Many San Luis Obispo residents have expressed concern about a recently mailed notice regarding a lapse in water quality standards in the city. Tests revealed levels of a chemical that exceeded Safe Drinking Water Act requirements.
The fliers, sent out by the Public Utilities Department, informed water customers about chemical compounds called trihalomethanes (TTHMs). The city said consumption of these compounds over a long period of time can lead to liver, kidney or central nervous system problems in addition to increased risk for cancer.
The state requirement is 80 parts-per-billion or less and city testing found that level had been exceeded with slightly more than 82 parts. Legally, the reading forced the publication as a notice.
Dean Furakawa is the city's Water Treatment Plant Supervisor. He said this is not an immediate health risk, but understands the public's concern.
"I think the one thing we underestimated, if anything, was the response to this notification," Furakawa said. "It's the first notification of this type that we've ever have to do, at least in my career ."
Furakawa said they found it difficult to get out the message required by regulators without overly alarming the public. He said just about every public water system in the nation has varying levels of TTHMs . The compounds form when chlorine comes in contact with organic material.
The longer the water is in the pipes, the more compounds are formed. Furakawa said the drought is actually making the problem worse because not as much water is moving through the system. There are also more organic material in reservoirs because of lower lake levels.
Simple carbon water filters—like Brita or Pur—will filter out some of these compounds.
Currently, the city is researching options to correct the problem, according to the notification.