Offshore Desal Pump Platform Stabilization Project

The Offshore Desal Pump Platform Stabilization Project (Project) will provide added protection to the City’s two offshore intake pump structures that support the Charles E. Meyer Desalination Plant. The pump structures are located about half a mile offshore in approximately 35 feet of water just east of Stearn's Wharf. Beginning in October 2025, Pacific Maritime will arrive with a 270-foot-long barge named Ocean Protector loaded with necessary equipment and materials to complete the work.  The barge will be anchored over the Desal intake structures for approximately four weeks. 

The Desal offshore intake pump platforms were originally constructed in 1991 as part of the City’s original Charles E. Meyer Desalination Plant (Desal Plant). As part of the 2016 Desal Plant reactivation project, new pumps and screens were installed in the existing offshore ocean intake platforms to pump water onshore for the desalination treatment process. During the reactivation project, it was discovered that one of the platforms was suspended about 18 inches above the sea floor, leaving space beneath the structure. Temporary measures were implemented at that time to stabilize the structure; long-term reinforcements are necessary to address the risk of movement or collapse.

The Project will implement a permanent repair by removing the temporary measures, filling the void space, and placing large rocks around the perimeter of both structures to help prevent future scour.
 

Construction of the Project will commence in October 2025 and is anticipated to be completed by mid-November, depending on weather and ocean conditions.

Construction will take place seven days a week, from 7:00 a.m. to 5:30 p.m. Please expect construction noise from heavy equipment. The barge will be lit with downcast lighting at night for the construction workers who will remain on the barge for the duration of the Project.

As part of the City’s long-term commitment to a diverse water supply, this Project improves the condition and reliability of the offshore pumps that keep the Desal Plant running. By filling the void space under the structures and protecting the structures with rock, the intake pump platform structures will be more resilient against strong currents caused by storms and large swings in tides, thus preventing movement or damage to the structures that might interrupt operations. 

Water Supply Benefits

The Desal Plant produces three million gallons of drinking water per day, which is sufficient to meet the needs of about 30,000 City customers. Annually, this equates to approximately 3,125 acre-feet or ~30 percent of the City’s annual potable water demand.

The City has developed the most diverse water supply portfolio in the state and continues to make innovative investments in our treatment plants and distribution system that will serve the community well into the future.

Preparing for extreme weather events requires community preparation and continued investment in infrastructure. Whether the threat is floods, sea level rise, or droughts, the City continues to position itself to respond to a myriad of natural disasters. 

City staff obtained a Federal Emergency Management Agency (FEMA) grant under the Hazard Mitigation Grant Program in February 2020 for the design and construction of a permanent repair. FEMA is contributing approximately $4.1M towards the Project. The remaining costs are funded by a combination of City water rate revenue and the sale of water to the Montecito Water District, in the amount of $1.8M.

In May 2017, the Desal Plant returned to operation after nearly 16 years on standby mode. As part of the reactivation project, new pumps and screens were placed in the existing offshore ocean intake platforms to provide the seawater for the treatment plant. The platforms were constructed in 1991 when the Desal Plant was originally built. Not long after operations began, a series of major storms scoured the ocean floor beneath one of the platforms, leaving it suspended 18 inches above the ocean floor and vulnerable to damage. The piers used to secure the structure from horizontal movement were not designed to support the structure elevated off the ocean floor. In reviewing the original 1991 design drawings, it was noted that both structures were to have been installed with rock armoring. For reasons unknown, that rock armoring was not installed, which is necessary to prevent strong currents from moving the ocean sand out from under the platforms.

After discussing various options for repair with California Coastal Commission staff, the City was granted permission to move forward with the repair. The Offshore Desal Pump Platform Stabilization Project will stabilize both platforms by filling the void space under the structures and installing protective rock armor around the perimeter of each platform.

Visit the Charles E. Meyer Desalination Plant webpage.

The Ocean Provider is a 270-foot barge from Pacific Maritime (City’s contractor) that will hold Project supplies and staff throughout the Project duration.