MESA COUNTY, Colo.- In the last two weeks, De Beque residents were notified of unsafe levels of disinfection by-products in their water. The town’s water supply had exceeded Environmental Protection Agency regulation levels of Total Trihalomethane or TTHM.
The EPA says the running annual average of TTHM must not exceed 80 parts per billion (ppb) in any given water supply, but in De Beque it was found the running annual average had shot up to 83ppb after high quarterly samples in May and August. KREX 5/Fox 4 gained access to records from the town which found the levels in May were 123ppb and in August, 107ppb. The records indicated the town has not gone over a running annual average of 83 ppb in the last five years, however. But it has been found prolonged consumption of water with high TTHm levels over many years can cause problems with the liver, kidney, and may increase risk of getting cancer.
When the running annual average exceeds 80ppb, state and federal law require residents to be notified, which De Beque town officials did after discovering the issue on September 9. The town’s administrator says the town followed state rules in notifying residents by early October.
De Beque town officials provided KREX 5/Fox 4 with a report from early September showing TTHM levels sitting at 40ppb. De Beque’s town administrator says the levels have been brought back down due to better control of the temperature inside the town’s water plant with air conditioning units. The town reported the TTHM levels were high in May and August after an increase in temperature inside the plant.
Ute Water’s water treatment plant superintendent explains how TTHM forms during the treatment process. Ute Water is a major water utility in the Grand Valley.
“They’re formed any time you add chlorinated water to surface waters: creeks, reservoirs, the raw water sources that most public water systems regionally draw from,” said Ben Hoffman, Ute Water’s treatment plant superintendent.
Hoffman says it’s a delicate balancing act, using compounds like TTHM to keep the water you drink and use free of harmful bacteria and viruses but also making sure those levels of disinfection by-products don’t get too high. He says those levels can exceed regulation for a variety of reasons.
“The organic content in the raw water, the amount of chlorine that you add to the water. Temperature can play a big factor.”
De Beque’s water is sampled on a quarterly basis,and town officials expect the running annual average of TTHM will be back below the 80ppb threshold outlined by the EPA.
Ben Hoffman at Ute Water says, warmer months typically lead to higher TTHM levels in most places.
“If you look at any public water system who tests quarterly, you’re going to find third quarter samples which are generally the hottest water temperature in your system.”