Minimizing Pond Size Using an Off-Site Pond in a Closed Basin: A Storm Flow Mitigation Design and Evaluation

Minimizing Pond Size Using an Off-Site Pond in a Closed Basin: A Storm Flow Mitigation Design and Evaluation


Florida State University, Panama City, Civil and Environmental Engineering Program, Florida, U.S.A

George and Associates Consulting Engineers, Inc., Tallahassee, Florida, U.S.A

30 April 2014
| Citation



Construction of large on-site detention pond to manage the stormwater runoff in the project area is not only expensive, but also a waste of developable land. To minimize the pond size, a systematic design of storm flow routing followed by model verification is necessary. This study presents a challenging stormwater management design for a site located in a complex urban setting at Tallahassee, Florida, USA. The site, a 4.6-hectare (11.4 acre) wooded area, was developed into a swimming pool complex resulting in increased post-development runoff. This increased runoff was managed by designing an on-site pond, minimized by placing it in series with an existing downstream off-site pond of a closed basin. The available storage of the downstream pond was efficiently used to reduce the upstream pond size. To minimize the on-site pond, the design considered re-arrangement and re-sizing of pre-development basins that allowed releasing some portion of post-development runoff below its pre-development level in the directions where it was allowed to drain. The excess runoff generated from the area was routed through the on-site pond and discharged into the existing off-site pond, where all runoff was retained to meet the guidelines of a closed basin. The short duration simulation results (8-hr and 24-hr design storms) confirmed significant off-site runoff reduction for the post-development condition. Besides short duration simulations, the extended simulation results (for the entire 1-yr period) also revealed that the on-site and off-site ponds can jointly manage all extreme runoff including the runoff of a historical extreme wet year.


Closed basin, design evaluation, extended simulation, land development, runoff, SCS curve number, stormwater


[1] Jang, S., Cho, M., Yoon, J., Yoon, Y., Kim, S., Kim, G., Kim, L. & Aksoy H., Using SWMM as a tool for hydrologic impact assessment. Desalination, 212, pp. 344–356, 2007. doi: http://

[2] Sear, R.T. & Ravenswaay, B.V., Efficient sizing of stormwater treatment ponds. Proc. of the Water Resources Sessions at Water Forum ‘92, Baltimore, Maryland, pp. 780–785, 1992.

[3] Yao-Ming Hong, Y.M., Experimental evaluation of design methods for in-site detention ponds. International Journal of Sediment Research, 25, pp. 52–63, 2010. doi: http://dx.doi. org/10.1016/S1001-6279(10)60027-3

[4] Schaad, D.E., Farley, J. & Haynes, C., Design and routing of storm flows in an urbanized watershed without surface streams. Journal of Hydrology, 375, pp. 334–344, 2009. doi: http://

[5] Nascimento, N.O., Ellis, J.B., Ellis, Baptista, M.B. & Deutsch, J.-C., Using detention basins: Operational experience and lessons. Urban Water, 1, pp. 113–124, 1999. doi: http://dx.doi. org/10.1016/S1462-0758(00)00009-1

[6] Ahmad, H. & Miller, J.W., Evaluation of storm flow management design to contain runoff within the watershed using ponds in series. Proc. of the 6th Int. Conf. On Sustainable Water Resource Management, eds. C.A. Brebbia, V. Popov, WIT: UK, pp. 177–187, 2011.

[7] Booth, D.B. & Jackson, C.R., Urbanization of aquatic systems: degradation thresholds, stormwater detection, and the limits of mitigation. Journal of the American Water Resource Association, 33(5), pp. 1077–1090, 1997. doi: tb04126.x

[8] Villarreal, E.L., Inner city stormwater control using a combination of best management practices. Ecological Engineering, 22, pp. 279–298, 2004. doi: ecoleng.2004.06.007

[9] Barner, W.L., Comparison of stormwater management in a karst terrane in Springhill, Missouri – case histories. Engineering Geology, 52, pp. 105–112, 1999. doi: http://dx.doi. org/10.1016/S0013-7952(98)00062-3

[10] Bedient P.B., Huber W.C. & Vieux B.E., Hydrology and Flood Plain Analysis, Prentice Hall, Inc.: New Jersey, 2008.

[11] Soil Survey of Leon County Florida, USDA, Issued February 1981, Online http://soildatamart.

[12] Interconnected Channel and Pond Routing Model (ICPR), version 3.10 (2002), Streamline Technologies, Inc.: Winter Springs, Florida, U.S.A.

[13] State of Florida Department of Transportation (FDOT) (2010) Drainage Manual, Tallahassee Florida. Online, http://

[14] CBasin, version 1.0 (2003), City of Tallahassee Growth Management Department: Florida, U.S.A.

[15] Singhofen, P.J., Calibration and verification of stormwater models. Florida Association of Stormwater Utilities 2001 Annual Conference, June 20–22, 2001 Online http://www. stream