The headwaters of the Mississippi River in Itasca State Park is an international mecca — a destination for more than half a million visitors who come from around the world every year to walk across the tiny stream that grows into America's greatest river.

But after 80 years of so much love, the site has become worn. The banks are eroding from foot traffic and wear from the water's current, the width of the stream has nearly doubled, and it's filling with sand. Now, the Minnesota Department of Natural Resources (DNR) is faced with a delicate task: how to fix the Mississippi headwaters without really changing it.

The DNR plan would redirect the water's flow away from the sides toward the center of the stream by adding a curved arch of boulders on the downstream side of the dam. It would also make the rock wall easier to walk across by adding some flatter stones. Erosion from all those feet would be slowed by inserting some flat stones along the banks, interspersed with native bushes and water plants.

"We want to keep the aesthetics historically accurate, but let the public use it as they've done since the 1930s," said Dave Radford, an archaeologist with the DNR.

The dam hasn't really changed since the 1930s, when the Civilian Conservation Corps built it to mark the spot where the Mississippi "begins to flow on its winding way 2,552 miles to the Gulf of Mexico," as the carved sign there reads.

That was well after the park was created, in 1891, primarily to protect the last of the old growth pine trees that loggers had stripped from the rest of the state. Those giants, which are still there, were famously defended by the 24-year-old park superintendent, Mary Gibbs, who faced down armed loggers, only to lose her job later under pressure from the timber industry.

In fact, the attraction of the headwaters was a bit of an afterthought. Originally, the river emerged from a marshy area on the edge of the lake. The low dam, built below the water's surface by the Conservation Corps, is still there but now covered by the boulders that serve as steppingstones for millions of visitors.

Today, Itasca is the third most-visited park in the state, after Gooseberry Falls on the North Shore of Lake Superior and Fort Snelling south of the Twin Cities. And virtually everyone who comes to the park stops by the headwaters, said Bob Chance, manager of Itasca State Park.

"People are enthralled by it," he said. "They are amazed that it is that small."

Small enough for kids to run back and forth, shallow enough for horseplay and for everyone to boast how they "walked across the Mississippi."

Chance said that when he walks through the parking lot he sees license plates from all over the country, but a surprisingly large number come from the states that border the Mississippi River, all the way down to Louisiana.

Dan Wilson, a member of Friends of Itasca, said he's spent hours watching people walk the path from the Mary Gibbs visitor center to the headwaters.

"It seems very much that the short trek … takes on a certain sacred quality," he said. "The start of something of wonder as the river begins its long meander through the middle of our nation, impacting the lives of millions."

Wilson had guests from Nepal who compared the experience to the reverence Buddhists have for the Ganges River in India. They took some of the water home with them in plastic bottles.

Small but important

Although the headwaters dam project is among the DNR's smallest — coming in at an expected $10,000 to $20,000 and covering just 2,000 square feet — officials said the headwaters' popularity and historic significance make it among the most important. The idea, said Luther Aadland, a river ecologist and the DNR's dam expert, is to pretty much replicate what the CCC did in the 1930s.

"A lot of it they built well," he said. They used an arched formation, which moves water to the center of what was a 30-foot-wide stream at the bottom, which would cut a deeper channel and protect the banks.

But over the years the stream bed splayed out, forcing water to the sides. Today the dam is essentially a straight line, and the stream is about 70 feet wide and shallower than it was. Left in its current condition, water from the lake would cut around the sides and start to undermine the dam below, Aadland said.

The plan he designed calls for adding boulders on the downstream edges, creating an arch that, like a lens bending light, forces the flow toward the middle. Gravel added between the boulders on top will slow the loss of sand that flows through from the lake. And flat stones on top and along the shore will still give visitors better footing and easy access.

The project still needs many levels of approval, from the Minnesota State Historic Preservation Office, from within the DNR, and perhaps from the U.S. Army Corps of Engineers, state officials said. But if all goes according to plan, construction will begin in the fall, using rocks and plants from within the park itself.

And by next spring it will be ready for the next reverent wave of pilgrims.

This story was reported as part of a fellowship with the Institute for Journalism & Natural Resources.

Josephine Marcotty • 612 673 7394