Tuesday California starts enforcing a stricter standard for the cancer-causing chemical chromium 6 in drinking water. The new regulation was three contentious years in the making, it’s the toughest in the nation, and it presents a challenge for many smaller water suppliers around the state.
The new standard requires that chromium 6 levels must be no more than 10 parts per billion – that’s about 10 drops of the chemical for an Olympic-sized swimming pool’s worth of water.
Industrial pollution has left varying amounts of chromium 6 in the water of a number of local cities.
The chemical also occurs naturally in serpentine and other kinds of rock. That threatens the water supply in some rural areas, such as Santa Barbara County’s Santa Ynez Water District, says the district’s Chris Dahlstrom, who adds that the new state regulations will require his team to take a number of expensive measures.
"We actually have to build blending stations and treatment plants to treat out any kind of chromium 6 above that 10 parts per billion," says Dahlstrom.
All of that will cost at least $25 million, according to Dahlstrom and district documents. But Santa Ynez has not yet finalized its construction plan. So Dahlstrom says as of Tuesday, his water district will have to stop pumping from its wells.
"Fifty percent of our water supplies are being curtailed simply because we don’t meet those new standards that are set," he says.
Water districts across the state will have to spend money to comply with the new chromium 6 regulations. Much of that cost will be passed on to ratepayers.