What is Phase II of the National Pollution Discharge Elimination System (NPDES)?
The Phase II stormwater rule represents the second step in the Environmental Protection Agency’s (EPA) effort to preserve, protect, and improve our nation’s water resources from polluted stormwater runoff.
Phase I of the NPDES program began in 1990 and required medium and large municipal separate storm sewer systems (MS4s) to obtain NPDES coverage.
The expanded Phase II program began in March 2003 and requires small MS4s in urbanized areas to obtain NPDES permits and implement six minimum control measures:
Public education and outreach on stormwater impacts
Public involvement and participation
Illicit discharge detection and elimination
Construction site stormwater runoff control
Post construction stormwater management in new development and redevelopment
Pollution prevention/good housekeeping for municipal operations
Additional information regarding the NPDES program can be found by visiting the EPA website.