NAPA (CBS SF) — A water main break was reported in Napa Tuesday evening, Napa police and sheriff’s officials said.

The break, which occurred in the area of Foster Road, was affecting water service to homes and businesses in the Napa and Yountville areas, a Napa County sheriff’s dispatcher said.

The break occurred in a 36-inch water transmission line from the Jamieson Canyon Water Treatment Plant. That transmission line delivers water to the entire city of Napa, according to city officials.

Crews worked through the night to isolate the break and make repairs. It was estimated that service would be completely restored to affected customers by late Wednesday morning.

KCBS’ Bob Melrose Reports:

Customers at higher elevations were expected to experience the greatest loss in pressure.

Dirt settling in the pipes was causing water at affected homes to appear brownish in color, officials said. Residents were asked not to contact 911 over the break or related changes in service.

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