The U.S. Environmental Protection Agency (EPA) recently published a final rule to reduce stormwater pollution from construction sites (“Effluent Limitations Guidelines and Standards for the Construction and Development Point Source Category”). The new rule takes effect in February 2010 and will be phased in over four years. Federal stormwater regulations (40 C.F.R. § 122.26) require certain dischargers engaged in construction activity to obtain a National Pollutant Discharge Elimination System (NPDES) permit under the Clean Water Act and to implement certain control measures to manage discharges. Construction activities, the largest category of dischargers under the NPDES permitting program, include among other things clearing, excavating, and grading. As such, these new regulations will impact a large number of businesses and a broad range of activities.

Current NPDES regulations for construction sites lack national performance standards and monitoring requirements. The new rule, however, is intended to work with existing state and local stormwater programs to provide a technology-based “floor,” including Effluent Limitation Guidelines (ELG) and New Source Performance Standards (NSPS) for all construction dischargers. This is the first time that EPA has imposed national monitoring requirements and enforceable numeric limitations on construction site stormwater discharges.