Overview

Stormwater management is an important design and construction practice. Without proper management, the resulting runoff can cause many problems including flooding and poor water quality. Traditionally, the design of stormwater facilities is taught in hydrology and watershed management classes. These types of courses are important to stormwater management, but focus more on the big picture, not individual construction projects. The purpose of this chapter is to look at stormwater management from the construction and individual site perspective so that it can be better integrated into the LEED or green building process. However, the actual design of any stormwater management system should be done by practitioners experienced in civil engineering systems, hydrology, and watershed management in addition to these newer concepts.

The concepts that are of most interest for stormwater management are the rate of stormwater runoff from a site or area, the amount of stormwater runoff from an area, the pollutant loadings from the runoff, and the impact on erosion and subsequent pollution that runoff has on the downstream areas. Over the decades many methods have been developed to estimate runoff. They are used for calculating rates, volumes, and a concept referred to as the time of concentration. A simplified definition of the time of concentration is the time it takes for various runoff contributions from a defined site or area to come together to a point producing a peak rate at that point. Akan and Houghtalen (2003) list three methods for determining the time of concentration: the...