OAKLAND – The San Francisco Bay Regional Water Quality Control Board has approved a $5,557,700 settlement with Delta Diablo, a wastewater treatment agency serving eastern Contra Costa County, in connection with a sewage spill that released more than 23 million gallons of untreated wastewater into marshland connected to Suisun Bay.
The spill began around Nov. 5, 2024, and continued for nearly a month before being discovered on Dec. 2. It originated from a subsurface break in the Shore Acres Force Main beneath a marsh, which delayed detection. Delta Diablo repaired a 20-foot section of the pipeline within two days, stopping the discharge by Dec. 4.
“Sewage spills of this magnitude pose serious risks to water quality, wildlife habitat, and public health,” said Eileen White, executive officer of the San Francisco Bay Water Board. “This settlement holds the discharger accountable while making critical investments to modernize infrastructure and reduce the risk of future spills.”
Sewage spills can introduce harmful bacteria and pollutants into waterways, posing risks to public health, recreation and wildlife habitat. This incident underscores the importance of continuous monitoring, regular inspections and proactive maintenance of wastewater infrastructure.
Most of the settlement funds will be used to install a new force main parallel to the existing pipeline at the Shore Acres Pump Station. This upgrade will allow for replacement of the aging pipe while adding redundancy and increasing operational flexibility.
Additional funds will support improvements at Delta Diablo’s wastewater treatment plant, including retrofitting the discharge outfall with “duckbill” check valves. These upgrades are expected to improve effluent mixing, reduce sediment and aquatic organism capture, and prevent flow reversal at the outfall
The regional water board calculated the penalty in accordance with the State Water Resources Control Board’s Water Quality Enforcement Policy. Factors considered included the volume of the spill, the discharger’s response and corrective actions, and the potential impacts to water quality and beneficial uses.
This $5.6 million administrative civil liability is the largest penalty ever approved by the regional water board.
More information about the regional board’s enforcement actions can be found here.
The San Francisco Bay Regional Water Quality Control Board works to preserve, enhance, and restore California’s water resources to protect public health, the environment, and beneficial uses for current and future generations.
Delta Diablo Finalizes Settlement Agreement with Regulators following Sewer Spill in Shore Acres
Board of Directors Comments The District’s Board of Directors includes Monica Wilson, Chair (Antioch City Councilmember), Jelani Killings, Vice Chair (Pittsburg City Councilmember), Shanelle Scales-Preston,
Secretary (Contra Costa County Supervisor, District 5 [includes Bay Point]).
“Although this was a very challenging event in the District’s history, we are proud of the excellent response actions by our dedicated staff members once the SSO was identified—48 hours to repair the broken sewer line,
using above and beyond measures to reduce the SSO volume, and fulfilling all regulatory reporting requirements in a thorough manner,” said Board Chair Monica Wilson.
Director Scales-Preston added, “In representing Bay Point on the Board, I really appreciate the Regional Board’s support for allowing the majority of the regulatory penalty to be used for a project that will provide a
backup sewer line to ensure something like this does not happen in the Shore Acres community again.”
“Since joining the Board nine months ago, I would like to reassure the public that our staff is very focused on addressing aging infrastructure and proactively preventing outcomes like this in the future. Our core mission is
to protect public health and the environment, and our team takes that responsibility to heart,” said Board Vice Chair Jelani Killings.
Additional Information On December 2, 2024, the District identified a subsurface break in the 0.9-mile, 16-inch discharge forcemain from its Shore Acres Pump Station (SAPS) in Bay Point, which was causing an
SSO in a marshland area on private property owned by Military Ocean Terminal Concord and adjacent to a natural drainage channel running north from the SSO location to Suisun Bay. The District completed emergency
construction repair activities within 48 hours without any service disruption to customers. Following SSO identification, the District conducted extensive receiving water quality monitoring and spill impact assessments,
which did not identify physical evidence of gross pollution or impacts to aquatic life, wildlife, or vegetation.
The District is currently implementing a capital project to replace the existing 0.9-mile SAPS forcemain with a new primary forcemain and a backup forcemain that will be funded by the District under the Stipulated Order.
About Delta Diablo
Delta Diablo is a California special district that provides wastewater conveyance and treatment, recycled water production and distribution, renewable energy production, pollution prevention, street sweeping, and household hazardous waste collection services to over 218,000 customers in the Antioch, Pittsburg, and Bay Point. As a progressive “Utility of the Future,” the District embraces innovative approaches, sustainable solutions, and community engagement in achieving its core mission of protecting public health and the environment, while maintaining reasonable rates and serving as responsible stewards of the public’s resources and trust