By Kiet Do

UNION CITY (CBS SF) — Northbound Union City Boulevard was still shut down between Smith Street and Whipple Road Friday morning after a water main break flooded the street Thursday afternoon.

The road closure continues to cause delays for local residents and commuters traveling through the area.

Employees with PG&E were working on a gas main nearby when they broke the water line Thursday afternoon, according to Lauren Sugayan, a spokeswoman for Union City.

Hundreds of thousands of gallons of water flooded the road. Alameda County Water District workers were able to stop the flooding and worked overnight to start excavating the site to repair the water main.

“It’s a pretty straightforward repair. It just happens to be in a very challenging location,” said Robert Shaver general manager with the Alameda County Water District. “It is a challenging repair for our water district today.”

It’s a large water main at 14 inches in diameter. It is also eight feet underground and sits below the water table, which means the hole they’ve dug around it constantly fills up with water that must be pumped out.

Adding to the challenge is the fact that the water main is just steps away from an active railroad. Shaver says the repair job is the district’s highest priority right now.

“I’ve been at the water district 27 years. In terms of main breaks I’ve seen, this is probably in the top five,” said Shaver.

Sugayan said the affected area is the northbound lane closest to Smith Street.

“Commuters currently heading north on UCB should detour at Dyer Street, south of the road closure,” she said.

Authorities don’t have an estimate for when the repairs will be done and the road will reopen, but have said that tap water in the surrounding area is safe to consume.

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