LOS ALTOS (CBS SF) — Water providers in Los Altos have advised 40 households not to drink their water without boiling it because of contamination caused by a contractor hitting a water main and adjacent wastewater line, state water officials said Wednesday.

The advisory is for residents of Fallen Leaf Lane between Holt and Morton avenues, Penny Way, Lantis Lane and at 1691 and 1701 Holt Ave., California Water Service officials said.

Drinking water for those residents may have been exposed to fecal coliform and E. coli bacteria. For drinking, making ice, brushing teeth, washing dishes and preparing food, residents are advised to either boil their water before using it or to use bottled water.

The water is still safe to use for showering and bathing.

Once repairs are completed and the system has been flushed, Cal Water officials will notify neighborhood residents whether their water is safe. Test results should be ready by Thursday, officials said.

“We apologize for this inconvenience to our customers,” Cal Water district manager Ron Richardson said in a statement. “Protecting our customers’ health and safety is our highest priority.”

Customers using bottled water while the advisory is in effect can submit receipts for reimbursement by Cal Water. Anyone with questions can call Cal Water at (650) 917-0152.

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