2021-09-28 Water Quality Update

DRINKING WATER QUALITY UPDATE
AUGUST HAA5 LEVEL MINOR EXCEEDENCE

The City & Borough of Wrangell (CBW) committed to monthly testing of the drinking water to better track the level of Haloacetic Acids (HAA5), which previously exceeded regulatory thresholds during late summer and fall of last year. The maximum allowable limit of HAA5 in the water is 60.0 ppb. Wrangell’s levels have been well below the regulatory limit until the most recent August sample. The CBW just received the August results and the HAA5 level is at 70.0 ppb (10.0 ppb above regulatory allowance). Wrangell is not alone in facing water quality challenges at this time. Other communities in the region are experiencing similar difficulties.

Wrangell’s “official” HAA5 level is based on an annual, running average called the Locational Running Annual Average (LRAA). The sample months are established by the Alaska Department of Environmental Conservation (ADEC). Wrangell takes official samples in February, May, August and November. Even though this month’s test result slightly exceeds the allowable maximum, the annual average, based on the four official, quarterly samples is within range at 50.0 ppb.

As a reminder, HAA5 (Haloacetic Acids), a type of disinfection byproduct, forms when any remaining organic material present in the finished water is combined with a disinfectant, such as chlorine. A disinfectant is used to inactivate any pathogens remaining from the treatment process, and to protect the water within the distribution system. EPA sets standards, allowable maximum contamination levels (MCLs), for these byproducts. The MCL for HAA5 is 60 parts per billion (ppb).

The CBW Water Department monitors the treatment process very closely and makes adjustments as often as possible to ensure clean, safe drinking water. The Borough will continue conducting extra, monthly testing every month, and results will be reported to the community. This is not an emergency. However, those individuals with concerns should consider filtering drinking water with a charcoal filter.

###

Contact: Kim Lane, Borough Clerk, clerk@wrangell.com