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Underground Flow Equalization System

UFES Project Update – December 15, 2021

UFES Excavation at Event Center Site Complete; Micropile Installation Continues

Activities related to Phase Three excavation at the San Mateo County Event Center site are complete, and the City’s contractor is making steady progress on Phase Four of construction. Phase Four consists of foundation micro-pile installation. During this phase, a network of foundation piles are 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. Most of this work will occur in the excavated area below the ground surface. The City’s contractor is preparing to start Phase Five, which includes work on the UFES structure and electrical building, in Winter 2022. 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 is starting soon 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 UFES Phase 4 construction.Visualization of micropile installation work

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.