When it rains in Ohio, runoff from farms carries fertilizer and manure into waterways that flow into Lake Erie.
The runoff contains phosphorous, which researchers think is linked to blooms of algae that can be harmful to humans and wildlife. The blooms can also disrupt tourism and contribute to dead zones in the lake.
Peter Richards at the National Center for Water Quality Research at Heidelberg University says much of the phosphorous runoff comes through the Maumee River basin in Northwest Ohio. The blooms were especially bad after heavy rainfall in 2011, he says, but it isn’t certain whether that will be the case this year.
RICHARDS: “As of April 14, the latest date that we have the data in place for, the loads from the Maumee River were just about equal to the average for the period 2000 to 2012. So neither particularly low nor particularly high. But it remains to be seen what will happen during the rest of the spring.”
The National Wildlife Federation says farmers should try to reduce fertilizer runoff voluntarily. But the federation's report also recommends state and federal regulations, such as tying mandatory conservation measures to participation in the federal crop insurance program.
The report also says that the problem could get worse if climate change leads to more rainfall in the winter and spring in Northwest Ohio.