Musty Water Due to Algae, Officials Say

Regional water officials scrambled Monday to assure sensitive-nosed residents from Beverly Hills to Thousand Oaks that the musty odor and taste they’ve noticed in their tap water for the last few days is a result of the heat wave and not biological terrorism.

Agencies supplied by the Metropolitan Water District of Southern California fielded several telephone calls in recent days from residents concerned that their water supply had been tampered with.

Officials said the smell and taste is caused by compounds produced by algae blooms in Castaic Lake in northern Los Angeles County, Lake Mathews in Riverside County and Lake Silverwood in San Bernardino County. Algae can thrive during hot weather, but the resulting compounds are not harmful to the public.

Reservoirs are being treated with copper sulfate, sprinkled from helicopters, to control the algae. But it could be weeks before the odd odor disappears. In the meantime, as many as 10 million residents and swimmers could be affected, although most people don’t have palates discerning enough to notice.

“Sensitive people will notice a difference in taste and odor,” said Don Kendall, general manager of the Calleguas Municipal Water District, which serves portions of Ventura County. “It’s strictly aesthetic. It’s perfectly safe to drink.”

Refrigerating drinking water diminishes the smell and taste, Kendall said.

This was the third such calm-the-public campaign that water agencies have announced since the terrorist attacks in September, and the second notification this month. Monday’s announcement covers swaths of Los Angeles and Ventura counties, including Beverly Hills, Burbank, Glendale, Santa Monica, Simi Valley, Thousand Oaks and Torrance.

Water agencies issued a similar announcement on July 3 to residents in Riverside, Orange and San Bernardino counties, and said Monday that residents in those areas can expect their water to remain slightly earthy smelling for several more days.

“Sept. 11 changed the perception of how we deal with taste or anything that might garner the attention of consumers,” said Metropolitan Water District spokesman Bob Muir.

“We want to be proactive about this in telling residents their water is safe.”