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Underground Flow Equalization System

UFES Project Update – February 6, 2024

Underground Flow Equalization System Project Nears Completion

The Underground Flow Equalization System (UFES) Project is moving steadily towards an early 2024 completion. The excavation at the San Mateo County Event Center Site has been backfilled and graded. The City has also discontinued monitoring for vibration and groundwater levels near the site, with dust and noise monitoring anticipated to conclude in the near future – a sign of significant progress towards project completion. Potential violations and resulting risks from construction-related dust, noise, vibration, and groundwater level changes were a concern for many residents near the site at the start of construction; however, no significant construction-related concerns were observed during the monitoring timeframe.

The City’s contractor is beginning to demobilize from the site beginning with anticipated removal of the construction trailers in early February. Major traffic impacts related to the UFES project are nearing completion. Minor occasional traffic inconveniences will continue. as the street portion of the project makes significant progress towards completion.

The City anticipates that the UFES project in its entirety, including work at the San Mateo County Event Center, will conclude in the Spring of 2024. Once the project is complete, it will be able to reduce the sanitary sewer overflows that result from excessive rainfall, which the community may have witnessed during last year’s rainy season.

We thank you for your continued patience and cooperation as we make steady progress toward the completion of our sewer system improvements.

Approved work hours are as follows:
San Mateo County Event Center Site: 7 a.m. – 7 p.m.
Saratoga Drive: 7 a.m. – 5 p.m.
South Delaware Street: 7 a.m. – 5 p.m.

*Construction schedules and traffic patterns are subject to change.

UFES construction
Grading continues at the San Mateo Event Center Site (photo credit: Tom Williams, City of San Mateo)

Stay Connected with the UFES Project

The Clean Water Program’s UFES construction is well underway and we want to keep you informed. The team established multiple information channels for residents and business owners to stay connected.

  • Sign up for construction alerts (text the word UFES to 1-833-321-0231), email us at or call our hotline at 1-650-522-7250.
  • You can also visit our UFES project page to see project details and sign up for our e-newsletter. If you don’t want to opt in, but still want information, bookmark the link where we post our updates to the project website.