Newsletter – Winter 2025
The Clean Water Program is a comprehensive plan to upgrade the aging wastewater collection and treatment system with advanced infrastructure that provides reliable services for years to come to several communities in the San Francisco Bay area, including the cities of San Mateo, Foster City, and portions of Hillsborough, Belmont, Crystal Springs County Sanitation District, and the County of San Mateo. Many of these improvements have been completed or are near completion.
The Clean Water Program has made improvements to the wastewater treatment plant, sewer collection pipes, pump stations, and has constructed a new underground flow equalization system facility to improve the capacity of the system. These improvements align with the City’s sustainability goals.
This newsletter includes updates on CWP projects that have been completed recently or are still active. Detailed information can be found on our website.
¿Preguntas? Para información en español, haga el favor de llamar al (650) 522-7298.
Wastewater Treatment Plant
Wastewater Treatment Plant Upgrade Project Update and Upcoming Milestones
The Wastewater Treatment Plant (WWTP) upgrade project continues to achieve important construction milestones and make significant progress. Phase 3 construction activities are nearly complete. The installation of the yard piping was completed except for connecting the existing force mains to the new headworks, which is scheduled for May 2025. We anticipate the new processes will be operational in August 2025.
Clean water testing has begun and is expected to be completed in July 2025. Over the next four months, we anticipate all remaining electrical and mechanical equipment to be installed in the new process areas. Electrical equipment installation in the Membrane Bioreactors (MBR) and Headworks electrical buildings has been completed. Chemical Area construction and storage tanks and associated pumping equipment installation has also been completed.
Warehouse construction is substantially complete, and a temporary occupancy occured in October 2024. The upgrades to the Sodium Bisulfite Tanks and transfer pumps are nearing completion. The upgrades to the existing Chlorine Contact Basins are completed.
Here is a brief summary of recent and upcoming Phase 3 plant construction milestones:
- Existing Plant Chemical Area Improvements – March 2025
- All New Processes Areas Completed – April 2025
- Clean Water Testing – January to July 2025
- Plant Seeding – June 2025
- Plant Performance Testing – July to August 2025
- New Processes Operational – August 2025
- Potential Ribbon Cutting Ceremony- September 2025
- Conversion of Existing Aeration Basins – July 2025 to Feb 2026
- Finish All Site Work– March 2026
- Project Closeout – March to April 2026
For more information about our exciting new WWTP, please visit our WWTP page. You can also e-mail info@CleanWaterProgramSanMateo.org, or call us at (650) 727-6870.
Underground Flow Equalization System
Underground Flow Equalization System Nearing Completion
Our Underground Flow Equalization System (UFES) is wrapping up the final phases of completion. Remaining work includes site cleanup, performance equipment testing, and some minor landscape work around the project areas. The major accomplishment of the project is the 5.3-million-gallon UFES structure beneath the parking lot of the San Mateo County Event Center. Other than a small operations building, the entire structure and associated equipment is underground. The system operated successfully during preliminary tests and is ready to minimize future sewer overflows.
We would like to extend our appreciation to our community for your continued patience and cooperation throughout the design and construction process.
For more detailed information about the UFES project, please visit our UFES page. You can also e-mail info@CleanWaterProgramSanMateo.org, or call the UFES hotline at (650) 727-6870.
El Camino Real Sewer Capacity Improvements Project almost Complete
A majority of the El Camino Real (ECR) Sewer Capacity Improvements Project was completed in October 2024. The remaining work involves a section of sewer installation work near Laurel Creek that got delayed due to unforeseen underground conditions. The project included installation of approximately 7,800 linear feet of pipe, including new and upsized relief sewers and manhole installations.
All construction work in Area 1 was completed and majority of work in Area 3 along, or adjacent to, El Camino Real was completed as shown in the figure. As noted above, some work remains in Area 2 along El Camino Real.
Please visit El Camino Real Sewer Capacity Improvements – Clean Water Program San Mateo for complete project details or contact Makarand Pendse, Project Manager, at 925.392.3726 or makarand.pendse@jacobs.com.
Dale Avenue Pump Station Project – New Generator Installation Nears Completion
The purpose of the new generator is to provide power supply to the pump station in the event of a power outage. The pump station is vital for the operation of the City’s sewer system and must remain operational 24/7. The construction of the foundation for the new emergency standby generator was completed in January 2025 and the installation of the generator is expected to be complete in March of 2025.
The City’s contractor, Anvil Builders, Inc., is scheduled to perform and complete start-up and testing at that time. Once the new generator is start up tested, the temporary generator will be moved away.
For more project information, please visit our Dale Avenue Pump Station page or contact CWP Project Manager Makarand Pendse at (925) 392-3726 or makarand.pendse@jacobs.com, or email info@CleanWaterProgramSanMateo.org.
Sewer Rehabilitation Projects
In San Mateo, wastewater from homes and businesses is collected via a network of pipes, manholes, and pump stations. The City collection system includes about 240 miles of pipelines, 6,000 manholes, and 27 pump stations. This system transports wastewater to the treatment plant for treatment and eventual discharge into the San Francisco Bay. The Sewer Rehabilitation Project consists of areas divided into five basins, identified as Basins A through E, which are part of the City of San Mateo’s rehabilitation of the overall wastewater collection system.
For more information about the Sewer Improvement Projects, please call (650) 727-6870, or email info@CleanWaterProgramSanMateo.org or contact CWP Project Manager Laura Webb at (650) 522-7322 or lwebb@cityofsanmateo.org.
¿Preguntas? Para información en español, haga el favor de llamar al (650) 522-7298.
E Basin (South Basin) Sewer Rehabilitation Project Construction is Complete
The Basin E project began construction in Fall 2023 and was completed in February 2025. Basin E includes the southern portion of the City, west of El Camino Real. The purpose of the E Basin Sewer Rehabilitation Project was to repair and rehabilitate existing sanitary sewer pipeline and manholes.
Basin E work included:
- Gravity Sewer System – Spot and segment repairs
- Manholes – Repairs and replacements
Contractors repaired damaged or displaced 6-, 8-, and 10-inch-diameter sanitary sewer mains with the same size pipe at 343 locations. Work also included rehabilitating 212 manholes with lining, repairing channels and benches, and fully removing and replacing select manholes. Common manhole rehabilitation methods include (1) replacing the frame and cover, and (2) applying cement mortar as a binding agent to the inside surfaces.
B Basin (West Basin) Sewer Rehabilitation Construction to be Completed Soon
Rehab construction began in April 2024 and is expected to be completed by June 2025. Basin B work is occurring at multiple sites within the public right-of-way (ROW) and within easements on private property, including front yards, backyards, and driveways. Basin B includes downtown San Mateo, and those City areas west of El Camino Real between Highway 92 and Crystal Springs Road. Basin B serves as the collection system for public and commercial centers, such as Downtown San Mateo as well as several residential neighborhoods.
Easement access notifications are being mailed to residents and businesses in the affected area prior to the start of work. The contractor will provide additional notices two to three days prior to work starting in specific areas of B Basin.
C Basin (East Basin) Design Completed and Construction Began February 2025
Basin C includes areas of the City east of Highway 101, between Foster City to the north and J Hart Clinton Drive to the north as shown on the map below. The design process for C Basin was completed in Summer 2024 and the project went through the construction bid process and was awarded to Westland Contractors, Inc. Construction is scheduled to begin in February 2025 and is estimated to be completed in February 2026.
Notifications will to be sent to residents and businesses prior to the start of work, and the contractor will provide additional notices two to three days prior to starting work in your area.
D Basin (Central Basin) Sewer Rehabilitation Expected to Be Underway Soon
D Basin covers San Mateo area south of State Route (SR) 92 and southwest of Highway 101, with a smaller portion extending to the north side of SR 92. Basin D serves as the collection system for public and commercial centers, such as the Peninsula Golf and Country Club and the San Mateo County Event Center, as well as several residential neighborhoods such as Hayward Park, Sunnybrae, Bay Meadows, Beresford Manor, San Mateo Village and Lauriedale (see map).
Detailed design work will be completed by Spring 2025. The project will go through the construction bid process at that time, and a contract is expected to be awarded by Summer 2025.
A Basin (North Basin) Sewer Rehabilitation Project to Begin CCTV Investigations Soon
Basin A covers the northern portion of San Mateo, including the North Central, North Shoreview, San Mateo Park, San Mateo Heights, and a portion of Baywood neighborhoods (see map). The purpose of the Basin A Sewer Rehabilitation Project is to repair and rehabilitate existing sanitary sewer pipelines and manholes.
The A Basin Sewer Rehabilitation project starting in Spring 2025 includes cleaning and CCTV inspection of:
- Approximately 190,050 linear feet of pipe in the public right-of-way
- Approximately 44, 450 linear feet in easements on private property
- Approximately 900 manholes in the public right-of-way and 110 manholes in easements on private property
Cracked sewer pipes and laterals, as well as faulty manhole covers, allow rainwater and groundwater to flow into the sewer system. Regular checks are needed to maintain the proper operation of the system, to meet regulatory requirements, and to prevent sewer overflows.
Notifications will to be sent to residents and businesses prior to the start of work, and the contractor will provide additional notices two to three days prior to starting work in your area if access to public utility easements is necessary.