For many years, civil engineers have approached stormwater management with the idea that the best solution is to eliminate the rainwater as quickly as possible. This approach was rooted in the need to get water out of the medieval streets so you were not constantly slogging through puddles. A great deal of energy has been spent studying runoff coefficients and sizing pipes to obtain maximum efficiency in stormwater removal. Significant consequences of this historic “rapid runoff” design approach are being felt in modern urban societies. As stormwater volumes increase downstream, flooding can result. Furthermore, contaminants washed off of pavements and other hard constructed surfaces convey the water away from the property, which can concentrate downstream.

A more sustainable way to manage stormwater is taking hold with many civil engineers: Low-Impact Development (LID). Low-impact site development is an alternative approach that seeks to maintain the natural hydrogeologic character of the property or region. This is accomplished by both alternative site design and specific best water flow management practices. A key goal of LID is to control the volume of stormwater runoff such that stormwater leaving the site after development is approximately the same volume of stormwater that left the site before development. ...

You need to register to view the rest of the article. Click here to subscribe.