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Clark Fork River flows into new channel in life after Milltown Dam

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MILLTOWN - Finally, the Clark Fork River can relax.

After five years of being dammed, diverted, diked and dirtied, the big river got to flush away the final ghost of Milltown Dam on Thursday.

At 10:42 a.m., Envirocon excavator operator Dave Kramer started ripping out the last diversion dike, a mile above the confluence of the Clark Fork and Blackfoot rivers where the dam used to stand.

At 11:01 a.m., water started rippling into the new serpentine channel. Cobbles in the new riverbed disappeared under the muddy flow, while the adjacent bypass channel started showing a bathtub ring as its current drained away.

"This will never be quite the same after today," U.S. Environmental Protection Agency Milltown project manager Diana Hammer said as the river shifted course. "Of course, how many times have we said that here, every year for the past five years? It's getting hard to explain. There are so many things that aren't here anymore."

Riverbank resident Chuck Erickson no longer has a reservoir out his windows, nor a slough channel for ice skating. He also doesn't have drinking water contaminated with heavy metals leaching out of the massive sludge mound trapped behind Milltown Dam.

"That reservoir was our playground," Erickson joked. "Not everybody gets to swim in an arsenic bath."

Erickson recalled the winter of 1996, when an ice jam pushed the river between his house and barn and pushed the community to think about "when" the dam might fail instead of "if" it might.

"That's when I really got on board," said Erickson, who's now president of the Bonner Community Council. The council was one of several volunteer groups that outlined what they wanted to see beyond a hazardous waste removal project.

What they wanted was a river corridor that was healthy, natural and publicly accessible. Now, with the removal of 3 million tons of toxic sediment, the planting of nearly that many trees and bushes and the transfer of hundreds of acres of floodplain to the state of Montana for a future park, all those goals are bearing fruit.

At the same moment the Clark Fork entered its new channel, NorthWestern Energy Co. lands and permitting manager Pat Asay was signing over title to 415 acres of river bottom to the state as part of the settlement of damages from the century of mining pollution in the reservoir.

Combined with recent acquisitions from The Nature Conservancy and Five Valleys Land Trust, most of the shorelines and hillsides around the old dam site are now in public hands.

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Even nature seemed to lend a hand in Thursday's historic events.

"We lucked out with the weather," Envirocon project manager Kris Cook said as he watched the excavator tear out the diversion dike. "Two weeks ago, we were worried about the cold. We were pulling chunks of ice four feet thick off the end of the bridge."

Although the Thursday morning mercury hovered around 14 degrees, the Clark Fork was mostly ice-free after a week of warmth. Instead, Cook's biggest problem was a leaky tire on one of the two dump trucks hauling dike material away. To prevent a blow-out, the truck could only take half-loads. And that meant opening the new channel took about 30 minutes instead of 20.

The new channel had standing water in most of its length due to rising groundwater and runoff from the surrounding hills. But about an hour after Cook saw the water pass through the dike, watchers a mile away at the western end of the channel saw ripples trouble the surface.

Over 15 minutes, threads of muddy current mingled through the still water. The Clark Fork steadily spread across its new bed, poking holes in the bank separating it from the mouth of the bypass channel.

Over the next five or six months, Envirocon and Helena Sand and Gravel workers will finish erasing traces of their work in the floodplain. They will restore the bypass channel to a more natural appearance, although it will continue to function as a high-water side channel in future floods.

On Thursday, they scrambled to reroute a bridge ramp from the Envirocon field office that used to drop into the new channel, but now must make a 90-degree turn to stay out of the water. The bridge itself will soon be removed as the bypass channel drains out.

"The river's about 30 feet below where it used to be," said Western Water hydrologist Gary Decker.

The former reservoir used to crest just below an old railroad grade at the base of University Mountain, easily seen from Interstate 90 where it crosses the Blackfoot River near Bonner.

"When we were looking at the conceptual plan eight years ago, there were 15 pretty ambitious things on the list," Decker said. "I figured we'd be lucky to get half of them done. Now I think we've got all but about three, and we'll have two more before summer. It will be hard to top this."

Reporter Rob Chaney can be reached at 523-5382 or at


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