Cal. Code Regs. tit. 23 § 3991
The California Regional Water Quality Control Board, San Diego Region (San Diego Water Board) adopted Resolution No. R9-2012-0033 on June 13, 2012, an amendment to the Water Quality Control Plan for the San Diego Basin (Basin Plan) that incorporates a Total Maximum Daily Load (TMDL) for Sediment in Los Peñasquitos Lagoon. The State Water Resources Control Board approved this amendment under Resolution No. 2014-0001 on January 21, 2014.
The purpose of the TMDL is to restore and protect the beneficial uses of the Los Peñasquitos Lagoon. The watershed numeric target for the TMDL was set equal to natural sediment loadings, and the lagoon numeric target was set equal to 80 percent of the total saltmarsh acreage present in 1973 prior to intensive urban development. When the sediment TMDL is achieved, the Lagoon will once again meet the applicable water quality standard for sediment.
The TMDL establishes an Implementation Plan that requires responsible parties to jointly reduce the current sediment loading by 67 percent, and to restore tidal and non-tidal saltmarsh toward 346 acres with a 20-year compliance schedule. The TMDL will be implemented primarily through National Pollution Discharge Elimination System (NPDES) permits for the Phase I and Caltrans municipal separate storm sewer systems (MS4s), and through statewide storm water general NPDES permits for Phase II MS4s, industrial, and construction sites. Other discharges identified as significant sources of long-term sediment loadings into the watershed will also be required to implement the TMDL through appropriate regulatory mechanisms issued by the San Diego Water Board.
Regulated parties must ensure that their facilities prevent erosion and sediment discharges through the implementation of control measures (e.g., site planning, sediment and erosion controls) and monitoring and reporting requirements. Certain dischargers that have potential for long-term sediment loadings into the Los Peñasquitos Lagoon watershed must also participate in efforts to monitor and measure the progress of watershed sediment load reductions and improvements in saltmarsh habitat acreage.
Cal. Code Regs. Tit. 23, § 3991