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Underground Flow Equalization System

UFES Project Update – May 8, 2023

UFES Project Reaches Important Milestone

The UFES project has continued to make great progress despite the recent wet weather conditions. As of April 27, 2023, all of the concrete pours necessary to build the main UFES structure at the San Mateo County Event Center Site are complete. Over 11,000 cubic yards of concrete have been poured at the Event Center site. 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. The majority of UFES-related pipeline work and resulting traffic impacts along South Delaware Street and Saratoga Drive are expected to be complete in Spring 2023; however, minor traffic inconveniences in this vicinity may continue through Summer 2023. Please watch for traffic signs, which are placed in specific areas to provide direction and ensure the safety of drivers.

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.

Photo of UFES Construction
Construction crews make progress on the poured concrete ceiling (deck); April 27, 2023. Photo taken looking east towards the Electrical Building. Photo credit: 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.