Vanishing Point

Researchers say agriculture is killing Lake Pepin. Can a national treasure be saved before it’s too late?

Nineteen years ago, Michael McKay purchased a house in Wacouta Township, a few miles south of Red Wing, along the northwestern shore of Lake Pepin. A Minneapolis native, McKay had come to the area for work, but it wasn’t long before the city guy fell under the big lake’s spell.

Later, when a new job materialized in the Twin Cities, McKay chose a 90-minute commute to Shoreview rather than relinquish his idyll. “There was no way in hell I was going to move back,” he says. Instead of relocating his family, he remodeled his rambler, replacing every window in the house just so he could soak up the commanding views.

Standing on a ridge in his backyard, McKay, a fit-looking 59-year-old with silvering hair, surveys the head of the lake. At 30 miles long and three miles wide, Pepin is the largest lake on the Mississippi River and its scenery befits that distinction. McKay is quick to note the bald eagle circling overhead. Eagles are ubiquitous on Pepin. It’s a source of pride among locals (many of whom remember when the birds were scarce), and a selling point for the local tourism industry. The eagle population got a boost from the Prairie Island Nuclear Generating Plant, which discharges warm water into the Mississippi River at Red Wing. Even in January, the north end of Pepin, where the river enters the lake, is ice-free, allowing over-wintering eagles to fatten on fish.

McKay contemplates this interplay between man and the natural world. “It’s almost like the lake is one big living organism,” he muses.

A few years ago, however, McKay and his neighbors along Wacouta Bay began to notice signs that the “organism” was ailing. Some parts of Pepin seemed to be growing shallower, McKay says. It became difficult to cross the lake to favorite haunts on the Wisconsin side, even in a low-draft fishing boat or water scooter. A few river towns gave up dredging, making it difficult for locals to reach navigable parts of the lake.

Near the Mississippi inlet, McKay noticed, unfamiliar sand bars had emerged. Riparian vegetation had begun to spread, and new islands and peninsulas were forming. Examining aerial photographs, he noticed how the land mass around Wacouta Bay had expanded over the decades.

“You can see what’s happening,” McKay says flatly. “The lake is filling up.”

Mckay does not self-identify as an environmentalist. He has no background in water issues or conservation, and his current job, as general manager at the St. James Hotel in Red Wing, keeps him plenty busy. But last year, McKay and some of his neighbors from Wacouta Bay joined other Lake Pepin lovers from Minnesota and Wisconsin to form the Lake Pepin Legacy Alliance, a nonprofit citizens group urging stricter controls on erosion, the cause of the crisis. McKay was worried enough about the changes in Pepin that he decided not only to sign on with the group, but to serve as its executive director.

As part of that job, McKay has immersed himself in tracking the multi-agency governmental effort to address the problem. He has attended countless conferences (and hosted some) and pored over reams of Lake Pepin–related research (the subject of the biggest water-pollution study in state history).

The experience was an eye opener in the real-world convergence of science and public policy: “We wanted to find out what the hell was happening,” McKay says, a touch exasperated. “And we were shocked when we found out all the information that is out there—all that is known—and yet there’s no action.”

Indeed, the prognosis for Lake Pepin is grim. Using core samples extracted from the bottom of the lake, researchers have calculated the contemporary and historical volumes of sedimentation, the term for the in-filling caused by silt, clay, and other solids that are deposited in the lake by the Mississippi River. At the current rate, according to these estimates, the upper third of Pepin will mostly vanish within a century. Within 340 years, all of Pepin will be transformed into a muddy channel. Much of the life will be choked from the lake, experts say, because sunlight won’t penetrate the murky waters. Lacking healthy aquatic vegetation, what’s left of the lake will be largely bereft of fish, waterfowl, and, perhaps, even those iconic eagles. And without those treasures, tourism in the area could plunge.

The scenario is mind-boggling but, then again, so is the amount of muck flowing into Pepin. Imagine a dump truck emptying a 12-cubic-yard load into the lake every eight minutes, every hour, every day of the year, says Norman Senjem, the Mississippi River Basin coordinator for the Minnesota Pollution Control Agency. Or, if you prefer, picture a square city block, and then conjure a pile the height of the 32-story Foshay Tower. That’s how much sediment washes into Lake Pepin annually.

Senjem and the MPCA want to slow that landslide. The agency hopes to reduce the flow of suspended solids into Pepin by 50 percent. According to agency scientists, such a reduction would promote the growth of wild celery, an aquatic plant species that provides essential forage for waterfowl and ideal cover for fish.

This isn’t the first time Lake Pepin has been threatened. Historian John Anfinson, author of The River We Have Wrought, points out that the city of St. Paul disposed of its garbage directly in the river until the late 1800s. The waste stream included vast quantities of horse manure, manufacturing detritus, and untreated human sewage, all of which flowed to Pepin. In one report, Anfinson says, the Corps of Engineers characterized most of the sandbars between the Twin Cities and Wabasha as consisting of a 50-50 mix of garbage and sawdust.

Anfinson says the environmental nadir for Pepin came in the 1920s and ’30s, with most of the pollution coming from the growing cities of Minneapolis and St. Paul. “It was appalling,” he says. “By the 1920s, there were sewage mats that would cover half the river between St. Paul and Hastings.” In times of low water flow, stretches of the Mississippi boasted a frightful ratio: one gallon of sewage to every 5.8 gallons of water.

Ironically, relief came to the river as a result of a very unnatural alteration of the river: the construction of Lock and Dam 2 at Hastings in 1930. The new structure effectively transformed a large stretch of the Mississippi into a sewage pond. Trash that once flowed unimpeded into Pepin started to back up, creating a repulsive stench along the river corridor. This olfactory outrage sparked calls for action, and, in 1938, the Twin Cities sewage treatment plant, just south of downtown St. Paul, near Pig’s Eye Lake, was completed. It was a key triumph in the modern environmental history of the upper Mississippi—in Anfinson’s view, on par with the passage of the Clean Water Act in the 1970s. The Mississippi was once again transformed. Pepin’s fisheries, which were on the verge of collapse in 1929 due to low oxygen and industrial pollutants, recovered. An environmental apocalypse was forestalled.

Today, the minnesota river is the principle source of the sediment flowing into Lake Pepin, according to the MPCA and a host of researchers. Remember that Foshay Tower analogy? The Minnesota accounts for the first 24 stories of that sediment skyscraper. “The Minnesota River is the big lion,” Senjem says. “Everything else is kind of dwarfed.”


By the time that lion crosses the state from east to west, from Big Stone Lake to Minneapolis, where it merges with the Mississippi at Fort Snelling, it is often the color of the soil. The confluence of the two rivers is telling: The brown waters of the Minnesota run along the west bank, sharply demarcated from the blue waters of the Mississippi, as if stroked with a brush. Further downriver, the waters commingle and the Mississippi, relatively clear for most of its journey through Minnesota, takes on the hue of its tributary. The Mississippi is thus transformed into the Big Muddy, and it delivers its taint straight to Pepin, which, like the trap on a sink drain, collects much of the pollution.

Saving Lake Pepin necessarily involves cleaning up the Minnesota River. But while cleaning up the Minnesota has been a perennial ambition for a generation of state governors, the lofty goal has gone largely unrealized. One reason: It’s a big job. The watershed covers 16,000 square miles, and much of that acreage is under row-crop cultivation—fields of corn and soybeans, engineered to shed water.

“We’ve wiped out all the wetlands on the Minnesota River. Then we ditched, drained, and tiled to beat the band to get the water off the fields,” explains geologist Daniel Engstrom, head of the Science Museum’s St. Croix Watershed Research Station and a leading expert on the sedimentation on Pepin.

As a consequence, when it rains or the snow melts, the water reaches the Minnesota River and its tributaries much more quickly. Because the land holds less water, the water also flows in greater volumes, contributing to ever more erosion in the ravines, bluffs, and streambeds.

Stanching that flow will require taking farmland out of production, according to Engstrom, and that will take money. “We’re not going to get farmers to do things that are not in their economic benefit,” he ventures. “If we want clean water, we are going to have to pay for it.”

As the price of cropland surges upwards of $5,000 an acre, that will be an expensive proposition. Under a state-federal partnership called the Conservation Reserve Enhancement Program, the government has spent $244 million on conservation easements along the Minnesota River between 1997 and 2002. CREP set aside some 100,000 acres of farmland, but in recent years, as those easements expired and commodity prices rose, more farmers have put that fallow land back in use.

Many farmers bristle at the implication they are to blame for Pepin’s woes, and feel vilified by the terms of the debate, says Warren Formo, the executive director of the Minnesota Agricultural Water Resources Coalition, a commodities group.

Formo questions some of the MPCA’s research. He contends the agency may not have adequately analyzed the role of urban runoff, wastewater discharges, and the continued dredging of the river for navigation. Besides, says Formo, “Much of the sediment is naturally occurring and, with today’s technology, there’s not a lot we can do about it.” He suggests there should be more dredging in Pepin. “There may be things we can do that will help with Lake Pepin,” Formo says, “but we don’t know enough yet.”

In a joint letter sent to the MPCA in March, the Minnesota Soybean Growers Association and the Minnesota Corn Growers Association signaled the terms of the coming scrum. The groups formally requested a public hearing on the MPCA’s proposals and, in a comprehensive data-practices request, asked the agency to produce the voluminous documentation used in its decision-making.

The growers’ request could further delay the MPCA’s implementation of new standards, says Trevor Russell, watershed director for the St. Paul–based advocacy group Friends of the Mississippi River.

The MPCA’s proposal, he says, is the product of “an unprecedented public stakeholder engagement process and unparalleled investment in research and study.” And he takes a dim view of the agriculture groups’ “11th hour” request for more information.

“This is one of those circumstances where scientific evidence and common sense match up pretty well,” Russell says.

For Mike McKay, the big worry is whether Pepin can afford the coming tug-of-war and inevitable recriminations. He has a businessman’s yearning for quick action and wants to go after “the low-hanging fruit”—for instance, getting counties to insist that landowners maintain buffer strips along creeks and streams. Such buffers are mandated by existing state law, but, McKay says, those rules are often overlooked in farm country.

“Our message is that there are some commonsense things that we know would work. Start with them. Success breeds success,” McKay says. “We just need to get some of these fixes started.”

Mike Mosedale is a freelance writer, photographer, and river rat. He lives in Minneapolis.