The Chicago River never has run clear.
Before settlers arrived, it was a lethargic prairie river that ran through a swamp the Potawatomi called Checaugou for swamp weed, or wild onion.
Then factories and slaughterhouses turned it into a sewer. At the confluence of the main branch with the north and south branches, Bubbly Creek was named for the methane gas that rose from decomposing carcasses on the river bottom.
In this region, nearly every river is a good paddling river.
For adventure, try northwest Wisconsin's Bois Brule, which flows into Lake Superior over a series of rapids.
For scenery, head for the cliff-lined Upper Iowa, which National Geographic Adventure magazine calls one of Americas Best Adventure 100, along with rafting in the Grand Canyon.
In Duluth, there's water a lot of water beyond the big lake and the Aerial Lift Bridge.
The St. Louis River is the largest U.S. tributary to Lake Superior, and it creates a huge estuary as it approaches the lake.
Fishermen and bird-watchers have frequented it for years, and more are showing up as the water becomes cleaner. Sturgeon have come back, eagles nest, and 70 percent of the birds seen in Minnesota come through on fall and spring migrations.
Along Minnesota's northern border with Canada, more than 200,000 people a year find an increasingly rare commodity absolute wilderness.
The million-acre Boundary Waters Canoe Area Wilderness is barely changed since voyageurs used its chain of lakes and rivers to push deep into the continent's interior.
Today, the foot trails over which they carried canoes and 180-pound packs are used by vacationers, who wind their way from lake to lake in search of the perfect combination of woods, water and solitude.
In Wausau, water is power.
Sawmills were first to use the thundering rapids along the Wisconsin River, which have been working hard ever since.
But these rapids generate more than the electricity that lights a bulb they also draw world-class athletes for thrilling tournaments, such the 2012 world whitewater kayak/canoe championships for juniors and under-23 paddlers, some of them Olympics-bound.
In the northeast corner of Wisconsin, a vast, amoeba-shaped body of water spreads over 37,000 acres of state-owned land.
Rivers run through it, the Turtle and the Flambeau. They were dammed to create a flowage in 1926, and today it's a state scenic waters area, designated for boating, fishing and camping.
Hundreds of islands and secluded bays provide habitat for bald eagles, osprey and loons, who outnumber the paddlers who pull up to rustic campsites.
At Prairie du Sac, the Wisconsin River finally breaks free.
Lined with so many dams and reservoirs it's often called the nation's hardest-working river, the Wisconsin devotes itself to play after it passes the town.
Then it becomes the Lower Wisconsin State Riverway, beloved by canoeists, who like to play on its many sandbars.
In southwest Wisconsin, following the Kickapoo River is a lot like watching a magic act: No matter how closely you pay attention, eventually what you see is going to disappear into thin air.
When it reappears, it will be in a completely different spot, and you'll have no idea how it got there.
"Look, there it is again," said my husband, as we drove Wisconsin 131 through the Kickapoo Valley. "It's meandering like mad."
On Wisconsin's Kinnickinnic River, paddling is a lot like playing pinball except your boat is the ball.
Quickened by springs and creeks as it flows toward the St. Croix, the Kinni is no lazy river.
Whitewater paddlers are, by definition, thrill-seekers.
That's why they seek out the northeast corner of Wisconsin, "the cradle of rivers.'' The big Wisconsin River starts there, as do the Wolf, Peshtigo and Menominee, three of the Upper Midwest's best-known whitewater rivers.
On the Wolf River, Bear Paw Outdoor Adventure Resort has been a whitewater hub since 1994, selling gear to expert wranglers and teaching novices how to handle the rapids that churn over knots of boulders dropped by the last glacier.
On rivers, only salmon like to paddle upstream.
People like to paddle the easy part, then get a shuttle from friends or outfitters. But there's another way to get back to your car by bicycle.
Rail trails in this region often follow rivers, so it's easy to make a loop.
There's no better way to see nature's loveliest landscapes than on a river, the original highway.
The same rivers that carried hunters, explorers and traders now carry us, the sightseers. Paddling along, we see the same things they did: otters, eagles, fish and deer, plus lovely flora and endless sky.
Best of all, you never see the same thing twice.
If you're interested in sea kayaking and ready to jump in, kayaking festivals are a good place to improve skills and meet other kayakers. Programs include classes, seminars, demos, on-water tours and, often, races.
Sign up as early as possible for the best selection of classes and tours. Youths get discounts. Below are some of the best festivals.
July, Door County Sea Kayak Symposium near Ellison Bay, Wis. This big festival, sponsored by Rutabaga in Madison, is based at the Rowleys Bay Resort on the Lake Michigan side of the peninsula. Passes include some meals.
In Minocqua, you have to get in a boat to go on a historic home tour.
In the first part of the 20th century, captains of industry streamed to this village in northeast Wisconsin, called the Island City because it is nearly surrounded by Lake Minocqua.
Their estates are hidden in the trees, but the boathouses were built over water, fanciful structures with gables, balconies, towers and turrets.
The sky was clear, the wind was still and Lake Superior was as placid as a lily pond.
It was a miracle that wouldn't last.
That's why it was torture for the dozen of us to sit through a long kayak safety course on the sandy beach of Bayfield, Wis., forming a ''human knot'' to foster cooperation in case of disaster and listening to trip leader Hovas Schall's horror stories about the big, mercurial lake.
After a long, hard winter, the sight of blooming forsythia can be intoxicating. And a butterfly? That must be just a fleeting dream.
My daughter spotted those things plus a robin soon after we arrived in Missouri for spring break, and they were enough to make her giddy with excitement.
"Oh, I like this place,'' she cried. "I like the way it looks, the warm spring air, the way it smells. And oh, look, some nice spring grass!''
More than any other river in Wisconsin, the Bois Brule has a pedigree.
They call it River of Presidents, but it also attracts senators and millionaires. Named for pines charred by lightning strikes burnt wood in Ojibwe, then French it rises from conifer bogs near Solon Springs and flows toward Lake Superior.
Its cold, spring-fed currents harbor trout, and well-heeled fishermen discovered the river long before loggers moved in.
In Wisconsin's Driftless Area, the 400 Trail and Baraboo River go together like ice cream and cones.
One is good. Both is better.
They follow each other for 22 miles, the trail only a few feet above the river and its sloughs. Snapping turtles think the trail is a beach, depositing their eggs into its crushed limestone, and fishermen walk the trail to get to secret fishing holes.
Early spring is not too soon to start planning a summer on the water.
Outdoors and paddle clubs are happy to show the ropes to new members.
Outdoors stores offer boat demos and free classes on trip planning. Rangers at federal wildlife reserves offer guided trips.
When some men reach a certain age, they get the urge to buy a zippy little sports car. But when women reach a certain age, they covet a sporty little kayak.
I must be at that age, because nearly every woman I know either has bought a kayak or decided she wants one.
And buying one kayak usually just makes you want another one call it kayak envy.
At the top of Lake Superior, there's a dramatic coast lined with rugged cliffs, cobblestone beaches and islands.
It's the home of Parks Canada's new Lake Superior National Marine Conservation Area, created last October to protect the waters between the Sibley Peninsula, east of Thunder Bay, and the Slate Islands, off Terrace Bay.
The many islands are big, much like the Apostles in Wisconsin except closer together. That makes them ideal for kayaking. The Slate archipelago, where caribou live, attracts serious kayakers. But the Rossport Islands are perfect for any paddler.
For a lot of people, canoeing is last year's sport. Kayaking is a step up, like trading in the mini-van for a Miata.
Who wouldn't want a zippy little kayak to pilot all by yourself, without that other person yelling at you from the stern (or bow)?
But a kayak with all the accessories is expensive. And it's hard to decide what kind of boat to buy, because you need a different kind for different bodies of water whitewater, lakes, rivers and inland seas, such as the Great Lakes.