Lake Cachuma’s blue waters sparkle in the sunshine, but, invisible to the naked eye, the reservoir lake retains chemical contamination from last year’s Zaca Fire.

Area water agencies are — with the exception of the valley’s Santa Ynez River Water Conservation District — acting to blend their own wellwater with Lake Cachuma’s.

“First the fire came, and then the rain, and we felt it really affected our water supply,” said Susan Thompson, water treatment superintendent at Santa Barbara’s Cater Water Treatment facility.                               

Michael Kanno, operations manager for the Goleta Water District, agreed: “Because of the Zaca Fire, lots of ash in the rains washed into Cachuma and left a lot of organic material in the water.”

The problem is compounded because chlorine is used to disinfect the water as it passes through the treatment plants. The chlorine collides with the byproduct of the ash and the result is carcinogenic, (or potentially cancer-causing) matter in the drinking water.

 

Santa Barbara and Goleta get a substantial portion of their drinking water from Cachuma, but the Santa Ynez Valley does not. This area is officially called the Santa Ynez River Water Conservation District, known as Improvement District Number 1, or ID No. 1. Its general manager is Chris Dahlstrom.

“The Santa Ynez River and Cachuma Lake are serving us well,” he said.

The way this seeming contradiction works is that I.D. No. 1 contracts to exchange its Cachuma water rights for state water rights, thereby avoiding the problems that beset Santa Barbara and Goleta.

“They’re on the other side of the hill,” Dahlstrom explained. “The water from Cachuma flows through a large pipe into their water treatment plants.”

“In the valley, the problem is avoided because “I.D. No. 1 exchanges Cachuma water for state water that is filtered and treated, so we don’t have to build an expensive filtration plant. We’ve been doing this since 1997.”

Meanwhile, Santa Barbara and Goleta continue to battle the unintended consequences of the Zaca conflagration, which began last July 4 and blackened a total of 240,207 acres.

 

The subsequent rains washed the ashes into Cachuma Lake and other bodies of water. And the ashes, according to Goleta’s Kanno, contained organic material that interacted with the disinfectant chlorine.

Kanno explained, “The amount was too high and we had to blend it with our wellwater when it got to Corona del Mar,” Goleta’s water treatment plant.

“We’re anticipating that we can stop blending toward the end of September,” he said. “It depends on how much chlorine has gone into the water and for how long. Temperature is an issue, because as the weather cools the levels will drop off.”

 

Manager Thompson of Santa Barbara’s Cater facility agreed: “We’re doing the best we can to cut down on organic materials. I’ve been in this business 30 years and this is the worst catastrophe I’ve ever seen. It doubled the total of organic chlorine disinfectant byproduct (the potential cancer-causing material).”

 “My normal chemical budget would have been $400,000 and it went to $1.3 million,” she said.

“The fire and the rain really affected our water supply.”