EPA downplays dredging risk to Bay City water supply

Sediments from the Saginaw River migrate into Lake Huron's Saginaw Bay

Nearly a month after the onset of a navigational dredging project in the Saginaw River that some worry will send dioxin-contaminated sediments downstream toward the intakes for Bay City’s water supply, EPA officials responded to citizen concerns by announcing it would not test the water for the toxin.

“I can understand why people would be concerned,“ EPA Superfund manager Wendy Carney, said in a phone interview. “But there are a lot of issues out there. We as an agency need to consider all resources and where our priorities should be placed. There are a number of issues that people are concerned about.”

Carney said that despite a 1978 agency report that warns that the migration of dioxin from Dow Chemical’s Midland plant could endanger local water supplies, the agency had determined that the ongoing dredging project by the U.S. Army Corps of Engineers doesn’t show a “strong likelihood” of impacting the Bay City water intake.

Testing is not necessary, she said, because the Army Corps dredging project is separated from the municipal water intake by approximately 22 miles, prevailing winds tend to blow sediments away from the intake and recent tests by state environmental officials showed no dioxin at the Bay City water intake. This is important, she said, because it confirms that agency’s theory of the route by which dioxin landed sediments travel into Lake Huron’s Saginaw Bay.

State officials, while agreeing that the water supply is safe, dispute EPA’s claim that they’ve found no dioxin in the sediments near the intake.

Department of Environmental Quality spokesman Bob McCann said that a 2004 sample of sediments at the Bay City water intake showed dioxin at 26 parts per trillion.

Though this is considered a small amount of dioxin in this region where levels as high as 1.6 million ppt have been measured — it exceeds the level that would be required for clean up in other states. Washington state officials, for instance, have a threshold level of 11 ppt for dioxin.

Labs that screen water samples for dioxin estimate the cost of a dioxin test at between $200 and $400.

In addition to overlooking Michigan Department of Environmental Quality data about dioxin near the water intake, Carney of the EPA overstated the distance between the dredging project and the water intake when she estimated the project was 22 miles away.

Saginaw County Public Works Commissioner Jim Koski is closely involved with the dredging operation and he estimates that this year’s dredging will come much closer to the bay. Bay City’s water intake is 6.5 miles from the mouth of the river.

“4.7 miles to the mouth of the river is as close as they will get this year,” Koski said, and he added that based on recent onsite observation of the project that “[i]t is stirring up some stuff on the bottom.”

EPA’s slow response and their decision not to monitor Bay City’s water disturbed Kathy Henry who wrote multiple letters imploring officials to sample the water.

“It seems apparent to me that US EPA is going all out to try and rationalize why they do not need to test municipal drinking water in the Saginaw Bay watershed when it really wouldn’t be all that difficult or costly. The results could be though.”