Salinas Dam (forming Santa Margarita Lake) was built in 1941 under a military directive to supply water to Camp San Luis Obispo to support training needs for the Army during World War II. Due to this, the dam does not have a Civil Works Authority nor is it authorized for any flood risk management purposes. Shortly after it was built, Camp San Luis Obispo was no longer an active military facility, and the military transferred ownership to the Army Corps of Engineers (USACE) in 1955. USACE subsequently leased the facility to the San Luis Obispo County Flood Control and Water Conservation District (District) to operate the dam to provide water supply for the City of San Luis Obispo (City). The City has existing water rights for 45,000 acre-feet of storage, however current storage capacity is 23,843 acre-feet because the gate in the spillway was not installed as planned during construction due to structural concerns (indicated by arrow). Transferring ownership and putting in the gate is identified as an opportunity for securing additional water supplies to address needs in San Luis Obispo County in the County-wide Master Water Report.
A USACE Disposition Study has been funded and is being coordinated by the Los Angeles office with the District and the City. If disposition to the District from the USACE is feasible, local ownership is intended to ensure long-term security of a critical local water supply and facilitate opportunities for additional supply to the Paso Robles Groundwater Basin, designated as in critical overdraft by the State. It is anticipated that funding partnerships would be sought to help with any costs associated with transferring the dam to local ownership and installing the gates for increased water supply.
Staff are currently coordinating with the USACE and the California Division of Safety of Dams (DSOD) to understand whether it is feasible to transfer the dam to the District, what the process would be and what technical, administrative and financial issues may need to be addressed.
The USACE completed a semi-quantitative risk assessment of the Salinas Dam in 2019 and have provisionally rated it a Dam Safety Action Classification System Level IV (Low Urgency).