The Canyon Regional Water Authority soon will begin adding small amounts of ammonia to Cibolo's drinking supply in an effort to eliminate recent contamination problems.
Jan. 18—The Canyon Regional Water Authority soon will begin adding small amounts of ammonia to Cibolo's drinking supply in an effort to eliminate recent contamination problems.
The change in the system's disinfecting process should take place in February, a result of high levels of trihalomethanes — a byproduct of the current chlorine disinfection method.
The high levels were detected in October, but because of an apparent mailing blunder at the Texas Commission on Environmental Quality, the problem was brought to the city's attention only a few days ago.
"They still haven't been able to get me a good enough answer on that," Cibolo Mayor Charles Ruppert said.
Water quality experts said the water poses no immediate risk. That's because health standards are based on the potential of causing one additional incident of cancer for every 10,000 people who drink a half-gallon a day for 70 years.
Nevertheless, the Schertz-Cibolo-Universal City School District has supplied its Cibolo students with bottled water since Wednesday, district spokesman James Schindler said.
The district will not continue the practice this week, but crews will work through the weekend installing carbon filters at the cafeterias of the Cibolo schools.
The district also sent home letters informing parents they can send bottled water to school with their children.
"All the water quality officials are saying that the water is safe, but we're doing this for peace of mind," Schindler said.
Trihalomethanes are compounds formed when chlorine mixes with naturally occurring organic matter in water. The contaminants can increase the risk of bladder, rectal and renal cancer.
The federal government has mandated that large utilities test for the substance since 2002, and smaller ones, such as Cibolo, since 2004. In that time, more than 160 Texas water systems have documented high levels. This includes New Braunfels, which successfully ended the problem with a plan similar to Canyon Regional's, said General Manager David Davenport.
Davenport said he wants to add the ammonia process to all systems Canyon Regional serves, but is fast-tracking Cibolo because of the situation.
Cibolo's third-quarter water quality tests put it over healthy limits for trihalomethanes, and the newly released fourth quarter results also were high.
Cibolo's water also failed fourth-quarter tests for haloacetic acids, another byproduct of the chlorinating process with similar potential health impacts, said Alicia Diehl, team leader of the agency's drinking water quality team.
Adding ammonia to the water should decrease haloacetic acids also, she said.
The state tried to notify Cibolo of the problem in October, but mailed the notice to a post office box the city hadn't used since at least August, Diehl said.
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© 2005, San Antonio Express-News. Distributed by Knight Ridder/Tribune Business News.
