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The Santa Margarita Watershed drains the southwest portion of Riverside County including areas of the Cities of Menifee, Murrieta, Wildomar, and unincorporated County of Riverside, and all of the City of Temecula. Stormwater runoff from these areas collects into Murrieta and Temecula creeks and combines to form the Santa Margarita River in Temecula. The Santa Margarita River flows through the "Gorge" and into San Diego County where it flows past Camp Pendleton into the Santa Margarita Lagoon at the Pacific Ocean. The Santa Margarita 'Region' is the portion of the Watershed that is within Riverside County. When it rains, the runoff from urbanized areas can collect pollutants which then can get transported into our regional receiving waters and can impair water quality and could cause harm to humans, plants and animals which depend on these waters. Urban runoff is one of the leading causes of water quality impairments in southern California today; the Santa Margarita Watershed Protection Program and its member agencies are working together to address this problem and help protect the quality of our receiving waters.

Member Agencies

The Riverside County Flood Control and Water Conservation District is the Principal Permittee of the Santa Margarita MS4 Permit.

Co-permittees: Murrieta Temecula Wildomar The County of Riverside

The Member Agencies listed above are named permittees on Order No. R9-2013-0001, as amended by R9-2015-0001 and R9-2015-0100 issued by the California Regional Water Quality Control Board, San Diego Region (Regional Board) on November 18th, 2015. Some of the requirements of this order became effective January 7th, 2016, and many new requirements will not be in effect until after the Regional Board approves the Co-Permittees compliance documents.

In the interim, the previous Order No. 2010-0016 is referenced. These permits outline programs and requirements that the Member Agencies must implement to comply with State and Federal Water Quality laws and to protect receiving waters from pollution. These requirements include the creation and implementation of plans to prevent the discharge of pollutants to the storm drain system and to our waterways, and annual report requirements. These plans and reports are provided below or are currently in the development process.

Compliance Documents

Benefit Assessment

Benefit Assessments are apportioned on the basis of proportionate stormwater runoff generated by each parcel. This method of assessment is consistent with State law and the District Act. The amount of benefit is computed based on parcel size (acreage) and use classification. The fee is referenced on property tax bills as "FLDCNTL Stormwater/ clean water".

For Questions Regarding the Stormwater Benefit Assessment Fees, please contact the District’s consultant: Webb and Associates, 1-800-439-6553.

Santa Margarita Watershed
Engineer's Report:
FY 19/20 FY 18/19 FY 17/18 FY 16/17 FY 15/16

Applications & Forms

Additional Resources

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