INTRO: Algae is killing Lake Erie. And it’s hurting the other Great Lakes too. Erie was declared dead in the 1970’s and the parallels are haunting now. Biologists met recently in Windsor to share research. But as Michigan Now’s Chris McCarus reports, they still don’t know how to get rid of the green slime on the water.
The last two summers have scared swimmers, boaters and fishermen. Fertilizer ran off of farms into The Maumee River at Toledo and the Detroit River carried fertilizer and pollution from factory pipes. Both contain phosphorous.
“It was kind of a perfect storm in 2011. High loads from the Maumee combined with less dilution from the Detroit River then a warm dry year following that.”
Dr. Joe DePinto works for the environmental research firm LimnoTech. He spoke at a 2 day workshop in Windsor. The 50 other scientists kept asking him why Lake Erie is filled with algae. A simplistic answer is that farmers and homeowners spread fertilizer so plants will grow from the soil. Fertilizer makes plants grow in water too.
“It’s a combination of things. The question is what can we control? Can we control zebra mussels? Can we control thermal effluence from the power plants?”
DePinto said the Fermi 2 Nuclear plant near Monroe makes the water nearby 5 degrees hotter. Algae likes heat.
“But the real thing we can control is the phosphorous load.”
No one wants green goop on the water. What’s worse is that it takes out the oxygen that fish need. Reduced oxygen is called hypoxia. Dr. Depinto says Lake Erie will never eliminate it. Scientists are also worried about climate change. Drought lowers lake levels and that cuts off oxygen too. But no one can control phosphorous if even the scientists aren’t sure where it is coming from.
“So can we make the same conclusions that agricultural input is really the major driver here for phosphorous even though we have half the load coming through the Detroit?”
That question makes scientists think that runoff from roads and parking lots in metro Detroit could be adding to the problem. Not just runoff from farmers fields. But let’s cover this part first.
According to Jeff Reutter of The Ohio State University, who attended the meeting, “The Detroit River brings in 80% of the water and 50% (of the amount of phosphorous). The Maumee River brings in 3% of the water and the other 50% of the load. The algae respond to concentration not load. The Maumee water comes in like soup.” This is why the water pouring in from Lake Huron is not a suspect like the Maumee River is.
Shawn McElmurry points to another source of phosphorous in the Great Lakes. McElmurray is a chemist and environmental engineer at Wayne State University. He’s also a jogger in the streets and sidewalks of his neighborhood.
“A lot of these fertilizers are things that are supposed to break down. So there will be a timed release fertilizer. So there will be little balls and they crunch when you run on them.”
Fertilizer is Professor McElmurry’s enemy… people spread it on their lawns to make them thick and green. He and his wife live in Royal Oak where she joins him jogging.
“Yeah she’s a social worker so she’s sympathetic to a lot of things but it gets repetitive because it happens so often. We’ll be out running and I’ll start groaning and she says ‘I know I know. They should have applied their fertilizer better.’ She doesn’t understand the science behind it but she understands the importance of those things.”
Homeowners are putting up to 20 times more fertilizer on their lawns than they need to. The grains or pellets travel to lakes, rivers and streams by the souls of shoes, car tires and the rain. Professor McElmurry is exasperated.
“My reaction is why is this person wasting their money?”
“This is something that is completely controllable. And too often this happens. That fertilizer stays on the surface. When it rains it goes straight into the storm drain. It’s not benefiting the homeowner. It’s only hurting the environment.”
The conference on Lake Erie was sponsored by the International Joint Commission. Dr. Jeff Reutter of the Ohio State University is hopeful.
“If we go back and we look at total loading to Lake Erie 1968-1969, we were 29,000 metric tons and our target was 11,000, that’s about a two-thirds reduction that we had to achieve at the time. And we did it and when we did it the lake became the walleye capital of the world. So it’s worth doing.”
The U.S. and Canada were able to cut down on phosphorous 40 years ago because they banned phosphates in household soaps. These days, there’s no big and obvious source to target.