Water treatment options up for discussion

BY ERIC LINDBERG
DAILY SOUND STAFF WRITER

Santa Barbara city staff will present findings from a recent study of water treatment technologies to the City Council tomorrow to determine the best way to comply with upcoming federal water quality regulations.
The second phase of new Environmental Protection Agency regulations focused on restricting the allowable concentration of "disinfection byproducts," or DBPs, will become effective in July 2010. DBPs result from chemical bonds between chlorine — a common water disinfectant — and naturally occurring organic material in water.

EPA officials suspect that DBPs cause cancer in humans if consumed at high doses over a lifetime and instituted the DBP Rule, the first phase of which took effect in 2002.
In order to comply with the second phase, the water treatment process at the William B. Cater Water Treatment Plant, which provides drinking water for Santa Barbara, Montecito and Carpinteria, will need to be altered. A year-and-a-half-long study authorized by the Council in 2005 determined that ozonation and chloramination are two options for reducing trihalomethanes and haloacetic acids, the targeted DBPs, in local drinking water.
"Based on information now available, staff believes ozonation is a better alternative because it is a superior disinfectant and significantly improves the taste of water treated at Cater," city staff noted.
According to Southern California Edison's website, ozonation involves infusing water with ozone gas, which causes bacteria particles to coagulate, making them easier to filter out. The process is nontoxic, produces odorless and colorless water, works against the toughest bacteria and viruses, and reduces chemical costs, the website states.
Chloramine, on the other hand, is a disinfectant formed by mixing chlorine and ammonia, according to the EPA's website. The result is a weaker but more stable disinfectant than chlorine alone. Although it reduces the amount of DBPs, it does not eliminate them. Chloramine is also toxic to fish and amphibians at levels used for water treatment, and cannot be used for kidney dialysis.
City staff will return to the Council in the coming months with a design contract for necessary improvements at the Cater Water Treatment Plant. Montecito and Carpinteria Valley water districts will provide 39 percent of funding for those improvements.