NPDES Storm Water Program: Phase II

The Clean Water Act Amendments of 1987 established the NPDES storm water program.  This act required implementation in two separate phases.  Phase I generally addressed the most significant pollution sources in storm water runoff.  PHASE II addressed other sources of runoff to protect water quality.  The Phase II regulations were published in the December 8, 1999, Federal Register.

The dates below are approximate. Specific compliance dates will be set by each NPDES permitting authority as it changes appropriate regulations and issues general permits.

December 8, 1999 The final Phase II rule is published in the Federal Register, with Conditional No Exposure Exclusion option available 60 days later for facilities for which EPA is the permitting authority.

October 2000 (1 year from the date of signature of the final rule): EPA is obligated to issue a menu of recommended BMPs for regulated small MS4s.

October 2001 (1 year after the issuance of the menu of BMPs): EPA is obligated to issue guidance on the development of measurable goals for regulated small MS4s.

December 8, 2002 (3 years from the date of publication of the final rule): The NPDES permitting authorities are required to issue general permits for Phase II regulated small MS4s and small (less than 5 acre) construction activity.

March 10, 2003 (3 years and 90 days from the date of publication of the final rule, or by the time specified in the permit): Operators of Phase II regulated small MS4s and small construction activity are required to obtain permit coverage.

By the end of their first permit terms (typically 5 years), operators of regulated small MS4s would have to fully implement their storm water management programs.