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 | Polluted waters: A long and costly cleanup | |
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| The Whitewater River in southeastern Minnesota is under threat from a variety of pollutants, including runoff from nearby farm fields and leaky septic systems. (MPR Photo/Dan Olson) |
The Whitewater River faces another threat -- it's contaminated with a host of farm chemicals, including the weed killer atrazine. Environmentalists want atrazine officially listed as another pollutant.
Altura, Minn. — The Whitewater appears to be a picture-perfect river. The gin-clear water in its three branches courses gently through rolling farm fields and pastures, and then tumbles into glades of hardwood trees. The Whitewater's pools are home to trout, making the branches some of the state's most popular trout fishing territory.
But all is not well with the Whitewater. Pollution is taking a toll.
The middle branch of the river is one of the state's most closely watched bodies of water. The man in charge of monitoring the river takes a trek to view the device that collects water samples.
Paul Wotzka is a hydrologist with the Minnesota Department of Agriculture. Wearing a t-shirt and blue jeans, he threads his tall, lean frame through brush to the testing station.
The monitor isn't much to look at. It's a couple of boxes, some cable and conduit, topped with a small solar collector attached to a battery that powers the gizmo day and night. But high-tech magic pulses through the monitor's circuitry.
Wotzka no longer has to watch for rainstorms and then race to the river when one arrives, so he can grab water samples by hand. The automated monitor is always on duty. It's taken the guesswork out of wondering when and how often high water levels, or hydrographs, occur.
"We can have a storm hydrograph over and done with in a day, and typically those storms will start at about four or five o'clock, about the time everyone is going home. How do we catch those storms in the middle of the night? With this type of equipment," Wotzka says.
Wotzka has collected 12 years of Whitewater River samples. He sends them off to test for atrazine and more than two dozen other chemicals. The trend, he says, is clear. Levels of atrazine the past five years have steadily risen.
"What we see in those storm events is atrazine is about 100-fold higher than during the base flow conditions," Wotzka says.
The river at base flow carries about .5 parts of atrazine per billion parts of water. The level surges to 30 parts per billion during and after storms, well above the legal limit of three parts per billion.
Atrazine levels in the Whitewater peak sharply at the beginning of the growing season, when farmers spray the herbicide to control weeds in their corn and soybean fields.
A ride with Paul Wotzka shows that nearly all the farm fields along a stretch of the Whitewater's middle branch are planted with row crops.
The old days of a four-crop rotation, from corn to soybeans to small grains to alfalfa, are nearly gone. Some argue four, even three-year crop rotations slow rainwater runoff and help prevent pollution.
"You can see the corn, you can see some of the forage crops, you can see a field of soybeans over here," Wotzka points out along the road.
Planting corn or soybeans every year can mean more money for farmers pressed by rising costs and declining prices.
An added incentive is the federal farm program guarantees a base price for corn and soybeans, but not for other crops. But continuous row-cropping every year leaves more of the soil exposed longer, and that increases the rate of rainwater runoff. Young corn and soybean plants soak up some of the early growing season rains, but a large amount washes off the fields, carrying atrazine residue to streams and rivers.
Atrazine levels decline later in the growing season, as the larger thirsty plants soak up much more rainwater and when spraying for weeds has tapered off.
But atrazine doesn't go away altogether. It can take months for the herbicide to decompose. Research shows some of the chemicals left over when atrazine breaks down are an even greater risk to animal and human health.
Atrazine is made by the Swiss-based company Syngenta. Switzerland and most other European nations have banned the weed killer because of concerns over its effect on animal and human health.
Even so, atrazine remains one of the world's most popular herbicides. It's a very effective and affordable weed killer. Every year tens of millions of pounds are applied to crops around the globe.
Atrazine doesn't just kill plants growing among row crops. University of Minnesota environmental sciences professor Deborah Swackhamer says when the herbicide washes off farm fields, it also kills plants in lakes, rivers and streams.
"You might say,'Well, who cares if you've got more of this algae than that algae,' because that's the kind of tradeoff you get. But that can impact the food web, because higher order species depend on certain species of plants for their food. Just like we prefer certain plants to eat so does the aquatic food web," says Swackhamer.
Atrazine might be less of a concern if it latched onto soil particles and stayed in one place, but it doesn't. The herbicide and its byproducts migrate. They're being found in groundwater and in wells that supply drinking water.
Swackhamer says she wishes there were more studies of atrazine's impact on animal and human health, but she says there's little money to fund that kind of research.
For example, there's no clear evidence of atrazine's effect, if any, on fish in the Whitewater River, because it hasn't been studied. Laboratory tests link atrazine to irregularities in the reproductive cycle of female rats.
As for human health, two small studies, one in Iowa and another in Missouri, found low sperm counts in farmers who spray their fields with atrazine and in men who work as farm chemical applicators.
A good share of the attention atrazine gets in the media is the herbicide's effect on frogs.
University of California Berkley biology professor Tyrone Hayes says his tests show very low levels of atrazine, as low as .1 part per billion, cause changes in male frogs.
"These males might grow ovaries, these males might actually begin to produce eggs," says Hayes. "We also show that these males don't develop their voice box properly so they can't properly attract females."
Hayes says his new research, unpublished, shows an even stronger link between atrazine and effects on amphibian health.
Atrazine's manufacturer, Syngenta, disputes the findings and says other researchers have not been able to duplicate Haye's results.
Besides atrazine, southeastern Minnesota's Whitewater River has another pollution problem.
Thousands of springs burble throughout southeastern Minnesota and many feed the Whitewater. Before they reach the river, they slide through the region's unusual geology of fractured limestone. The springs pass through and under pastures and homes with failed septic systems.
Rainwater making its way to the springs carries animal and human waste containing fecal coliform bacteria that cause illness in humans.
Samples taken by the Minnesota Pollution Control Agency from the Whitewater River show levels of fecal coliform are routinely many times beyond the level allowed by law. The levels prompted the state to declare portions of the river's branches impaired or polluted.
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You shouldn't be swimming there, you shouldn't be wading there, you shouldn't fall out of your canoe. It's not safe.
- Kris Sigford, Minnesota Center for Environmental Advocacy
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"You shouldn't be swimming there, you shouldn't be wading there, you shouldn't fall out of your canoe. Direct primary contact is not recommended, not safe," says Kris Sigford, director of water programs for the Minnesota Center for Environmental Advocacy, the MCEA.
A check with state and local health department officials turn up no confirmed reports of human illness because of contact with the Whitewater.
State officials say they're taking steps to reduce fecal coliform pollution.
However, environmentalists also want the river listed as impaired for atrazine as well. That would be a first. No other body of water in Minnesota is listed as officially polluted because of a farm herbicide.
Environmentalists lobbied the Minnesota Pollution Control Agency two years for the designation. But state officials say the atrazine pollution isn't high enough and doesn't last long enough.
Current state standards require atrazine levels of more than 3.4 parts per billion be measured for 30 days during two different periods over three years.
State officials say levels much higher than the legal limit were recorded for one 30-day period last year. But the rules require another episode.
Environmentalists argue the levels have been high enough long enough.
The MCEA's legal director, attorney Janette Brimmer, says her group will consider legal action if the state doesn't cite atrazine as another reason for listing the Whitewater as impaired.
"Maybe PCA will agree. They may very well say, 'Yes, we agree it's finally tipped the scale.' But if not, we'll be taking a very hard look at it," says Brimmer.
The Minnesota Pollution Control Agency is not revealing ahead of time its revised list of impaired waters.
Environmentalists are pressing the issue in part because of the timing. The state is in the middle of revising its atrazine rules. The new rules will apply not just to the Whitewater but all of Minnesota's lakes, rivers and streams. Some groups want the state to lower allowable atrazine limits and others want them raised.
If the MCEA takes the state to court over the Whitewater's health, it wouldn't be the first time.
This summer a federal judge in St. Paul handed the group a major victory. The MCEA challenged how the state measures fecal coliform pollution. The judge agreed federal and state agencies were using a flawed formula and told them to revise it.
Dealing with pollution in the Whitewater River is one chapter in a long simmering legal and political tug of war over what to do about the declining health of Minnesota's lakes, rivers and streams.
Experts believe a very high number, perhaps as many as 40 percent of Minnesota's lakes and rivers are polluted. However, there's not enough money to monitor the waters, and lawmakers have so far been unsuccessful in agreeing on a way to pay for the testing.
Faye Sleeper, the MPCA's impaired waters supervisor, says only 8 percent of the state's rivers and only 14 percent of the lakes have been tested to see if they qualify for being on the impaired waters list.
"We have fallen behind. Currently we do not have the resources we need," says Sleeper. "The estimate is we need more than $81 million a year to do a more complete assessment, to do the studies, and then most of that funding would go into the actual cleanup activities."
State Rep. Dennis Ozment, R-Rosemount, chairs the House Environmental and Natural Resources Finance Committee. He says there'll be another attempt next session to fund a water testing and cleanup program. A bill he and others authored last session failed.
Besides money, Ozment says there's disagreement over what level of pollution is a risk.
"People take the information and they can kind of extrapolate out whatever logic or reason they want from that data, so it becomes very difficult to know what is really true," says Ozment.
The debate boils over when lawmakers propose ideas that threaten to take a bite out of the pocketbooks of farmers and agricultural interests.
State Sen. John Marty, DFL-Roseville, failed in his attempt last legislative session to ban the use of atrazine. He says he'd be satisfied with a partial ban, similar to what Wisconsin has done.
"We'd certainly like to first restrict it, ban it from the vulnerable areas where it's easiest to get into the surface water and the groundwater based on the type of soil and everything else," says Marty. "But in the long run, the fact that it slightly increases the corn production in Minnesota is not worth the environmental harm caused by it and the health risk caused by it."
There is agreement on other ideas for helping prevent further pollution of the Whitewater and other Minnesota waters.
One is grass buffer strips. Research shows the strips greatly reduce runoff. There's a federal program to help landowners pay for the strips.
The federal government this year is spending $3 billion on all of the country's soil and water conservation programs. About $150,000 has trickled down to Linda Dahl's agency, the Whitewater River Watershed Project.
Farmers and landowners in three counties served by the project can come to Dahl's office in Lewiston and apply for matching funds for conservation measures to slow runoff from their property.
"Could be a combination of grass waterways, contour buffer strips," says Dahl. "You could be looking at $10,000 to $20,000 in costs, and we offer 65 percent cost share."
Dahl says there are 650 farmers in her three-county area, and about 90 have signed on for various programs. Dahl believes many more would participate if there were more money or incentives.
A visit to Bill Reisdorf's dairy farm shows how the incentives work. Reisdorf's fields and pastures run along a stretch of the Whitewater River. He's using runoff control measures on his farm.
Reisdorf says the tight farm economy means most farmers will use conservation ideas only if there's money to help pay the cost.
"Farmers do respond to incentives. If what the public would like to have is cleaner water, then maybe they would be willing to subsidize and give us incentives," says Reisdorf.
The Whitewater River's middle branch slices through the center of Whitewater State Park, which gets about 300,000 visitors every years. The water rushes over a low dam built to create a small pond for swimmers. The park's recovery from an environmental disaster decades ago may contain lessons for how to solve the Whitewater's modern-day pollution problems.
In the mid-1800s, white settlers denuded southeastern Minnesota's densely forested hillsides and created farm fields. Then in the l930s, the rains stopped. The drought created the Dust Bowl across vast areas of the central portion of the country.
The organisms that acted like a glue to bind together the light soil particles in southeastern Minnesota dried out. Winds blew the soil off the fields. The silt literally buried homes, and families abandoned their farms.
When the rains resumed, water rushed across the barren fields into the river and choked it with sediment. The area became a kind of dead zone.
Recovery was painfully slow. Some of the abandoned farms became the basis for Whitewater State Park.
Conservationists made a living laboratory out of the environmental disaster. Their restoration experiments inspired creation of the federal Soil and Water Conservation Service.
Decades later there's little evidence of the calamity. Hillsides are shrouded with thick stands of hardwoods. A huge wildlife management area next to the state park is thick with trees, springs and marshlands.
Farming has returned, along with some of the old erosion problems -- and with the new pollution problems created in part by agriculture reliant on fertilizers and farm chemicals.
Minnesota Department of Agriculture hydrologist Paul Wotzka says the park visitors and anglers who love the Whitewater often stop him.
"They come up to me and say, 'What is happening to our streams, why is there so much silt in my favorite fishing hole, why does the stream smell when it has a storm hydrograph in it?"
More people are asking those questions, and wondering when solutions will be offered. They may get some answers when the state releases its revised list of impaired waters later this month.
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