dc.description.abstract | This study begins with a systematic evaluation of the quality of 76 local plans within the Chesapeake Bay watershed in order to better understand whether local jurisdictions have thoroughly integrated the concepts of sustainable stormwater management into their comprehensive plans.
The study first examines which specific factors may contribute to explaining the variation in plan quality. Second, this study explores the impact of planning capacity on mean and peak annual runoff. By employing multivariate regression analyses, the degree of association of planning factors and other contextual variables with mean and peak annual runoff was investigated for 75 sub-basins.
The Chesapeake Bay watershed was chosen for the investigation because the bay has been severely polluted by urban and suburban stormwater runoff resulting from the rapid growth of its nearby jurisdictions. The watershed covers approximately 166,000 km^2 and encompasses seven states in the Mid-Atlantic region.
The study results show that most local jurisdictions are likely to have relatively weak comprehensive plans integrating the principles of sustainable stormwater management, with an average plan score of 22.55 out of 50. The results of multiple regression analyses further identify that an impervious surface and a plan’s adopted year positively impact plan quality, while previous flooding and storm surge events negatively influence the quality of local plans. This study also demonstrates that sub-basins that were included in jurisdictions with relatively high plan quality scores tended to generate higher volumes of peak annual runoff. Whereas, sub-basins included in jurisdictions with more planners are likely to produce less mean annual runoff. In addition, the results suggest that surface runoff can be significantly affected by impervious surface, average basins slope, basin shape, precipitation, historical flash flood events, natural drainage density, floodplain, and soil characteristics.
This study concludes with policy implications and recommendations to increase awareness and understanding of sustainable stormwater management concepts as well as how local planning efforts and capacities may effectively contribute to the mitigation of surface runoff and flash flooding. | en |