For the past two years, the San Francisco Public Utilities Commission's (SFPUC) Water Enterprise has been undertaking an assessment of Turner Dam and surrounding areas to ensure that the structure and the San Antonio reservoir which it impounds are in good working order. Turner Dam is a 195-foot-high earth embankment dam that was completed in 1965, and the reservoir serves as an important source of water for the SFPUC regional system.
In September 2024, SFPUC contractors deployed a remotely operated vehicle (ROV) equipped with cameras and sonar equipment to inspect the dam's outlets. These are the areas on the inside of the dam face where water is released either into the regional delivery system or into the watershed. The vehicle is operated from the shore and allows for video recording of areas that are otherwise not easily accessible.
SFPUC engineers will be able to use the information collected from the ROV to understand the condition of the outlets, the effect of water flows, and sedimentation that occur in the normal operation of the reservoir over many decades. The results of the overall investigation will help determine any necessary future upgrades to ensure the dam’s continued service at this key water storage facility.
It's also important to note that any time the SFPUC deploys a boat or other instrument such as an ROV in any reservoir, it undergoes a thorough cleaning process before and after to avoid potential biological cross-contamination. It's just one aspect of the SFPUC's commitment to ensuring the environmental integrity of our drinking water and the watersheds we all rely on.