City Works to Fight THMS in Water Supply
By Aaryn Valenzuela
City Council members Thursday approved funding for a chemical used to help lower THMS levels in our water. About four months ago, the water supply tested high for THMS or Trihalomethane and didn't meet state requirements.
At the city's Water Quality Laboratory, workers test daily for Chloride and Sulfate . They also monitor the ph level of the water, which helps control Trihalomethane levels.
It was about four months ago when the city's water tested above the allowable limit.Trialomethane is a compound that occurs naturally when organic materials like leaves, and tree limbs decay.
"If you think of the lake levels getting real low, and you see a lot of trees growing in them and the lake rises, all those trees decay," says Tymn Combest, the city's Water Quality Superintendent.
City workers have been using Sodium Hydroxide or "Caustic Soda" to control THM levels.
"Every surface plant in the U.S. pretty much has problems with THMS, and the organic in the water, so we have been monitoring the ph closer, and we are putting in a new Total Organic Carbon Analyzer. We are also monitoring are anemonia levels. Those are things we can do to control our THM levels."
The city's water is now in compliance, and has been since their last test in December.
Combest says they've also purchased a new machine to help monitor the THMS.
"The TOC Analyzer we ordered will help us monitor the total Organic Carbon coming in, also we are going to look at different areas of the plant, and look at areas where we can reduce Carbon, which results in a reduction of THMS."
Low lake levels at OH Ivie Reservoir, and other lakes were the reason for the high THM levels. He say that could happen again this summer if lake levels get low.
" If OH Ivie gets down to 10 percent again we expect to be fighting Trihelomethanes again, but we are getting better at fighting them, so i think now we can probably keep the THM levels under control."
THMS have been regulated by the state since the 1980s. Last year, was the first time ever the city was not in compliance.