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Underground Flow Equalization System

UFES Project Update – September 13, 2022

Progress Continues on UFES Project

The UFES project continues to make great progress! As of September 12, 2022, almost 7,000 cubic yards of concrete have been poured at the San Mateo County Event Center site. The walls of the underground concrete structure are nearing completion. This fall, the team will begin preparation work necessary ahead of a series of pours that will build the ceiling of the structure.

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.

Starting in early October, lane restrictions will be put in place along Saratoga Drive in the vicinity of the San Mateo County Event Center. Additional restrictions will be implemented in this area in mid-October.

The ongoing pipeline work along South Delaware Street will begin to ramp down this fall; several of the pits along Delaware Street will be backfilled and restored in segments during the coming months.

Please watch for traffic signs, which are placed in specific areas to provide direction and ensure the safety of drivers.

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 photo
Photo of UFES project (facing southeast) showing completed floor and progress on the vertical walls; August 31, 2022. 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.