ARS | Publication request: Low Impact Development Design—Integrating Suitability Analysis and Site Planning for Reduction of Post-Development Stormwater Quantity

Submitted to: Sustainability
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 14, 2010
Publication Date: August 3, 2010
Citation: Wang, X., Shuster, W., Pal, C., Buchberger, S., Bonta, J.V., Avadhanula, K. 2010. Low Impact Development Design—Integrating Suitability Analysis and Site Planning for Reduction of Post-Development Stormwater Quantity. Sustainability. 2(8):2467-2482.

Interpretive Summary: An analytical technique was developed to incorporate physical and hydrological spatial characteristics within an experimental, agricultural watershed to determine the location of impervious components for urban development of an undeveloped watershed. The objective of the study was to develop a land suitability analysis (LSA) so that runoff at the watershed outlet from large storms would be minimized. The study integrated open-space conservation principles, based on watershed physiographic and soil characteristics, to derive a low-impact development (LID) residential plan for a three hectare site at the North Appalachian Experimental Watershed near Coshocton OH, USA. A widely used engineering method (“curve number method”) for estimating total runoff depths expected from different frequency storms was used for four landscape plans in the watershed: (i) the pre-development condition, (ii) a conventional design, (iii) LID design based on the LSA of same building size; and (iv) LID design based on the LSA with reduced building footprints. Post-development runoff depths for the conventional design increased by 55 percent over those for the pre-development condition. Runoff depth for the same building size LSA-LID design was only 26 percent greater than that for the pre-development condition, and only 17% for the design with reduced building sizes. Results suggest that prudent use of LSA may improve prospects and functionality of low-impact development, reduce stormwater flooding volumes and, hence, lower site-development costs. Reducing runoff volumes could also possibly minimize downstream erosion and water-quality problems.

Technical Abstract: A land-suitability analysis (LSA) was integrated with open-space conservation principles, based on watershed physiographic and soil characteristics, to derive a low-impact development (LID) residential plan for a three hectare site in Coshocton OH, USA. The curve number method was used to estimate total runoff depths expected from different frequency storms for: (i) the pre-development condition, (ii) a conventional design, (iii) LID design based on the LSA of same building size; and (iv) LID design based on the LSA with reduced building footprints. Post-development runoff depths for the conventional design increased by 55 percent over those for the pre-development condition. Runoff depth for the same building size LSA-LID design was only 26 percent greater than that for the pre-development condition, and 17% for the design with reduced building sizes. Results suggest that prudent use of LSA may improve prospects and functionality of low-impact development, reduce stormwater flooding volumes and, hence, lower site-development costs.