Newsletter – Summer 2026
The Clean Water Program is a comprehensive plan to upgrade the aging wastewater collection and treatment system with advanced infrastructure that will provide reliable services for years to come to 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, while some are either in design or construction.
The Clean Water Program has constructed a new wastewater treatment plant and underground flow equalization system facility and has made improvements to the sewer pipes and pump stations to improve the capacity of the system. These improvements align with the City’s sustainability goals.
This newsletter includes updates about active CWP projects. Detailed information can be found on our website.
Para información en español, haga el favor de llamar al (650) 522-7298.
Wastewater Treatment Plant Upgrades Near Full Completion!
The Wastewater Treatment Plant (WWTP) upgrade project will be fully operational in late 2026! Force main connections were completed early this year. The new plant is treating all the wastewater, and the old plant has been shut down.
Phase 3 is the final phase, and the last Phase 3 milestones include:
- Conversion of Existing Aeration Basins – August 2026
- Finish All Site Work – September 2026
- Project Closeout – October 2026
The WWTP is the most sustainable facility in the nation, serving San Mateo, Foster City, parts of Hillsboro and Belmont as well as Crystal Springs and a portion of San Mateo County. The plant produces the cleanest water discharged to the San Francisco Bay and is designed to withstand sea level rise. The plant protects public health and the environment by preventing sewer overflows during wet weather events, is designed to withstand storm surges and reduce greenhouse gases and carbon impacts. The project team secured $277M in low interest federal financing saving $20M in interest. The project includes walking and bike paths and public art. The Dale Avenue and Joinville Park walking paths are expected to be open in August 2026.
A small ribbon-cutting ceremony for local and elected officials and partnering agencies was held in September 2025. To view the WWTP ribbon cutting video click on WWTP video.
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.
Los Prados, Kehoe Kelly, and Arroyo Lift Station Rehabilitation Project Underway
The East San Mateo Lift Station Rehabilitation Project was kicked off with a public meeting in June 2025. Construction began in January 2026 and is expected to be completed in late 2027. The overall purpose of the project is to rehabilitate and replace existing aging sanitary sewer pump stations and significantly improve the reliability of transporting sanitary sewer flows in the City’s sewer system. This project involves:
- Installation of new pumps, wet wells, and emergency generators at three pump station sites
- Complete abandonment of an existing pump station site
- Replacement of more than 1,600 linear feet of existing gravity sewer pipe
- Installation of more than 4,000 linear feet of sanitary sewer force main pipe
- Reconfiguration of the S. Norfolk Street/Los Prados Street/La Selva Street intersection
Construction will typically take place Monday – Friday between 8 a.m. and 5 p.m. with some work after hours to accommodate high traffic areas. The project work will occur in three areas of the City as highlighted on the map, and started with the Los Prados area in mid-January 2026.
Residents in affected areas will receive notification ahead of construction in their area. Details about specific streets affected in each work area can be found on our project page.
For questions or more information, please contact: Laura Webb at 650.522.7322 or LWebb@CityofSanMateo.org.
El Camino Real Sewer Capacity Improvements Project Nears Completion
Construction activities related to the El Camino Real (ECR) sewer capacity improvements were completed in April 2026. The ECR project included installation of approximately 7,800 linear feet of pipe, including new and upsized relief sewers and maintenance hole installations throughout the project area.
Street restoration work, primarily repaving or resurfacing affected sections of City streets and El Camino Real, as shown in the figure below, started in June 2026. Work will require approximately two weeks at each location and is expected to be completed in August 2026. Impacts may include temporary road and parking closures, temporary detours, and temporary driveway restrictions, as well as typical construction noise, vibration, dust, and construction vehicle traffic.
Construction will occur in three different areas of the City as shown in the figure and as listed below.
In general, work will occur weekdays between 8 a.m. and 5 p.m. Work on El Camino Real will be performed between 9 p.m. and 5 a.m. to minimize disruption to the community. Residents near the affected areas will receive door hangers with additional details prior to work occurring in their area.
Please visit El Camino Real Sewer Capacity Improvements for complete project details or contact Makarand Pendse, Project Manager, at 925.392.3726 or makarand.pendse@jacobs.com.
Sewer Rehabilitation Projects
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. Wastewater from homes and businesses in San Mateo is collected via a network of pipes, maintenance holes, and pump stations. The collection system includes about 240 miles of pipelines, 6,000 maintenance holes, and 27 pump stations. This system transports wastewater to the Wastewater Treatment Plant for treatment and eventual discharge into the San Francisco Bay.
For more information about the Sewer Improvement Projects, please call (650) 727-6870 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.
B Basin (West Basin) Sewer Rehabilitation Construction Completed in March 2026
Basin B work occurred at multiple sites within the public right-of-way 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. Rehab construction began in April 2024 and was completed in March 2026.
Rehabilitation of the Basin B sewer included cleaning and CCTV inspection of:
- Approximately 200,000 linear feet of pipe in the public right-of-way
- Approximately 27,500 linear feet in easements on private property
- Approximately 800 maintenance holes in the public right-of-way and 130 maintenance holes in easements on private property
C Basin (East Basin) Construction Expected to be Completed July 2026
Basin C construction areas include parts 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. Westland Contractors began construction in February 2025 and plans to complete construction work in July 2026.
Basin C includes areas between J Hart Clinton Drive and Kimberley Way on the eastern side of Highway 101. Basin C is the collection system for public and commercial centers, including the Bridgepointe Shopping Center and the San Mateo Wastewater Treatment Plant, as well as several residential neighborhoods, including Shoreview, Parkside, Marina Lagoon, Marina Gardens, Lakeshore, Mariner’s Green, Harbor Town, and Laguna Vista. Basin C also includes repairs in a portion of El Camino Real from W. Santa Inez Ave to the Burlingame City limits. Notifications to residents and businesses two weeks prior to the start of work will continue in addition to notifications two to three days prior to starting work in the area.
Funds for repairs previously included in the upcoming El Camino Real & Large Diameter Sewer Rehabilitation project were allocated to the Basin C sewer rehabilitation project in October 2025 to allow work to be completed prior to Caltrans performing work in the same areas.
Cleaning and CCTV inspections of approximately 40,000 linear feet of pipe in the public right-of-way, 110,000 linear feet within easements on private property, and approximately 800 maintenance holes. CCTV inspections were completed in July 2023. The design process was completed in 2024.
D Basin (Central Basin) Sewer Rehabilitation Design Work Completed; Construction to Begin Late 2026
A construction contract will be awarded in September 2026 for the sewer rehabilitation in D Basin, which covers the 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.
The D Basin Sewer Rehabilitation project includes cleaning and video inspection of:
- Approximately 121,400 linear feet of pipe in the public right-of-way
- Approximately 84,000 linear feet in easements on private property
- Approximately 700 maintenance holes in the public right-of-way and 300 maintenance holes in easements on private property
Construction is expected to begin in October 2026 and is expected to be completed in January 2028. Notifications will continue to be mailed 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 the area if access to public maintenance easements is necessary.
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).
A Basin (North Basin) Sewer Rehabilitation Project CCTV Investigations Continue
The A Basin Sewer Rehabilitation project began CCTV investigations in July 2025, and they are scheduled to be completed at the end of June 2026. Detailed design work is expected to begin in July 2026. Notifications will continue to be mailed 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 the area if access to public maintenance easements is necessary.
Rehabilitation of the sewer 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 maintenance holes in the public right-of-way and 110 maintenance holes in easements on private property
Cracked sewer pipes and laterals, as well as faulty maintenance hole 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.
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 maintenance holes.
E Basin (South Basin) Sewer Rehabilitation Project CCTV Investigations to Begin Mid-2026
The E Basin Sewer Rehabilitation project is expected to begin CCTV investigations in mid-2026 and is scheduled to be completed in mid-2027. Notifications will be mailed 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 the area if access to public maintenance easements is necessary.
Rehabilitation of the sewer includes cleaning and CCTV inspection of:
- Approximately 212,067 linear feet of pipe in the public right-of-way
- Approximately 73,597 linear feet in easements on private property
- Approximately 1,083 maintenance holes in the public right-of-way and 311 maintenance holes in easements on private property
Cracked sewer pipes and laterals, as well as faulty maintenance hole 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.
Basin E covers the southwestern portion of San Mateo, west of El Camino Real, including the Beresford/Hillsdale, Westwood Knolls, Laurelwood, and Sugarloaf neighborhoods (see map). The purpose of the Basin E Sewer Rehabilitation Project is to repair and rehabilitate existing sanitary sewer pipelines and maintenance holes.
El Camino Real & Large Diameter Sewer Rehabilitation Design Work Continues; Construction to begin in Mid-2026
A construction contract will be awarded in late 2026 for the sewer rehabilitation of public mains in Caltrans Right of Ways (El Camino Real, Highway 92, Highway 101) and various larger diameter sewer mains throughout the City of San Mateo. Detailed design work began for the El Camino Real & Large Diameter project in November 2025, and the CCTV investigations were completed in October 2025.
Please visit El Camino Real Sewer Capacity Improvements for complete project details 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.
