Santa Margarita Water Quality Improvement Plan


Agencies involved in the development of the Santa Margarita Water Quality Improvement Plan (WQIP) include the California Department of Transportation, the County of Riverside, the Riverside County Flood Control and Water Conservation District, the County of San Diego, and Cities in Riverside County – Menifee, Murrieta, Temecula and Wildomar. The WQIP is a requirement of updated stormwater regulations adopted by the Regional Water Quality Control Board (Regional Board) according to Order No. R9-2013-0001, as amended by Order Nos. R9 2015-0001 and R9-2015-0100. The ultimate goal of the WQIP is to protect, preserve, enhance, and restore water quality of receiving water bodies. These improvements in water quality will be accomplished through an adaptive planning and management process that identifies the highest priority water quality conditions within the watershed and implements strategies to address them.

The Santa Margarita Water Quality Improvement Plan was recently submitted to the Regional Board. The San Diego Water Board will issue a public notice and release the WQIP for a public review and comment period for a minimum of 30 days. The complete Santa Margarita River Water Quality Improvement Plan, Provisions B and F and WMAA can be found at here. Instructions for providing comments on the document to the Regional Board can be found on their website.

For Copermittee contact information, please check out the Santa Margarita Stakeholders page.


Water Quality Data

Monitoring data used in the development of the WQIP can be found on the California Environmental Data Exchange Network (CEDEN) website,

Geographic Information System (GIS) Data

Available GIS data, layers, and/or shapefiles used to develop the maps generated by the Copermittees for the Water Quality Improvement Plans and Annual Reports can be accessed through the link below:

Santa Margarita GIS data files

For jurisdiction-specific data, please contact the appropriate stormwater Copermittee for additional resources.

County of San Diego Data

Santa Margarita Watershed Management Area Analysis (WMAA) Data

Typically, the WMAA is presented as an appendix to each watershed’s WQIP; however, there is also a regional component to the WMAA. The Santa Margarita Watershed Management Area Analysis is currently undergoing discussion. 

Other Data

All data that were used to develop the WQIP but do not fit into one of the above categories can be found in the document archive.