The Impact of Ag: More Than Half of U.S. Rivers in ‘Poor’ Condition

It may look pretty, but odds are it's barely for for aquatic life. Photo: US EPA
It may look pretty, but odds are it’s barely fit for aquatic life. Photo: US EPA

Last Tuesday, the United States’ Environmental Protection Agency released the results of a comprehensive study that measured the vital signs of 1.2 million miles of American rivers and streams. The prognosis wasn’t great. Measuring things like water clarity, nutrient pollution, bacteria levels and mercury contamination, the EPA found that 55% of the river miles studied were in poor condition to support aquatic life like insects, crayfish and fish.
While the magnitude of the problem is sobering, the chief culprit wasn’t shocking for researchers here at the Center for Limnology.
“Most of the pollution is soil, manure and fertilizer running off of farm fields,” says CFL director, Steve Carpenter.
Specifically, it’s the phosphorous contained in that runoff. And it was, by far, the biggest problem with river water quality. Phosphorous is notorious around these parts as the main catalyst of harmful algal blooms in Wisconsin lakes and it gets into our lakes via Wisconsin streams.
“On Friday I took a long hike through the headwaters of the Blue River to look at
several feeder streams,” says Carpenter. “The streams draining plowed fields were dark chocolate brown, thick with mud. The streams draining well-managed pastures and wetlands were crystal clear.”
Wisconsin's Blue River. Photo: Trout Unlimited
Wisconsin’s Blue River. Photo: Trout Unlimited

Unfortunately, Carpenter notes, the high price corn now commands is leading many farmers to increase production and maximize yield by planting their fields right up to stream edges and culverts, often removing buffer zones they’d planted in times of lower prices.
“We need more cover crops and wider buffers along streams, even the small seasonal streams that run only in the springtime,” says Carpenter. “Anyone who puts on a pair of boots and takes a muddy walk in the headwaters can see it with their own eyes.”
But what’s less clear, says CFL faculty member, Emily Stanley, is what the report means as a whole.
Yes, American rivers were once so polluted they could catch fire. Archival Photo: Associated Press
Yes, American rivers were once so polluted they could catch fire. Archival Photo: Associated Press

“Comparing apples to apples, the percent of “good quality” streams declined over a 5-year period (the EPA conducted a similar stream study in 2004) which … is a little depressing,” she says. “But what we don’t know is how things have changed since the Clean Water Act went into effect over 30 years ago.” For example, she says, “We don’t have rivers that can catch fire like the Cuyahoga anymore, and there are a lot of other examples of individual rivers where things are much better.”
Not knowing how results in a similar study in 1983, for example, might differ from those in a 2013 study, means we don’t really know if our rivers are getting better or worse over the long run.
The Kinnickinnic River in Milwaukee is almost entirely channelized (encased in concrete). The city of Milwaukee is working to restore the river bank and design a more natural flow to reduce stormwater flood events and pollution. Photo: Adam Hinterthuer
Even today, the Kinnickinnic River in Milwaukee is almost entirely channelized (encased in concrete). The city of Milwaukee is working to restore the river bank and design a more natural flow to reduce stormwater flood events and pollution. Photo: Adam Hinterthuer

Still, it’s safe to say they could be better. And managing the flow of pollutants and nutrients into our waterways would go a long way to cleaning things up. The Clean Water Act took care of most of the “smoking pipes,” or instances where a single company was discharging industrial chemicals into a waterway or a city was letting its sewage flow downstream.
Today we’re fighting the tide of “no-point source pollutants,” each little stream of manure from fields, or oil from a parking lot or sediment from a construction site, adding up to a big mess for our rivers, lakes and stream – one we’re hopefully on our way to cleaning up.