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Underground Flow Equalization System

UFES Project Update – January 14, 2022

UFES Project Reaches Significant Milestone

The UFES project has reached a major construction milestone: Phase 5 has begun, overlapping with ongoing Phase 4 construction activities. Phase 5 activities include installation of the concrete base, walls, column, beams, and roof elements of the UFES structure at the San Mateo County Event Center site. Mechanical and electrical equipment and the new electrical building will be installed as well. Phase 4 consists of foundation micro-pile installation. During this phase, a network of foundation piles is being drilled to support the underground structure, ensure it stays in place during seismic events, and prevent uplift (floating) from the naturally high groundwater levels in the area. Approved work hours at the Event Center site are between 7 a.m. and 7 p.m. Monday through Friday. Increased truck traffic will continue to and from South Delaware Street.

Pipeline installation work continues along Saratoga Drive and has started along South Delaware Street. Approved work hours for both Saratoga Drive and South Delaware Street are between 7 a.m. and 5 p.m. Monday through Friday.

Traffic control measures remain in place. Signs are placed in specific areas to provide direction and ensure the safety of drivers.

*Construction schedules and traffic patterns are subject to change.

Visualization of underground structure development

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.