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Group seeks to designate Glacial Lake Missoula flood route – The Ice Age Floods Institute will hold its annual meeting in Missoula on Sept. 17 and 18.

This story is huge. That’s why Pete Pettersen loves it so much. "It’s just so humongous," Pettersen said.

The lake itself was 200 miles long and, in some places, 2,000 feet deep.

By SHERRY DEVLIN of the Missoulian

http://missoulian.com/articles/2004/08/26/outdoors/od01.txt

Called Glacial Lake Missoula, it was formed by an ice dam that blocked the mouth of the Clark Fork River, backing up water across much of western Montana.

In Missoula, the lake was nearly 1,000 feet deep. Mounts Sentinel and Jumbo were islands. The North Hills were underwater features. Downtown was a long, long way from dry ground.

But the really humongous part of the story came the day maybe 14,000 years ago when the ice dam broke, unleashing a flood of better-than-Biblical proportions.

Near the breach, the floodwaters equaled 10 times the flow of all the rivers in the world today. "Unimaginable really," said Pettersen, who knew nothing of the story until he was invited to a meeting of the Ice Age Floods Institute a few years back.

Now he is the group’s treasurer and an armchair expert on the story.

The flood plowed across the Idaho Panhandle into eastern Washington and eventually into Oregon, where it scoured the Columbia River Gorge en route to the Pacific Ocean.

Moving at speeds reaching 65 mph, boulders the size of houses were deposited as far away as Eugene, Ore. Bedrock carried off the side of Mount Jumbo has been found in the Columbia River Gorge, 1,000 feet above the present-day water level.

The lake left shorelines etched into the mountains above Missoula; the flood left ripple marks on hillsides all across western Montana, and created the Palouse hills and scablands of eastern Washington.

Most of Portland, Ore., is a sand and debris bar deposited as the floodwaters slowed and spread across the Portland Basin. Residents of Lake Oswego still curse at the boulders strewn across (and beneath) their posh lawns.

Glacial Lake Missoula drained in less than two days, forever altering the topography of 16,000 square miles of the Pacific Northwest.

The Ice Age floods of Glacial Lake Missoula are significant in the world’s geologic history, Pettersen said. Relatively few such floods occurred elsewhere.

And no others occurred again and again, as did the Missoula floods over a period of nearly 2,500 years, said Dale Middleton, president of the Ice Age Floods Institute – a group of self-named "floodsnuts" committed to spreading the news.

That’s why the Institute wants Congress to designate the Ice Age Floods National Geologic Trail, a 600-mile-long motor route highlighting the floods’ impact on the topography of Montana, Idaho, Washington and Oregon.

After years of lobbying, the group succeeded this summer in convincing Doc Hastings, a Republican congressman from Washington state, to introduce an Ice Age Floods bill.

Just before Congress recessed for the summer, Hastings and a dozen co-sponsors introduced H.R. 4944, a bill designating the Ice Age Floods National Geologic Trail.

Middleton believes it’ll win approval during the next session of Congress, which begins in January. But he cautions that the bill doesn’t actually "do" a lot.

"About as far as it goes is in indicating that there should be a management and interpretation plan developed over three years," he said. "That’s when we would start to see definite details about the route and any interpretive facilities."

Being at the start of the story, Missoula would almost certainly be home to an interpretive center of some sort, but there would be others along the way.

In fact, Hastings’ support came only after he was convinced that the trail’s designation would be an economic boost for the Tri-Cities of Richland, Kennewick and Pasco, Wash., which he represents.

Hastings was also insistent that the trail have no impact on private property rights. Any development associated with the route would occur on public lands – or on private land where the landowner was willing.

"Primarily, we’re just talking about a driving route," Middleton said. "We’re talking about a wide spot in the road and a sign."

"All the old ideas still work: interpretive signs and markers, little hiking trails maybe, markers that reassure motorists they’re still on the route," he said. "In its format, it would be similar to the Lewis and Clark Trail."

The National Park Service would be responsible for writing the management and interpretive plan for what proponents call "a park without borders."

The intent, Pettersen said, is to develop "consistent interpretation – so you hear the same story whether you’re in Missoula or Wenatchee or The Dalles."

"That’s significant," he said. "The evidence of the flood is different from place to place, but the story is the same."

In a preliminary study, the National Park Service envisioned towns near "key flood features" as gateways to a series of hiking and horse trails, canoeing and kayaking routes, and occasional interpretive centers.

Money, Middleton conceded, will be hard to come by. The floods bill authorizes the spending of up to $500,000 for each of three years, but does not actually appropriate the money.

He also cautions against communities looking at the floodways map and assuming they are – or are not – part of the motor route.

"There are communities that get carried away thinking that all sorts of money will start falling from the sky," he said. "That’s not going to happen."

The trail and its development, he said, will be years and years in the making.

In the meantime, the Ice Age Floods Institute will continue educating the public – and politicians – about the story.

Their next opportunity comes in mid-September when the group holds its annual meeting in Missoula, including an all-day tour of nearby Glacial Lake Missoula topography.

"Interest is growing all the time," Middleton said. "We did a Moses Coulee field trip earlier this year and filled three chartered buses. We could end up having to leave people on the curb in Missoula."

September’s get-together also will include a presentation by University of Montana geologist Marc Hendrix on new research into the relationship between modern-day Flathead Lake and Glacial Lake Missoula.

"There’s still a lot we don’t know," Middleton said. "And there’s actually quite a bit of research going on."

Geologists recently found "new" ripple marks between Alberton and Superior, further evidence of the great lake.

"And everyone wants to know how and why the dam failed," Middleton said. "There are various speculations, none of which have been satisfactorily accounted for. So there’ll be research continuing for years.

"We know there was a lake. We know it was huge. We know the dam failed, and that it was sudden.

"But we want to know more."

Time and again, it’s the size of the lake and its many floods that capture the imagination of converts, Middleton said.

"It just goes on and on," he said. "Although it’s not well-studied, there is evidence that some of the material washed away by the floods made it 1,200 miles out into the Pacific Ocean."

"It’s the real estate that grabs people’s attention," he said. "There are things on the landscape that simply seem out of proportion – things that are too big to ignore."

Reporter Sherry Devlin can be reached at 523-5268 or at [email protected]

If you’re interested

The Ice Age Floods Institute will hold its annual meeting in Missoula on Sept. 17 and 18.

The business meeting begins at 7 p.m. on Friday, Sept. 17, in the St. Patrick Hospital Conference Center, 500 W. Broadway.

A scientific presentation by University of Montana geologist Marc Hendrix follows at 8 p.m. and is open to the public. Hendrix will discuss new findings about the relationship between Flathead Lake and Glacial Lake Missoula.

On Saturday, Sept. 18, the group will sponsor a Glacial Lake Missoula field trip. Again open to all comers (for a fee), the trip runs from 8 a.m. to 6 p.m., and will be led by geologist Norm Smyers of the Lolo and Flathead national forests.

Tour-goers will see geologic evidence of the ancient lake, which was nearly 1,000 feet deep at Missoula and held more than 500 cubic miles of water.

Deadline to register and pay for the field trip is Sept. 9. Cost is $30 for institute members and K-12 teachers, $40 for non-members.

To register for the trip or to join the Ice Age Floods Institute, contact field trip registrar Pete Pettersen, Glacial Lake Missoula Chapter, P.O. Box 3244, Missoula, MT 59806. Or call Pettersen at 728-2330 or e-mail him at [email protected]. Checks should be payable to Ice Age Floods Institute.

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