Selecting and Designing BMPs to Meet Regulatory Requirements.

Certain types of municipal, construction, and industrial stormwater are regulated under the National Pollution Discharge Elimination System permit program. Stormwater permits require permittees to meet water quality targets, such as Total Maximum Daily Load allocations and antidegradation. To minimize the amount of stormwater runoff and associated pollutants discharged to surface waters and meet permit requirements, there is an increasing focus on managing stormwater as close to its source as possible.  This entails implementation of infiltration practices, such as bioinfiltration (rain gardens) and permeable pavement, and enhanced filtration practices, such as iron enhanced systems. Proper selection, design, construction, and maintenance of these stormwater practices is critical. Soil and engineered media are essential considerations in this process, affecting the feasibility, type, size, and performance of these practices. This discussion focuses on the selection and design of stormwater management practices, in particular the role of soil and engineered media, in meeting regulatory requirements.