The Daly City Department of Water and Wastewater Resources began flushing out the city's water main distribution system on Monday, a process that is expected to last until December.
On Monday through Thursday from 8 a.m. to 5 p.m., water crews will flush out each of the city's 686 streets, which have been divided into eight zones for the project, water department director Patrick Sweetland said.
Crews will spend about an hour flushing each city street, which removes sediment and mineral deposits through the opening and closing of system valves. Water is expected to run down the street during that time, according to Sweetland.
He advised residents can expect possible discoloring in water entering household plumbing systems and should minimize their usage of water on the day their street is flushed.
The discolored water is not a health hazard and results from naturally occurring sediment and mineral deposits. Water should appear normal by the evening hours on the day of street flushing, he said.
When we're flushing, if anything gets stirred up (it should be) clear by early evening hours," Sweetland said. "It's only that one day that (residents) will be affected."
To lessen the impacts of potentially discolored water, residents are advised to initially run only cold water at the tap, preferably in a bathtub.
If discoloration is observed, water customers should let the cold water run for several additional minutes until it clears, Sweetland said.
Residents may also experience cloudy or milky water when opening and closing water valves, which are air bubbles and not hazardous.
If running cold water does not clear the problem after 10 minutes, residents should notify the water department at (650) 991-8200.
For a schedule of when each street will be flushed, call (650) 746-8342. Information about the water flushing program can also be obtained at the city's website, www.dalycity.org.