Most of us can recognize pollution when it comes out of a sewer pipe or a smokestack. But it's harder to see - and control - the pollutants that run off our city streets, lawns and farm fields. Now new research at Ohio State University shows that the impact of those pollutants is changing as we change the way we use the land. And that's having an effect on Lake Erie. Yesterday a group of researchers assembled at Lorain County Community College in Elyria for a conference on the delicate balancing act between land use and water quality. ideastream's Karen Schaefer was there.
It's 1969 and the Cuyahoga River is on fire. Johnny Carson calls Lake Erie the place where fish go to die. Scientists discover that too much of the nutrient phosphorus is entering the lake, causing dead zones and fish kills. Congress passes the Clean Water Act to start the clean-up process.
Fast forward to 1990. Detergents with phosphorus have been banned and sewer treatment upgraded. Phosphorus is under control. The lake is cleaner and - with the coming of zebra mussels - clearer. Lake Erie is the walleye capital of the world.
Then, five years later, everything changes again.
Jeff Reutter: This has become very typical, essentially every summer since about 1995 or 1996. You can see a pretty good swig of blue-green algae coming in.
Dead zones begin to reappear. So do algae blooms. That's the state of the lake today. And scientists like Jeff Reutter, director of Ohio State University's Stone Lab Lake Erie research center, are stumped.
Jeff Reutter: The concentration of phosphorus within the lake has been increasing every year since 1995. And if the loading hasn't changed significantly, why are we seeing this increase in the concentration of phosphorus?
Researchers like Jeff Reutter and Elena Irwin, an economist at OSU's Department of Agriculture, don't know the answer to that question - yet. Part of the answer may lie with invading zebra mussels, part with global warming. But at least some the answer lies with the way we live on the land.
Elena Irwin: There are clear connections here between the lake and between people and what's going on on the land. There are clear connections, but understanding those connections is much more difficult.
Irwin is working on a research project to try to understand how regional patterns of economy and land use impact the lake - and how changes in the lake affect us. Using Landsat photos and geographic information systems, she's piecing together a new picture of how we live in the Lake Erie watershed. Pointing to a chart behind her, she says she's found some remarkable trends.
Elena Irwin: If you look at what's going on here, it's not just modest declines in population, but it's a really a reorganization of people across the landscape. The blue bar, small but growing significantly - for example, 12% growth in the '90's - is showing you the population growth in the unincorporated areas, the township areas.
Irwin believes the implications are staggering. People living in semi-rural areas no longer use sewer treatment plants, but rely on septic systems that leak into groundwater and streams. Add to that changes in agricultural use - fewer, bigger farms with more concentrated livestock operations - and she says you can begin to see why Lake Erie is feeling the impact.
Elena Irwin: I'm pessimistic about our ability to control development in coastal and watershed areas.
Jeff Reutter: To solve our dead zone issue we're going to need to make further reductions in phosphorus loading and that's going to be really hard to do.
But a glass that's half-empty is also one that's half-full. Researchers at the Lake Erie land use conference are urging regional planning as one way to limit sprawl. New tools have been developed to help local planners base land-use decisions on the impact to local watersheds, with grants available for planning. Farming practices like no-till agriculture, cover crops, and stream buffers are a proven way to help reduce run-off from fields and barns. Above all, researchers say educating everyone about how life on land affects life in Lake Erie will go a long way to making the region's most important natural resource a healthy asset on which to build a strong economic future. Karen Schaefer, 90.3.