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Underground Flow Equalization System

UFES Project Update – March 30, 2023

Progress Continues on UFES Project

The UFES project has continued to make great progress despite the ongoing wet weather conditions. As of March 23, 2023, over 10,000 cubic yards of concrete have been poured at the San Mateo County Event Center site – that’s equivalent to approximately 20,000 tons of concrete! The floor and walls of the structure are complete, and the concrete pours for the ceiling (or “deck”) began earlier this month.

Construction continues on the nearby electrical building at the Event Center site and the diversion structure on South Delaware Street near the intersection with Saratoga Drive.

The ongoing pipeline work along South Delaware Street continues to ramp down; several of the pits are being backfilled and the road restored in segments. Please watch for traffic signs, which are placed in specific areas to provide direction and ensure the safety of drivers.

Pipeline work along South Delaware Street and Saratoga Drive is expected to be complete in Spring 2023. The City anticipates that the UFES project in its entirety, including work at the San Mateo County Event Center, will conclude by the end of 2023. 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 the recent storms.

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.

Aerial photo of UFES project site
Aerial view of UFES project (facing north) showing completed floor and walls, rebar framework to support the ceiling, and a portion of the poured ceiling; March 7, 2023. Photo credit: Wilson Meany

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.