On December 28, 2012, the Los Angeles County National Pollutant Discharge Elimination System Municipal Separate Storm Sewer System Permit (MS4 Permit) became effective upon adoption by the Los Angeles Regional Water Quality Control Board. This new MS4 Permit establishes the waste discharge requirements for stormwater and non-stormwater discharges within the watersheds of Los Angeles County. The MS4 Permit includes provisions that allow Permittees to develop either a Watershed Management Program or an Enhanced Watershed Management Program (EWMP) to address water quality issues.

EWMPs include the following elements:

1. Watershed water quality priorities, known and suspected pollutant sources, and prioritization of water quality issues in the watershed.
2. Existing and potential control measures within the watershed.
3. EWMP Plan implementation schedule.
4. Public and stakeholder input.
5. Adaptive management framework.
6. Estimate of implementation costs and financial strategy.

The EWMP for the Marina del Rey watershed is a collaborative effort of the EWMP Agencies, comprised of the County, Los Angeles County Flood Control District, and the cities of Los Angeles and Culver City. The Marina del Rey EWMP covers the areas owned by the MS4 Permittees within the watershed, but does not include the area owned by the State of California adjacent to the Ballona Wetlands nor the California Department of Transportation (Caltrans) right-of-way, as these agencies are not part of the Marina del Rey EWMP Watershed Management Group.

Copies of the original drafts and most recently revised version of the Marina del Rey EWMP can be found on the Los Angeles Regional Water Quality Control Board website for the Marina del Rey Watershed Management Group. You can also view and download a PDF copy of the most recently revised version here.