For nearly two centuries, man has had his way with the Shenango River.

The river was a major transportation route during the days of the Erie Extension Canal and for most of the last century its waters cooled the machines and diluted the waste of industries that lined its banks from Jamestown to Farrell and points south.

The evidence of that use is apparent along the stretch of the river from Sharpsville to Farrell, from the remnants of canal towpaths and chunks of concrete laying along the banks to rusty, little used railroad trestles and the oily sheen the river takes on south of Sharon.

The surprise, one learned after taking a Shenango River Watchers-led canoe trip down that stretch last week, is that those sights are few and far between. For most of the trip, you see the same thing you'd see on a July afternoon on the "clean" stretches of the river north of Shenango River Lake: Lush trees, river grass, small rocky beaches, some wildlife, a few fishermen and -- yes -- discarded tires and household junk too big to throw out and too hard to burn.

About 30 people, guided by River Watchers founders Jennifer and Rick Barborak, put in at a verdant spot below the dam and took out a few miles downstream, pulling their canoes out on a concrete slip deep in the industrial wasteland that once housed Sharon Steel. In between they wound their way through Sharpsville, Sharon and Farrell, leaving Pennsylvania for a few moments at the point where the river meanders into Ohio.

Leaving the park below the dam in Sharpsville, the group passed under the first of several bridges along the route. First there are active and derelict railroad trestles -- rusty Erector-set pieces that back in the day carried a constant stream of trains whose sparks, old timers say, would sometimes set the chemically-enhanced river on fire. Then there are the ugly cement and rebar slabs PennDOT calls bridges and the truly frightening State Street Bridge, its undercarriage flaking paint and rust in equal parts.

From Sharpsville to Sharon the river is mostly lined with trees and scrubby bushes, a fishing path here and there and a few signs of man's hand -- a railroad grade, some industrial ruins and a half-submerged lawn tractor. The river is calm here, with a few riffles and a "tight spot" that didn't live up to the hype. For a while it runs alongside the former River Road Landfill but you'd never even know that the hill sloping up from the tree-lined river bank was a dump that has been closed for a decade.

The group pulled their canoes out of the river under the bridge at Clark Street in Sharon. To pass further takes boaters close to the "line of doom" above Consumers Pennsylvania Water Co., Shenango Valley Division's low level dam. Boaters are not allowed within 200 feet of the dam above and 100 feet below. That used to just be a good idea, but in the post-911 world of tightened security around public water supplies it's a necessity you don't want to play around with. (Though some say there is a portage path around the dam on the Sharon Tube side of the river.)

The water company's dam pools water for the plant to draw off for treatment -- about 10 million gallons a day, or 10 percent of the water in the river, according to Consumers' Ken Baumann. After treatment, the now safe-to-drink water is pumped to just about every community in the valley.

The river never changes, but south of the water company the land around it does. The overhanging trees are replaced by overgrown bushes and stunted trees that give way to retaining walls. The Winner, Sky Bank and Protected Life loom overhead. Downtown, the river starts to look a little rough, not capsize rough, but shabby.

Mocking nature lovers, a great blue heron took flight over the group just as the canoes entered Sharon and the river started to take on a full-spectrum shine courtesy of motor oil and years of industrial abuse. The heron flew ahead of them for the rest of the trip, past Bicentennial Park and a canoe launch the River Watchers and the city of Sharon are building off Budd Street.

After the river passes under U.S. Route 62, the tree line thins out enough to see the relics left by industries of the past and work still being done at factories along the river. A little further down the river, a sign on a trestle warns of an upcoming low level dam -- and it's a good thing, too. The three-foot drop-off is is nearly invisible to the untrained eye. Bouncing over it would be an unpleasant surprise to an inatttentive boater. Built for Sharon Steel, the dam now serves Duferco Farrell Corp. and other companies operating on the mammoth site in Farrell.

Perhaps fittingly for a group dedicated to cleaning up the Shenango, the River Watchers ended their trip there, in sight of acres of land that has been designated as contaminated by pollutants that are inexorably seeping into the river.

For more information about Shenango River Watchers, contact the group at (724) 342-5453.or online at: www.shenangoriverwatchers.org