Strasburg violated water rule
STRASBURG – The town violated a drinking water rule recently but officials say the situation does not pose a health threat.
Assistant Town Manager Jay McKinley explained Thursday that tests showed the amount of total trihalomethane in the town’s drinking water exceeded standards. Trihalomethane is a by-product created when chlorine is used during the water-treatment process. The situation can occur when drinking water sits in the system long enough for the chemical to form.
The Virginia Department of Health recently notified the town of the violation. Now the town must notify water customers and plan to do so via their monthly bill as well as in the newspaper.
The town routinely monitors the drinking water for contaminants. Testing results for Nov. 11 and Dec. 3 showed the system exceeded the maximum contaminant level for total trihalomethanes for 2015. The maximum contaminant level for total trihalomethanes is 80 parts per billion. The average level for the 2015 compliance period was 84 parts per billion. McKinley pointed out that the town exceeded the limit by 4 parts per billion.
Water users do not need to use an alternative supply, the town advises. Users with health concerns should consult a doctor. Town officials anticipate they will resolve the problem within the next several months.
The problem arises in the distribution system and not the treatment process, McKinley said.
“That’s a big distinction that some people aren’t picking up on,” McKinley said. “When we use chlorine to disinfect with, which is really the only good disinfection source we have that’s available to any water treatment facility in the United States, given time it just breaks down in the system so we’ve started looking at the system as far as the residency times in different areas.”
Town officials have decided to install tank mixers designed to keep the water moving and prevent it from stagnating.
“I don’t think there’s any concrete, scientific data saying this is going to hurt you over time,” McKinley said. “It’s just that they have found connections with long-term, chronic exposure to these particular chemicals.”
As McKinley explained, the situation does not pose an immediate risk. However, some people who drink water containing the by-product in excess of the maximum level might experience problems with their liver, kidneys or central nervous and might have an increased risk of cancer.
McKinley was quick to point out that Strasburg is not experiencing the same problem as Flint, Michigan, where high-levels of lead have been found in that city’s drinking water. McKinley said he and Chris Ritenour, superintendent of Strasburg’s water treatment plant speculated that Flint didn’t properly control the pH levels in the distribution system, which caused lead to leach out of the pipes. Coincidentally, Flint did experience a similar problem with the treatment by-product almost a year ago.
“This is the only violation for as far as I can remember,” McKinley said, adding that the town’s water quality reports are available on its website. “There’s no lead or any metals, anything of that nature.”
Strasburg’s water treatment plant went online in December 2014. But the town tested the distribution system before then.
Strasburg must collect one distribution system sample each quarter from two locations and analyze the water to determine the level of the by-product. The sample results are averaged with the previous three quarter averages to determine the location’s running, annual average level. Should the running, annual average for a location exceed the maximum containment level, the Virginia Department of Health, which issues the permit that allows the town to provide water, deems the provider out of compliance.
The health department notified the town that it had exceeded the level for trihalomethanes because tests showed samples at the 19 Signal Knob Drive location averaged 84 parts per billion.
The town will perform quarterly sampling of the drinking water for trihalomethanes as required. The town also is examining the water treatment process to eliminate and/or minimize the presence of materials that cause the by-product to form. Officials are looking at potentially adjusting the rates at which chemicals are added to the water during the treatment process; relocating points where they add chemicals; installing supplemental aeration or mixing systems in storage tanks; or modifying operational procedures to reduce the age of the water sitting in the system.
It will cost about $60,000 to install tank mixers, McKinley said. Additional sampling stations could cost $10,000-$15,000 each. The town should absorb the cost of the improvements and not pass it on to the customers, McKinley said.
Contact staff writer Alex Bridges at 540-465-5137 ext. 125, or firstname.lastname@example.org