Tyler Water Utilities continues to improve drinking water quality, as testing results from ongoing monitoring show. The latest readings from all eight sampling sites are below the maximum contaminant level threshold of 60 parts per billion (ppb) for haloacetic acids.

After customers received notice of the exceedance of haloacetic acids in the drinking water last October, Mayor Martin Heines requested a third party evaluation of Tyler Water Utilities and its water treatment processes. Enprotec/Hibbs &Todd, Inc. (eHT) was hired by the City manager to conduct this review.

After physically inspecting Tyler’s two water treatment facilities, interviewing operations and maintenance staff, reviewing critical treatment processes, eHt representative Scott Hibbs reported that they found the facilities to be well maintained and effectively operated by Utilities staff. In their final report to the City of Tyler, eHt made several recommendations to reduce the formation of disinfection byproducts, some of which were completed immediately. Some remaining action items will be completed in the next several months as results from prior interventions are measured.

Very heavy rains last spring are believed to be the cause of the spike in haloacetic acids in Tyler’s drinking water last year. The run off from the rains brought excessive amounts of organic materials into the lakes that provide the water supply for Tyler. These organics reacted with the disinfectant used to eliminate harmful organisms in the water, resulting in the increase in disinfectant byproducts.

“Clearly, the improvements we’re making are working,” said Mayor Heines. “Even in the face of heavy rains earlier this year, we did not experience the peaks in haloacetic acids that we did last year and all sampling locations are in compliance for each individual location.”

Tyler Water Utilities (TWU) has made several process changes to improve its water quality since November, including increasing the use of ozone, enhanced coagulation and the addition of sodium hydroxide in the water treatment process.

The increased utilization of ozone at the Lake Palestine Water Treatment Plant was a recommendation from eHT. Ozone is used to reduce precursor organics related to the formation of problematic disinfection byproducts. Additionally, it has improved water quality by reducing taste and odor-related complaints.

The second treatment strategy implemented is enhanced coagulation. This process, like ozone, is utilized to enhance the removal of precursor organics prior to the addition of disinfectants often associated with the production of regulated byproducts. The results thus far have been promising.

The third change made by the Utilities Department was the addition of sodium hydroxide feeding capabilities at the Lake Palestine Water Treatment Plant in November of last year. Sodium hydroxide is used primarily to improve water stability by increasing the pH and alkalinity of drinking water, thus reducing the potential for corrosivity. In response to these positive results at the Lake Palestine Water Treatment Plant, TWU completed similar modifications at its Golden Road Water Treatment Plant.

The most recent test results obtained from TCEQ showed all eight sampling locations were below the maximum contaminant level of 60 ppb with results ranging from 14 to 52. The locational running annual average is also compliant for all eight sampling sites.

“As always, TWU’s mission is to maintain the highest quality and safest drinking water for the residents of Tyler,” stated Gordon Mayer, interim managing director for utilities and public works.