Santa Ynez Reservoir Floating Cover Replacement Project

Project Background

The Santa Ynez Reservoir Floating Cover Replacement Project is part of LADWP's ongoing commitment to maintaining a safe, reliable, and high-quality drinking water supply for the City of Los Angeles. The current floating cover was installed in December 2011 and plays a critical role in maintaining water quality. The reservoir stores treated drinking water for distribution throughout the area.

Major tears were repaired in 2022 and early 2025. Pinholes discovered in 2025, during refilling, revealed potential compromises in the cover’s integrity. To ensure continuous water system reliability, LADWP is moving forward with the design and installation of a new floating cover.

Project Description

The project involves removing the existing cover and replacing it with a new floating cover and liner system. The project scope includes:

• Removal and disposal of the existing floating cover and liner system
• Installation of a new geomembrane liner and floating cover system designed to meet current water quality and performance standards.
• Upgrades to associated equipment and mechanical features, including venting, pumping, and access systems.
• Inspection, testing, and commissioning of the new system prior to returning the reservoir to service.

During construction, LADWP will take measures to mitigate potential disruptions in service. Once complete, the new cover will protect stored water from contamination, reduce evaporation, and enhance overall system reliability.

Santa Ynez Reservoir Fact Sheet: Drinking Water and Fire Safety

Santa Ynez Reservoir Cover Replacement Project Press Release

Construction Information

Construction is anticipated to begin in January 2026 and is expected to be completed by Fall 2026, depending on weather, site conditions, and material availability.

Typical work hours will be Monday through Friday, 7 a.m. to 9 p.m., and Saturdays, 8 a.m. to 6 p.m.

Nearby residents may notice increased activity and equipment movement during construction. LADWP and its contractors will implement mitigation controls to minimize impacts to the surrounding community.

For safety, the reservoir site will remain closed to public access during construction. No interruptions to water service are anticipated.

In the event of an emergency, LADWP is prepared to maintain a level of water service through added contingencies including tank connections, hose deployments and emergency support measures.

Planned Contingency Measures

• Having hoses and connections readily available to be installed on Sunset Boulevard in the event of a service disruption to Westgate Trunk Line.  
• Deploying six miles of hose with booster pumps to move water from Corbin Tank to Temescal Tank if there is a service disruption.
• Positioning emergency generators in the Palisades to keep critical water equipment running during a power outage.
• Increasing brush clearing around LADWP facilities to reduce fire risk and maintain operations during construction.
• Stationing water tankers in the community and at Stone Canyon Reservoir for additional water supply during construction.  
• Ensuring aerial firefighting water sources remain available, including the Santa Ynez heli-hydrant, Palisades Reservoir cistern, and additional supplies at the Encino and Stone Canyon open-air reservoirs. 

Project Schedule

January 2026 – December 2026

Region

Pacific Palisades

Traffic and Parking

All construction activities will occur entirely within LADWP property. No traffic or parking impacts are anticipated for the surrounding neighborhoods.

Temporary signage will be posted near the site entrance to identify active work areas, delivery access points, and construction personnel routes for safety awareness.

LADWP appreciates the community’s patience and cooperation as this critical infrastructure improvement is completed to ensure the continued safety, reliability, and quality of Los Angeles’ drinking water supply.

Contact Us

(818) 775-5566

[email protected]