Phase I and Phase II
Phase I In response to the 1987 Amendments to the Clean Water Act (CWA), the U.S. Environmental Protection Agency (EPA) developed Phase I of the NPDES Storm Water Program in 1990. The Phase I program addressed sources of stormwater runoff that had the greatest potential to negatively impact water quality.
Phase II The Phase II Final Rule, published in the Federal Register on December 8, 1999, requires NPDES permit coverage for stormwater discharges from: Certain regulated small municipal separate storm sewer systems (MS4s); and Construction activity disturbing between 1 and 5 acres of land.
Note: The builder must file for a permit and is required to complete a SWPPP and complete weekly inspections with related BMPs necessary for compliance.
