Jessica Mathews / news@whmi.com


State testing conducted over the weekend did not detect the presence of hexavalent chromium in the Huron River system downstream of a chemical release.

On Saturday, EGLE crews tested 55 locations throughout the river system from Barton Pond – where the city of Ann Arbor has a drinking water intake – upstream to Wixom. None of the 75 samples tested from those locations had detectable levels of either hexavalent chromium or total chromium.

Of 144 water samples collected throughout 42 river miles since the release, three came back with detections of hexavalent chromium – two detections in Milford’s Hubbell Pond and one in the middle of Kent Lake.

The Kent Lake detection, completed by lab analysis late Friday – was 5 parts per billion (ppb) – just at the detectable limit of 5 ppb.

The two Hubbell Pond detections were 11 and 9 parts per billion. All three were at or below values to protect aquatic life. Those limits are defined in the attached release.

Industrial chemicals were discharged to the sanitary sewer system from Tribar Manufacturing in Wixom on the weekend of July 30th and routed to the Wixom wastewater treatment facility. The wastewater discharges to Norton Creek, which flows into the Huron River system.

The liquid contained hexavalent chromium, a known carcinogen that can cause a number of adverse health effects through skin contact or inhalation.

Investigators are evaluating test results from wastewater solids that were sequestered at the Wixom Wastewater treatment plant that appear to have trapped chromium, including hexavalent chromium, and of a carbon filtration system at Tribar Manufacturing that may have trapped the hexavalent chromium before it was discharged to the wastewater plant. Tribar makes chrome-plated auto parts.

Until further notice, the state is recommending that people and pets avoid contact with the Huron River water between North Wixom Road in Oakland County and Kensington Road in Livingston County. That includes Norton Creek, Hubbell and Kent Lake.

As additional test results are received, the recommendation will be updated.