Section 405 of the Water Quality Act of 1987 (WQA) added section 402(p) of the Clean Water Act (CWA), directed the United States Environmental Protection Agency (USEPA) to develop a phased approach to regulate storm water discharges under the National Pollutant Discharge Elimination System (NPDES). The USEPA published a final regulation in the Federal Register on the first phase (Phase I) of this program on November 16, 1990, establishing permit application requirements for "storm water discharges associated with industrial activity." These regulations defined the term "storm water discharge associated with industrial activity" in a comprehensive manner to cover a wide variety of facilities. Construction activities, including activities that are part of a larger common plan of development or sale, that ultimately disturb at least five acres of land and have point source discharges to waters of the U.S. were included in the definition of "industrial activity" pursuant to 40 CFR 122.26(b)(14)(x).
Phase II of the storm water program was published in the Federal Register on December 8, 1999, and required NPDES permits for discharges from construction sites disturbing at least one acre, but less than five acres, including sites that are part of a larger common plan of development or sale that will ultimately disturb at least one acre but less than five acres, pursuant to 40 CFR 122.26(b)(15)(i).
National Pollutant Discharge Elimination System (NPDES), Stormwater Final Rules: