1,4-dioxane fact sheet and frequently asked questions available

Thank you for subscribing to the City of Ann Arbor for website updates. A 1,4-dioxane fact sheet, frequently asked questions and water quality test results have recently been added and are available online at www.a2gov.org/A2H2O or via the link below:

https://www.a2gov.org/departments/water-treatment/Pages/default.aspxhttp://www.a2gov.org/departments/systems-planning/planning-areas/climate-sustainability/pls/Pages/pls.aspx

In February, one of the water treatment plant lab tests, sampled on Feb. 6, indicated an almost undetectable amount of 1,4-dioxane in the city’s surface water supply (Huron River) and in the finished drinking water. The results estimated concentrations of 0.061 parts per billion (ppb) of 1,4-dioxane at the city’s intake in Barton Pond and 0.030 ppb in the finished drinking water. Even though the amount of 1,4-dioxane isn’t even close to any EPA risk levels and our drinking water remains safe to drink, we believe it’s important to let you know of this first time detection. 

With recent advances in lab testing techniques, we are able to detect very low levels of contaminants in water samples. The presence of small amounts of contaminants does not necessarily indicate that water poses a health risk. The virtually undetectable levels in Ann Arbor’s drinking water were lower than the lab quantification limit and we are committed to investigating the cause. So, again in March, we will test for 1,4-dioxane, this time using two independent water-quality labs to see if any 1,4-dioxane is detectable.

The number one focus of the city’s drinking water staff is to protect public health; and we take this responsibility very seriously. The city is actively monitoring the situation and will provide updates when new information is available.