Like an itinerant riverboat captain, Chad Pregracke spends his days traveling the upper Mississippi River, anchoring at towns large and small with a contemporary purpose -- single-handedly leading a cleanup of the river he grew up on.

On this summer evening he is visiting Lansing, Iowa, and as he motors a skiff past forested bluffs and coulees, he spots bald eagles in the trees and old Indian caves in the cliffs.

On shore he identifies every plant and tree around him: silver maples, cottonwoods, an occasional oak. Watch out for the poison ivy and stinging nettle, he says. Isn't it "cool" how the irritating plants' remedy, jewelweed, grows right beside them? he remarks.

In between all this he is retrieving car tires, 55-gallon metal drums, refrigerators, chunks of polystyrene foam -- any piece of refuse one can dump into a river.

Freckle-faced with a big, toothy smile and blue eyes, the 5-6 Pregracke and his youthful enthusiasm about the Mississippi conjure up a creation of Mark Twain. And his Huck Finn-like journeys don't hurt the image.

After seven years of traversing the river full time from Kentucky to Minnesota, Pregracke, 29, enjoys a growing reputation as the latest intrepid and colorful figure to ply the nation's most storied waterway.

He grew up just feet from the shoreline in Hampton, Ill., near East Moline. By 15 he was working summers as a commercial mussel diver in the river, where your hands are your eyes in the murky water. By 22, unable to further stomach the trash ashore and afloat, he used his 20-foot johnboat to collect the junk, piling it temporarily in his parents' yard.

Now he commands a crew of six, all but one also in their twenties, aboard a 272-foot barge with a towboat whimsically painted with fish and named the River Clean Up. He operates under Living Lands & Waters, a $500,000-a-year nonprofit group he started in 1998 and maintains with fundraising.

The sight of his leviathan floating along much of the 908-mile Upper Mississippi often leaves landlubbers astonished at the tons of debris he's collected and will continue to gather until Christmastime, when he'll deliver the hulking piles to recyclers and scrap yards.

While evoking the romantic wanderings of Twain's literary characters, Pregracke hardly speaks the language of Huck. Instead, the former longhaired skateboarder favors a vocabulary of "gnarly," "rad," "stoked" and, of course, "dude."

Though his mother, KeeKee, 59, a retired college administrator, likens him to the Twain protagonist, her son cringes at the comparison, saying the character is a slacker who could never have accomplished what Pregracke has. Twain wrote that Huck, son of the town drunkard, was "idle and lawless and vulgar and bad."

"Huck Finn? I don't know about Huck Finn. I don't think he was that hard of a worker," Pregracke said.

"But he was adventurous. That's cool. I like living on the river, but I'd better: I'm out here nine months a year, and the other months I'm sleeping in cars to save money while I'm out fundraising because hotels are too expensive."

What has set Pregracke apart from the scores of other do-gooders cleaning up the Mississippi is his gumption -- as well as his fleet: a house barge and three flat barges tied together that were donated by businesses; a towboat; an end loader and crane on deck; five aluminum-plated work boats from 24 feet to 30 feet in length; and three pickups and a box van, all with boat trailers.

"It's just really refreshing to see a kid -- he started young and he's still young -- who said, 'Hey, here's a problem and here's a solution: There's trash in the river and let's pull it out,'" said James Falvey, acting executive director of Mississippi River Basin Alliance, a coalition of about 150 grass-roots groups protecting the vast watershed between the Rocky and Appalachian Mountains.

"Does pulling trash out solve all our problems? Absolutely not. But what he does is he creates a lot of awareness, and that's good," Falvey said. "I just can't say enough good things about him and his whole organization."

As word of his accomplishments and armada has spread, Pregracke has provided boats or barges or both for community cleanups on the Ohio, Missouri and Kaw rivers, and farther east on the Potomac and Anacostia rivers. In October he'll make a special trip 186 miles up the Illinois River, to Starved Rock State Park near Utica, Ill., and nearby Plum Island and the town of Seneca, Ill., for a one-month cleanup of trash in and along the river.

"Part of the story isn't about garbage or the river. It's about the simple fact of seeing something you don't like and doing something about it," Pregracke said. "Not that I'm a super-environmentalist. No, that's not it. That's not what I want to be known as. I'm just a hardworking American."

At each river town, Pregracke and crew hold community cleanups and workshops featuring speakers from the U.S. Fish and Wildlife Service or the Audubon Society. Or local commercial fishermen and barge captains speak about the beauty and industry of the Mississippi or other waterways.

About 20 participants at one such all-day workshop in Prairie du Chien, Wis., couldn't get over the 60 tons of trash accumulated so far on his barge deck, including about 20 refrigerators, 70 plastic or metal drums, 100 tires, 17 channel buoys and a fenced pen of plastic foam and other rubbish piled 10 feet high.

That is a relatively small load, however. By December, Pregracke estimates he'll have collected 200 tons of recyclable material and trash, enough to more than cover a football field to a depth of two to three feet. In the past seven years, he and Living Lands & Waters, based in East Moline, have collected 900 tons of junk from the Mississippi and other rivers, much of it now recycled.

"If I hadn't known him, I would say to myself, 'What the heck is this?' " said Ann Wallin, 55, a grade-school teacher in Seneca, Wis., who attended a workshop on the barge. "It's funny to be instructed by such young 'uns."

"I remember when I saw him on TV. I said, 'Jeez, it's just a kid out there, he's not going to have much luck in this business,' " teacher Ken Hollenberger, 62, of Eastman, Wis., said of Pregracke. "Who in the heck is going to give you money to clean up the river? No one cares, and he was the first, and it's always hard when you're the first. It's just super."

Midwestern companies such as agribusiness giant Cargill and brewer Anheuser-Busch have donated $50,000 and more to Pregracke's enterprise. His salary is $40,000 a year, though if he still was a commercial fisherman or shell diver he could be making as much as $60,000, he said.

And it all began after Pregracke, then a community college student, became frustrated with Illinois officials because they didn't take seriously his environmental complaints, dismissing him as a naive upstart. When state officials didn't respond to his demands that they clean up the river, he began doing it himself.

"His reputation is he'll do it without us if he must," said David Robinson, 51, site manager of a 3M plant in Prairie du Chien, whose corporate foundation has given $20,000 this year to Pregracke and crew. "They remind me of how I hoped I had been 30 years ago."

Pregracke has spent the last seven years plying the Mississippi and other rivers in a cleanup effort that has netted 900 tons of junk, much of it now recycled.Lisa Hoffman, part of Pregracke's six-person crew, transfers trash from one work boat to another near Lansing, Iowa.Pregracke and Hoffman clear a block of plastic foam. Above, Woodson Spring soaps up for a bath in the river.