Did the Midland flood stir up contaminants that could hurt wildlife?
The flood that was caused by heavy rains and the failure of two dams near Midland caused property damage far downstream. But the long term damage might be in the contamination of wildlife.
Paddling a kayak through the Shiawassee National Wildlife Refuge, you can see that it's been flooded. But, for the most part, that's OK. It's a flood plain. It's supposed to flood here rather than in cities downstream.
This refuge is a stopover for migratory birds.
The Cass, the Tittabawassee, the Flint, and the Shiawassee rivers all come together around this 10,000 acres.
“We probably, on average, get about fifty thousand waterfowl,” said Pam Repp, manager of the refuge. Most of those birds have already made the stop in the spring as they headed north.
“We have Canada geese, blue wing teal, green wing teal. We have a lot of wood ducks. Wood ducks do nest here. We support most of the flyway," Repp explained.
That flyway is the Eastern portion of the Mississippi flyway of birds migrating between the southern U.S. and Canada.
The main concerns about the flood are these:
First, the flood waters are preventing plants from growing. The seeds from those plants feed the birds when they travel south again.
The second concern is that the massive flood could stir up legacy contamination from the Dow chemical complex in Midland, the biggest concern being dioxins.
Under an agreement with the U.S. Environmental Protection Agency, some of the dioxin was removed. Some of it was capped with stone. The question is: did the flood damage some of those engineered caps?
“This flood event was in line with the sort of worst case scenario that engineers design for,” said Lisa Williams, a Branch Chief of Environmental Contaminants for the Fish and Wildlife Service.
“But yes, there's a possibility that some of those sediment caps were disturbed or some of the bank management areas suffered some erosion and Dow and EPA started their inspections of the banks,” she added.
After paddling a kayak through parts of the Cass River, the Shiawassee, and the Tittabawassee you can get a good view of Greenpoint at Shiawassee National Wildlife refuge. This strip of land is where the refuge has the most problems with chemicals dumping onto the land. Basically, it's 20 miles downstream on the Tittabawassee from the Dow chemical complex. For most of the 20th century, contaminants, particularly dioxins were dumped into the Tittabawassee.
“They accumulate in the body and they can cause problems primarily for reproduction,” said Lisa Williams, adding, “So you have reduced reproduction, you have poor hatching success in birds. You can have deformities in birds that are associated with dioxin exposure.”
Researchers been monitoring bird eggs and reproduction rates for decades from the Dow site all the way to the Saginaw Bay. They know by measuring the dioxin levels in an egg whether baby birds are likely to survive.
Michelle Hurd Riddick is with the environmental group Lone Tree Council based in Bay City. She says the concern about contaminants goes beyond wildlife.
“Those critters are taking up those contaminants and they're flying to other places, many of them are game birds and people are eating them. So, you know, it's just this constant, continual contamination of the food chain. And humans are in that food chain,” she explained.
Of course, some of the wildlife does not migrate to other areas, such as the local game and fish.
“And there are people, especially in the urban area, that subsistence fish at the end of the month. When their checks run out and they need protein, they need food, they will go down to the banks of the river and they will fish,” Hurd Riddick said.
There are advisories about fish consumption and eating game such as deer, turkey, and other wildlife. Often those advisories are misunderstood or ignored.
We don’t know whether the recent flood caused more problems by stirring up dioxins. We also don’t know whether flood waters washed other chemicals from different businesses.
Lisa Williams with the U.S. Fish and Wildlife Service says the state is taking soil samples to test for chemicals. Dow is also gathering samples.
“We will see," she said, adding, "There are data being collected. People are going to be evaluating this. People are going to be looking at this carefully over the next weeks, months, and then into next field season when we can look at contaminant concentrations in bird eggs, when we can look at the reproductive success of Birds in Saginaw Bay.”
Williams is hopeful that the dioxin cleanup and other remediation efforts over the past several years will mean less wildlife contamination than seen in past floods.