 14, 2020
- 21. Programming - Whereis the data coming from? • Weather Prediction Center (WPC) under NOAA also has models • WPC offers long, medium, and short range forecasts • The Quantitative Precipitation Forecasts (QPF) • Focuses on heavy rain, snow events, and flash flooding • Resolution of 20-km • Forecasts in 6-, 24-, and 48- hour increments Picture of 24hr QPC forecast for Oct 14, 2020
- 22. Programming - Whereis the data coming from? • National Centers for Environmental Protection • North American Mesoscale Model (NAM) • Precipitation, lightning, temperature, kinetic energy; good for large storm events (eg hurricanes) • Resolution of 12-km • Short-term weather forecasting Picture of 6hr NAM forecast for Oct 14, 2020
- 23. Programming - Whereis the data coming from? • Global Forecast System (GFS) • Covers the entire globe • Includes wind, precipitation, soil moisture, atmospheric ozone concentration, etc. • Resolution of 18 miles • Predicts weather up to 16 days Picture of 12hr GFS forecast for Oct 14, 2020
- 24. Programming - Whereis the data coming from? • Forecasting model used will depend on: • Area of the stormwater basin • Resolution and time frame desired • Type of forecasting desired • Potentially time of year. • HRRR is sufficient for this design project • Forecasting model used can be updated Picture of 12hr HRRR forecast for Oct 14, 2020
- 25. • Where isthe data for the program coming from? • HRRR forecast from NOAA • How is the data received and integrated into the program? • How is the forecasting information used by the data logger?
- 26. Programming - Howis the data received and integrated into the program? • Forecasts from NOAA can be automated • Pulled from NOAA’s website with a code • Provided as a radar image • With code, received by program as a grib file • Grib file - file format for storage/transport of gridded meteorological data • Degrib - code to decipher the grib file Picture of 12hr HRRR forecast for Oct 14, 2020
- 27. Example screenshot of program(left). These lines of code pull the 18 hour forecast 18 hour forecast output for October 19, 2020 (right) from above code
- 28. Programming - Howis the data received and integrated into the program? • Subcodes written to: • Update the forecast • Specify what to do • Program reading the forecasting data is not enough • Forecast needs to be sent to the data logger
- 29. • Where isthe data for the program coming from? • HRRR forecast from NOAA • How is the data received and integrated into the program? • Both grib files and degrib code can be found on NOAA’s website • How is the forecasting information used by the data logger?
- 30. Programming - Howis the forecasting information used by the data logger? • File and data transfer • Ex. computer browser uses HTTP • Sends/receives data to/from website server • FTP or File Transfer Protocol • One of the oldest and simplest protocols • User can download/upload files to a server • Data logger/server • Unique IP address
- 31. Programming - Howis the forecasting information used by the data logger? • Forecasting program written by Woolpert • Stored on a server in Dayton, OH • Interacts with the data logger located in Pelzer, SC using FTP • Lines of code for: • Getting grib file • Degribbing forecasting data • Using FTP to send information to data logger
- 32. Programming - Howis the forecasting information used by the data logger? • Data logger will receive: • Forecasting information from server • Real time water level from water level sensor • Logic program running on data logger will then: • Determine if outlet needs to be opened or closed • Send appropriate signal to outlet
- 33. • Where isthe data for the program coming from? • HRRR forecast from NOAA • How is the data received and integrated into the program? • Both grib files and degrib code can be found on NOAA’s website • How is the forecasting information used by the data logger? • FTP is used to send forecast to the data logger
- 34. Instrumentation Options Types ofvalves: • Butterfly • Pinch • Ball • Gate • Globe Types of actuators: ● Electric ● Pneumatic
- 35.
- 36. Valve: Butterfly - Butterflyvalves opens, closes and regulates a fluid passage by reciprocating about 90° with a disc type opening and closing member Advantages ● Simple structure, small volume, light weight ● Small flow resistance and opening/closing time ● Low pressure drop, high pressure recovery Disadvantages ● Flow adjustment range is small, open 30% → flow rate 95% ● Difficult to clean ● Difficulty with slurries ● Potential for cavitation and choke
- 37. Valve: Pinch - Pinchvalves have a full-bore design. This means they can intrinsically allow unrestricted flow and ensure complete stoppage. Advantages ● Very clean, excellent drainage ● Inexpensive ● Minimal turbulence ● Low weight ● Low maintenance Disadvantages ● Cannot be used in high temperature applications ● Cannot be used in high pressure applications ● Cannot be used with Gas media
- 38. Valve: Ball - Ballvalve consists of a large sphere with a central hole equal to the inside diameter of the pipe in mounted Advantages ● Maintains and regulates high volume ● Does not require lubrication ● Superior ease of operation ● Low maintenance cost ● High pressure and high temp flow ● Low purchase cost Disadvantages ● Not suitable for throttling applications ● Suspended particles can settle and become trapped, causes: ○ Wear ○ Leakage ○ Valve failure ● Difficult to clean, leads to contamination
- 39. Valve: Gate - Gatevalves work by inserting a rectangular gate or wedge into the path of a flowing fluid Advantages ● Used as shut off valve ● Inexpensive ● Available in large sizes ● Bi-directional ● Suitable for use with slurries and viscous liquids Disadvantages ● Low pressure limitations ● Difficult to repair ● Slow open/close time ● Seat and disk erosion can occur ● Poor throttling characteristics
- 40. Valve: Globe - Globevalves have a spherical body shape with the two halves of the body being separated by an internal baffle. Advantages ● Can be fast-acting ● Precise control ● Can be used in high-pressure systems Disadvantages ● High head loss ● Not good for clean or sterile application ● Low coefficient of flow - Cantilevered mount of disk to stem ● Heavier than other valves
- 41.
- 42. Actuator: Electric - Anactuator requires a control signal and a source of energy. The control signal is relatively low and in this case would be electric voltage or current. Advantages ● Fast and accurate ● Very fast development times for new models ● Possible to apply sophisticated control techniques to motion ● Relatively inexpensive Disadvantages ● Gear backlash limits precision ● Problems of overheating in stalled conditions ● Inherently high speed with a low torque ● Brakes are needed to lock them into position
- 43. Actuator: Pneumatic - Apneumatic actuator requires a control signal and a source of energy. The control signal is relatively low and in this case would be pressurized air Advantages ● Low cost ● Ease at reversion movement ● High speed of moving ● Explosion and fire safe Disadvantages ● Compressibility of air ● Problems of overheating in stalled conditions ● Impossibility to receive uniform air output ● Performance difficulty at slow/constant speed ● Requires good preparation ● Brakes are needed to lock them into position
- 44. Design Criteria • TSSremoval • Driven by detention time • 60% in 24 hour detention time • Greenville County Regulations • 80% TSS removal • 72 hour drawdown of standing water
- 45. Critical Storm 25-year, 24-hourstorm event 6.69-inches of precipitation • Applied to assess how our design reacts under crucial circumstances • Before and after implementation of retrofitting
- 46. Design Storm 10-year, 24-hourstorm event 5.40-inches of precipitation • Applied to determine necessary parameters for design • Before and after implementation of retrofitting
- 47.
- 48. 1. Mapping Software •ArcGIS ArcMap 10.8 2. Modeling Software • EPA SWMM 5.1 1. Programming Logic 2. Basin Delineation & Characterization 3. Modeling Materials Methods
- 49. Materials and Methods- Programming Logic • Many inputs to consider in programming • Current water level • Precipitation forecasts • Local regulations • Logic flowchart was made to visualize • On/off system was assumed • Flowchart can be expanded for partially opening valve Programming Logic Flowchart
- 50. Logic Flowchart Flow chart demonstratingthe logic of active outlet system
- 51. Materials and Methods- ArcGIS ArcMap 10.8 • ArcMap is used to display geographic information as a collection of layers and other elements in a map view • The data frame provides a geographic window that allows the user to display and work with geographic information as a series of map layers • These layers can also be used to store data relevant to the project such as: • Soil Data • Digital Elevation • Geometric Values (Area, Length) • ArcMap also has the ability to perform geoprocessing operations to assist in calculating necessary input values for modeling
- 52. Basin Delineation ● Basindelineation exhibits are used for overall visualization of all stormwater drainage being deposited into the pond via overland flow or pipe network (through yard inlets/junction boxes) ○ 2004 delineation based on 2004 Woolpert area values ○ Current conditions ● The layers present in this view include: ○ Landsat 8 Basemap Imagery: Provides satellite view of the area of study ○ USGS Topo Map: Provides topographic information for delineation of basin & subcatchments ○ Digital Elevation Model: Provides point-coverage elevation data that is compiled into a raster file which displays a connected elevation cover of the land (light green=low elevation to red/white=high elevation) used for delineation of the basin/subcatchments ○ Basin .shp file: Shows delineation of basin for area of study 2004 2020
- 53. ArcMap Data: BasinDelineation ● The geometric calculation of area is based on the basin boundary and stored within the basin .shp file for each year of study ● Drainage basin delineated based on 2004 Woolpert study area provided and replicated effectively ○ Inputs needed for replicate modeling ● Current conditions drainage basin area delineated based on current information and site visits/pictures
- 54. Land Cover ● Landcover exhibits are used to show the land cover classifications of the basin that will be used in the determination of subcatchment curve numbers ● The layers present in this view include: ○ Landsat 8 Basemap Imagery: Provides satellite view of the area of study ○ USGS Topo Map: Provides topographic information for delineation of basin & subcatchments ○ Digital Elevation Model: Provides point coverage elevation data that is compiled into a raster file which displays a connected elevation cover of the land (light green=low elevation to red/white=high elevation) used for delineation of the basin/subcatchments ○ Land Cover .shp file: Shows land cover classification of basin area ○ Basin .shp file: Shows delineation of basin for area of study 2004 2020
- 55. ArcMap Data: LandCover ● The geometric calculation of area is separated by the land cover type and stored within the Land Cover .shp file for each year of study ● Land cover type was determined using aerial imagery as well as site visit information/pictures ● Area and land cover type are also used in the determination of curve number for each subcatchment in each year
- 56. Soils ● Soils exhibitsare used to show the soil types and hydraulic classifications in the watershed that will be used in the determination of subcatchment curve numbers ● The layers present in this view include: ○ Landsat 8 Basemap Imagery: Provides satellite view of the area of study ○ USGS Topo Map: Provides topographic information for delineation of basin & subcatchments ○ Digital Elevation Model: Provides point coverage elevation data that is compiled into a raster file which displays a connected elevation cover of the land (light green=low elevation to red/white=high elevation) used for delineation of the basin/subcatchments ○ Soils .shp file: Shows the soil types and hydraulic classifications in the basin area ○ Basin .shp file: Shows delineation of basin for area of study 2004 2020
- 57. ArcMap Data: Soils ●Geometric calculation of area is separated by soil type and stored within the Soils .shp file for each year of study ● Soil types and hydraulic soil grades obtained from NRCS Web Soil Survey data within basin boundary ● Hydraulic soil grades are classified on an A-D scale based on runoff potential of the soil ○ Lowest potential - A ○ Highest potential - D
- 58. Subcatchments ● Subcatchment exhibitsare used for overall visualization of all subcatchment divisions within the Pelzer Pond Basin ● The layers present in this view include: ○ Landsat 8 Basemap Imagery: Provides satellite view of the area of study ○ USGS Topo Map: Provides topographic information for delineation of basin & subcatchments ○ Digital Elevation Model: Provides point coverage elevation data that is compiled into a raster file which displays a connected elevation cover of the land (light green=low elevation to red/white=high elevation) used for delineation of the basin/subcatchments ○ Subcatchments .shp file: Shows delineation of subcatchments (divided by node method) within basin ○ Basin .shp file: Shows delineation of basin for area of study 2004 2020
- 59. ArcMap Data: Subcatchment ●The geometric calculation of area is separated by each subcatchment and stored within the Subcatchment .shp file for each year of study ● Subcatchment boundaries were determined using the node method ○ Each node (inlet) is divided into individual drainage basins within the Pelzer Pond Basin
- 60. Link Node ● LinkNode exhibits are used to show the existing inlet structures and the pipe linkages connecting them to each other and the pond ● The layers present in this view include: ○ Landsat 8 Basemap Imagery: Provides satellite view of the area of study ○ USGS Topo Map: Provides topographic information for delineation of basin & subcatchments ○ Digital Elevation Model: Provides point coverage elevation data that is compiled into a raster file which displays a connected elevation cover of the land (light green=low elevation to red/white=high elevation) used for delineation of the basin/subcatchments ○ Subcatchments .shp file: Shows delineation of subcatchments (divided by node method) within the basin ○ Node .shp file: Shows the location of inlet structures (white) within the basin ○ Link .shp file: Shows the piping (green) connecting the inlet structures to each other and the pond ○ Basin .shp file: Shows delineation of basin for area of study 2004 2020
- 61. ArcMap Data: LinkNode ● Nodes are placed over inlet structures located within the Pelzer Pond Basin ○ Aerial imagery ○ Site visit observations ○ Names stored in Node .shp file ● Links are drawn following the underground pipe linkages connecting each node to the pond ● The link lengths are determined using a geometric calculation operation and stored in the Link .shp file
- 62. Slope ● Slope exhibitsare used to show the overland flow path within each sub catchment. ● The layers present in this view include: ○ Landsat 8 Basemap Imagery: Provides satellite view of the area of study ○ USGS Topo Map: Provides topographic information for delineation of basin & subcatchments ○ Digital Elevation Model: Provides point coverage elevation data that is compiled into a raster file which displays a connected elevation cover of the land (light green=low elevation to red/white=high elevation) used for delineation of the watershed/subcatchments ○ Subcatchments .shp file: Shows delineation of subcatchments (divided by node method) within the basin ○ Node .shp file: Shows the location of inlet structures (white) within the basin ○ Slope .shp file: Shows the overland flow path (orange) from highest, furthest elevation in the subcatchment from the inlet structure to the inlet structure ○ Basin .shp file: Shows delineation of basin for area of study 2004 2020
- 63. ArcMap Data: Slope ●The overland flow path is draw within each subcatchment from the furthest, highest elevation point to the inlet structure (node) ● Upslope and downslope elevations are obtained by using the information tool on the digital elevation model layer at each endpoint of the overland flow paths ○ Elevations stored in the Slope .shp file ● Slopes are then calculated using length and elevation values for each subcatchment
- 64. Methods and Materials- EPA SWMM 5.1 Stormwater Management Model • Water quantity and quality modeling for urban watersheds • Developed to aid local, state, and federal stormwater management by reducing runoff • Facilitate the incorporation of our design to the industry • Many capabilities and options for stormwater routing User interface for as-built Pelzer model.
- 65. EPA SWMM 5.1Limitations • Limited memory • Rain event duration and time interval • Limits continuous modeling • Urban-watersheds • Developed to combat urbanization • Makes assumptions of infiltration in pervious areas that are exaggerated in rural watersheds • Quality of user provided data Bargain Foods development
- 66. Model Validation • 2004amendments to watershed required permitting by Greenville County • Approval was granted based on a model prepared in Microsoft Excel • Conditions were replicated in EPA SWMM to verify the software’s similarity to validated design calculations • Finalized variables estimated from a small range of values Hydrograph derived using Microsoft Excel in 2004
- 67. Models 2004 Permitted Existing ●6” orifice with bleeders ● Watershed properties from historical data 2020 As-Built Existing ● 2.5” orifice, 3 overflow weirs knocked in the structure ● Watershed properties from current public data and field measurements Proposed Modifications ● Dynamic valve covering existing 2.5" orifice ● Keep all other spillways from as- built condition ● Tweak weirs and orifices as necessary
- 68. Modeling an ActiveControl Outlet By Pond Depth and Simulation Time 1. Find freeboard threshold depth of collection pond 2. Find pond drawdown time 3. Manipulate Control Options by If/Then Statements a. For pond depth b. For holding time Control Rules determine how pumps and regulators in the conveyance system will be adjusted over the course of a simulation.
- 69.
- 70.
- 71. Model Validation Permitted conditions(2004) Duplicate effective permitted conditions (2004)
- 72. As-Built Riser ● Increasein peak discharge considered unacceptable Circumstances Return Period of 24-Hour Storm Event [Years] Description Year 2 10 25 100 As-Built Existing 2020 2.70 11.28 16.70 24.79 Proposed (Valve- Open) 2021 2.70 11.28 16.70 24.79 Failure (Obstructed) 2021 3.24 12.38 18.28 24.76 Peak Discharge Rates (cfs) of Bargain Foods Dry Pond
- 73. Implementation of V-NotchPlate Before After
- 74. Proposed Riser ● Maintainslower proposed condition ● 25 year-event exception ● Failure condition held to moderate discharge rates Circumstances Return Period of 24-Hour Storm Event [Years] Description Year 2 10 25 100 As-Built Existing 2020 2.70 11.28 16.70 24.79 Proposed (Valve- Open) 2021 2.48 9.98 17.88 24.66 Failure (Obstructed) 2021 2.89 10.91 17.57 26.03 Peak Discharge Rates (cfs) of Bargain Foods Dry Pond
- 75. Risk Assessment Any thoughtson where this section should go? If not, I can just stick it here, before the recommendations
- 76.
- 77. Features: • 304 StainlessSteel construction • Clevis design and horizontal bolting stabilizes gate, proper alignment • Multi-layer square packing provides exceptional gland sealing • Unique body design, enables self draining • Zero leakage isolation • Lugged body suitable for all mounting orientations Built for: • Severe service performance • Low pressure applications Bray: Series 940 Knife Gate Valve
- 78. Rotork: IQ3 -Multi-turn Features: • Continuous positions tracking at all times, even without power • Detailed trend analysis and diagnostic data available for asset management • Increased protection by using independent torque and position sensing • Remote operation, configuration and commission up to 100m from actuator • Safe, motor-independent, handwheel operation available at all times • Real time valve and actuator performance information viewable on screen • Easy installation and maintenance using detachable thrust bases • Explosion proof to international standards • Oil bath lubricant provides extended life and the ability to mount in any orientation • On power loss, graphical interface, remote indication and data logger are maintained and accessible ● 3rd Generation Intelligent Actuator
- 79. Programming Specifications • Keepwater level just below depth of weirs • Time to drain pond from holding depth to outlet invert is 17.5-hours • Open outlet 56.5 hours into a 24-hour storm event to drain by 72-hours
- 80.
- 81. Acknowledgements • Ben Hammond,Woolpert • Dr. Christophe Darnault, Clemson University • Dr. Rui Xiao, Clemson University
- 82.