The City’s Water Plant was addressed to the Board of Alderman at the July 25 City Council Meeting.
Representatives, Chris Callow and George Hausdorf, were present from PeopleServices, Inc. to discuss issues at the water plant including explanation of a public notice to be released to inform their customers the water has had high levels of total trihalomethanes (TTHM), along with informing them need for a chemical water engineer study and requesting a new pump.
TTHM are a group of disinfection byproducts that form when chlorine compounds that are used to disinfect water react with other naturally occurring chemicals in the water.
Based on the available information, long term consumption of TTHM in drinking water above the MCL may increase the risk of certain types of cancer (e.g., bladder, colon, and rectal) and other adverse effects in some people.
Hausdorf stated, “Drinking one liter for 60 years everyday could increase a person’s risk for bladder cancer.” The degree of risk for these effects will depend on the TTHM level and the duration of exposure.
They are colorless, and will evaporate out of the water into the air. Hausdorf explained, “We have high levels of ammonia and manganese which requires high levels of chlorine to off-set.” There are four significant TTHM potentially found in disinfected drinking water and their combined concentration is referred to as total TTHM.
Callow stated, “The TTHM test in June of 2018 tested high and caused the water plant to do quarterly testing.” The Department of Natural resources maximum contaminate level (MCLs) of TTHM is 80 parts per billion (ppb) or micrograms per liter as an average. Callow reported, “The City’s level test results were recorded at an elevated 90 ppb average. Since the quarterly tests have come back high, letters will have to be sent out to the public.” Federal compliance with the MCL requires that the running annual average of four samples not exceed the MCL at each sampling location. According to City Clerk, Chris Ellison, the letters were scheduled to be mailed out on July 30. At the city council meeting, City Administrator, Jackie Pangborn, informed the council the public notice was required to be mailed out by July 17, but the City did not receive the letter until late in the week informing them of the required letter to be mailed out.
Hausdorf shared, “The Department of Natural resources is recommending a chemical water engineer study to find a solution for the high levels of TTHM. The estimate of the engineer cost is $25-30,000.” The engineer study will help PeopleService’s change the chemical process correctly.
Levels of TTHM generally increase in the summer months due to the warmer temperatures, but can also be affected by seasonal changes in source water quality or by changing amounts of disinfection added. Water systems often can experience temporary increases in TTHM due to short-term increases in chlorine disinfection. Chlorine disinfection increases can occur when there is a water main break, when water systems are under repair, or when there is a potential microbial problem or threat.
People may be exposed to TTHM in drinking water from ingestion (i.e., drinking the water and ingesting it in foods and/or ice prepared with the water). In addition, TTHM vaporize readily into the air so inhalation exposure to TTHM can be significant, especially when showering and bathing, as can exposure from absorption through the skin.
Consumption of water with TTHM levels somewhat above the MCL for limited durations, for example, while corrective actions are being taken to lower the levels, is not likely to significantly increase risks of adverse health effects for most people. Because some data indicate that disinfection byproducts may increase the risk of developmental effects, women who are pregnant or may become pregnant may wish to avoid consuming water containing TTHM and other disinfection byproducts exceeding the drinking water standard. There are no current studies to show any short-term dangers.
Hausdorf also requested permission for the city council to approve the purchase of two Flowrox pump for the amount of $3,520 each plus shipping costs. He stated, “The current two pumps we have are not able to the job, we are operating high on the curve. This pump may be expensive, but it is our best line of defense.” The reasoning for the two pumps explained Hausdorf, stating, “The Department of Natural Resources requires us to have a back-up. If we purchase the new pumps, this would allow us to be notified immediately compared to the four hours it takes currently. The new pump would have an alert system with it. After much discussion, the Board of Alderman voted to purchase one Flowrox pump with all in favor.