Water customers in the East Bay, South Bay, the Peninsula, and in San Francisco may see some temporary cloudiness in their drinking water for the next couple of months, a San Francisco Public Utilities Commission spokeswoman said last week.
Beginning Dec. 28, some SFPUC customers may see tap water that appears cloudy or milky-white in color but is nevertheless perfectly safe to drink, spokeswoman Maureen Barry said.
The change in the water is due to tiny air bubbles caused when an increased rate of flow from the agency's Sunol Valley Water Treatment Plant allows air to be mixed into the water.
If the water is allowed to stand for a few minutes, the cloudiness will dissipate as the air bubbles rise to the surface and break apart.
Due to maintenance on the regional water system, SFPUC customers are receiving water from local reservoirs in the East Bay and Peninsula, not from the normal source: the Hetch Hetchy Reservoir in the Sierra Nevada.
The cloudiness is expected to dissipate when Hetch Hetchy supplies reach the Bay Area again after the completion of the work, which is scheduled to finish around Feb. 20.
Customers in Alameda and Santa Clara counties are most likely to see the cloudiness, according to Barry. As the water works its way through the system, up the Peninsula and into San Francisco, the air bubbles will not be as apparent, she said.
The SFPUC is emphasizing that the cloudy water is "nothing to cause concern," Barry said.
The water continues to meet all state and federal regulatory requirements for water quality.
She said the same thing has happened in recent years, and although the agency did not receive many calls about the cloudy water last year, "it could happen, so we didn't want to alarm anyone if it does over the holidays."