Watt Field Drainage

1. Watt Field Drainage Solutions
Libby Zanin, Benjamin Rawls, Emma Coleman

2. Objective
● Problem: Drainage issues on the field in front of
the Watt Innovation Center
● Design Goals:
○ Decrease ponding in the field
○ Control erosion and runoff 1
○ Maintain or increase aesthetics

3. Design Considerations

4. Soil Replacement
● Cecil-Hiwassee-Pacolet,
general soils map of South
Carolina from 19972
● Hydrologic Soil Group
(HSG) B
● Moderate infiltration rate
● Improve to HSG A

5. Drain Installation
● University Solution
○ 3 drains
● Remove 9 gallons per minute at
maximum3
● From model 529 gallons per a
minute for just a 5 year storm
● Fast flow rate
○ erosion at site and discharge
location

6. Land Management
● Currently grass cover
● 7 revisions explored
with shrubs
○ Top and bottom
■ 20ft
■ 30ft
○ Complete cover
○ Top
■ 20ft
■ 30ft
○ Bottom
■ 20 ft
■ 30ft

7. Design Selection
● Soil Replacement
○ Too expensive
○ Highly labor intensive
○ Hinders use of brand new building
● Drain Installation
○ Lack of erosion control
● *Land Management*
○ Low maintenance, non invasive option
○ Possibly increase aesthetics and functionality
○ Potential to decrease erosion

8. Methods

9. Methods
● Determination of field size, slope, and soil type
○ Web Soil Survey
● Find Peak Flow Rate of 25 year storm
○ WNTR 55 Model
● Determine the amount of runoff and sediment loss from
each land management revision
○ WEPP Models

10. WNTR 55 Model

11. WEPP Models

12. Results

13. WEPP Model Results Summary
Land Management Average Annual Runoff (in) Average Annual Soil Loss (ton/A)
Current- Grass 7.18 0.474
Shrubs at Top (20ft) 6.97 0.448
Shrubs at Top (30ft) 6.85 0.444
Shrubs at Bottom (20ft) 6.88 0.523
Shrubs at Bottom (30ft) 6.89 0.590
Shrubs at Top & Bottom (20ft) 6.36 0.470
Shrubs at Top & Bottom (30ft) 6.11 0.527
Shrubs Complete Cover 5.51 0.346

14. Chosen Land Management
● Shrubs complete cover
chosen
○ Erosion reduced by 27%
○ Runoff reduced by 23%
● Theoretical design would
include sitting areas along with
plants

15. Relevance to Hydrology &
Importance of Project

16. Relevance & Importance
● Universal Annual Soil Loss Equation: T = R K LS VM
○ Soil replacement- K- soil erodibility factor
○ Land management- VM- vegetative mulch factor
● Land management to reduce
erosion
● Watt is LEED-silver certified
○ Usable open space can add
points to the scorecard

17. Conclusions

18. Conclusions
● Solution: Revised landscaping of Watt Field
○ Plant:
■ Shrubs
■ Perennials
■ Trees
○ Create usable open space:
■ Benches
■ Tables
● Design Goals:
○ Improves aesthetics and functionality of space
○ Decreases runoff and erosion (23%, 27%)

19. Questions?

20. References
1
Brander, K. E., Owen, K. E., & Potter, K. W. (2004). Modeled Impacts Of Development Type
On Runoff Volume And Infiltration Performance. Journal of the American Water
Resources Association J Am Water Resources Assoc, 40(4), 961-969.
doi:10.1111/j.1752-1688.2004.tb01059.x
2
General soil map of South Carolina, 1997 [Map]. (1997). Columbia, SC: South Carolina Dept.
of Natural Resources, Land Resources and Conservation Districts Division. Retrieved
April 10, 2016, from http://www.ces.clemson.edu/scmaps/cartography/Digitized
Maps/SoilsMap.jpg
3
University of Minnesota. (2016). Drainage calculator. Retrieved April 23, 2016, from
http://www.extension.umn.edu/agriculture/water/online-calculator/#flowrate