ICE AGE FLOODS NATIONAL GEOLOGIC TRAIL PASSES CONGRESS
03-25-09. The Trail bill has passed Congress! The Omnibus Public Land Management Act of 2009, a bundle of 164 bills, including the Ice Age Floods National Geologic Trail bill, was passed by the House today after passing the Senate earlier this year. In the House, of the 17 Representatives from the four Northwest states, only Hastings (WA), McMorris Rodgers (WA) and Rehberg (MT) voted "nay", apparently opposing the omnibus but not the Trail bill component. On this vote, a 2/3 majority was not required, but there it is. In the Senate, the preceding vote (3/19) was 77-20, with all 8 of the region's Senators voting in favor. On March 30, President Barack Obama signed the bill into law.

Appropriation of money to staff the trail and create the management plan is the next task. IAFI has submitted electronic budget request materials to the primary sponsors, Senator Cantwell and Congressman Hastings. The job isn't over yet, but this is a really important milestone. Thank you to all who have helped in this long journey. Your many hours (in many cases many years) of writing letters and articles, making phone calls, talking with the public and public leaders, organizing and leading field trips and generally being cheerleaders for the Trail have done the trick.

The public lands bill will also include new protections to the 1,200-mile Pacific Northwest Scenic Trail and launch a program to study and monitor ocean acidification, a potentially devastating greenhouse gas-related development caused by the 22 million tons of carbon dioxide absorbed by the oceans daily. The legislation pulls together 150 separate public lands, parks and water bills in one package. It designates 2 million additional acres as wilderness areas in nine states--though not Washington--authorizes water projects on tribal lands, and designates new wild and scenic rivers.

The National Park Service would oversee the geologic trail, which would cost an estimated $8 million to $12 million to create.

"Our region's ice age flood legacy is etched all over the Pacific Northwest, and this trail will serve as a valuable learning tool to educate Americans on our unique geological history as well as a boost for local tourism," Sen. Maria Cantwell, D-Wash., said in a statement. Cantwell originally had introduced stand-alone bills for the ice age flood trail and the Pacific Northwest Scenic Trail. The lands bill designates the 1,200-mile Pacific Northwest Scenic Trail as a National Scenic Trail, a designation that should provide additional protection and additional funding for maintenance. With scientists increasingly concerned, the public lands bill also requires a comprehensive national research and monitoring program of ocean acidification. Carbon dioxide is changing the chemistry of the oceans, threatening the food chain, from tiny marine animals to salmon.

WHAT ARE THE ICE AGE FLOODS?  When geologists first saw the vast Columbia Basin in eastern Washington State, they recognized that glaciers and flowing water had played a large part in shaping the extraordinary landscape, with its canyons (coulees), buttes, dry cataracts, boulder fields, and gravel bars. It was taken for granted that what they saw was the cumulative effect of familiar processes, operating on a familiar scale.

However, a closer examination of the features in the Basin led one geologist, J Harlen Bretz, to propose that it could only have been a sudden cataclysmic flood, on a scale never before considered possible, that could account for the phenomenal size and distinctive characteristics of the landforms. This radical idea was not well received by fellow geologists, and a long-running scientific dispute followed. Ultimately his extensive field work, plus additional research by others, conclusively established that many extraordinarily huge and powerful Ice Age floods had shaped the region. Two National Natural Landmarks, Wallula Gap and the Drumheller Channels, are the direct result of the floods.

These floods are a remarkable part of our natural heritage. They have profoundly affected the geography and life in the region, but have remained largely unknown to the general public. The legacy of the floods includes not only stark scabland and dramatic dry coulees and cataracts, but also exceptionally fertile, productive farmland, and significant wetlands and aquifers.

Among geologists, the most recent Ice Age Floods in the Pacific Northwest have been called the Missoula Floods, the Spokane Flood(s), Bretz Floods, and Ice Age Floods. By whatever name, their striking effects are undeniable, and available for all of us to see and explore.

HOW WAS THE GEOLOGIC PUZZLE SOLVED?  It was in 1923 that J. Harlen Bretz published the first in a series of scientific papers in which he proposed that the severely eroded Channeled Scabland, Dry Falls, and other immense geologic features had been formed by a huge, powerful flood that had swept through the Columbia Basin during the Ice Age.

Despite his peers' doubt and opposition, he resolutely maintained that direct examination of the geologic evidence could lead only to that conclusion. But Bretz was unable to identify the source or cause of such catastrophic flooding.

Earlier, in 1910, another geologist, Joseph T. Pardee, had described evidence of a great ice dammed lake, Glacial Lake Missoula, that had formed during the Ice Age in northwestern Montana. However, Bretz didn't see the connection between the glacial lake in Montana and the features he described in Eastern Washington. Then, in 1940, Pardee reported on his discovery of giant ripple marks, 50 feet high and 200-500 feet apart, that had formed on the floor of Glacial Lake Missoula. These huge, current-related features, along with other newly-found landforms, dramatically confirmed that the lake had suddenly emptied to the west, unleashing the tremendously powerful erosive forces that shaped many of the landforms found in the Columbia Basin.

More research followed, and new perspectives became available from aerial photography. Among geologists, the concept of a catastrophic flood came to be accepted by the late 1950s.

In the following years the account was refined, as evidence of more than one flood was discovered. It is now established that there were large numbers of Ice Age floods that swept across the Northwest, and some of them were among the largest and most powerful floods that have ever occurred on Earth.

HOW DID THESE FLOODS HAPPEN?  During the most recent episode of major ice-sheet expansion, between about 18,000 and 13,000 years ago, a lobe of the Cordilleran ice sheet advanced into the Idaho Panhandle to the area that is now occupied by Lake Pend Oreille, thus blocking the Clark Fork River drainage and causing Glacial Lake Missoula to form. At its largest, the lake was deeper than 2,000 feet deep at the dam and held over 500 cubic miles of water–as much as Lake Erie and Lake Ontario combined. The ice dam, however, was subject to repeated failure.

The actual failure of the ice dam is inferred from observations of modern glacial floods. Research on glacial floods is relatively new and the physical processes are not yet fully understood, but one scenario is that, when the height and pressure of the lake’s water against the ice dam reached a critical stage, the dam would develop significant subglacial leaks, eventually leading to a sudden and complete collapse.

When the dam broke, a towering mass of water and ice was released and swept across parts of Idaho, Washington, and Oregon on its way to the ocean. The peak rate of flow was ten times the combined flow of all the rivers of the world. The huge lake may have emptied in as little as two or three days. Over a period of years the glacier would advance, once again blocking the river, and the dam and the lake would form again. This process was repeated scores of times, until the ice sheet ceased its advance and receded to the north at the end of the Ice Age. It is assumed that the same processes would have occurred earlier during other glacial advances throughout the Ice Age, although most of the evidence for the earlier events may have been removed by the flooding that occurred during the last glacial advance.

PHENOMENA RELATED TO ICE AGE FLOODS?  Recent research has found evidence that comparable floods occurred much earlier in the Ice Age in the Columbia Basin, as much as 1 to 2 million years ago. It has been determined that huge Ice Age glacial-outburst floods occurred in other parts of the world, as well. Even in our own times, similar but much smaller floods have occurred.

Scientific study of the Ice Age Floods is contributing to the understanding of cyclical climate change and of very large and destructive contemporary floods on Earth. The Ice Age Floods have also been considered as an analog to understand geologic processes on Mars, where landforms strikingly similar to those in Eastern Washington exist.

Could huge floods on this scale happen again? Although global warming may now be a serious concern, it is likely that long-term climate cycles will cause large ice sheets to return at some time in the distant future, and cataclysmic outburst floods will probably recur in this region.

CLARK FORK RIVER. At the end of the last ice age, North America’s last continental ice sheet, the Cordilleran, extended its long "fingers" down several natural trenches reaching into the Pacific Northwest. One of these fingers dammed the Clark Fork River where it crosses today’s Idaho-Montana border creating a mammoth lake. At its peak, the lake, which filled the river valley and many of its tributaries, had an estimated maximum depth of 2,100 feet-168 feet deeper than Crater Lake, the deepest lake in the United States today. It contained 500-600 cubic miles of water-half the amount of water in Lake Michigan and covered an area of 3,000 square miles—twice the size of Rhode Island.

LAKE MISSOULA. Such a colossal amount of water behind and below the ice dam forced it to eventually float and then burst into many gargantuan pieces. The water gushed from the lake at speeds of 50-60 miles per hour. The average rate of flow was at least 9.5 cubic miles per hour, 10 times the combined flow of all the rivers in the world, and may have reached 18 cubic miles per hour. At this rate, Lake Missoula would have drained in merely two days!

COLUMBIA RIVER AND LAKE ROOSEVELT. The torrent of water raced down the Idaho panhandle, surged into the Spokane River Valley and inundated another glacial lake, Lake Columbia. Lake Columbia had formed when another ice lobe had blocked the Columbia River where Grand Coulee Dam sits today. Lake Roosevelt, Washington’s largest lake, is a much smaller version of Lake Columbia which was at least 500 feet deeper than Lake Roosevelt. The massive amounts of water that entered Lake Columbia spilled over the southern walls of the canyon containing the lake and burst forth onto the expansive basalt lava field that covered eastern Washington. New channels connected neighboring valleys as water sliced through the basalt that covered eastern Washington. When viewed on satellite imagery, this pattern of channels dividing and re-crossing looks like a braided river—only this braided river covers three-fourths of eastern Washington.

The Columbia River Gorge is a 50-million-year-old geologic wonder. The Columbia River is one of the major North American rivers draining into the Pacific Ocean. Originating in Northern Idaho and Southeastern British Columbia, it travels some 1200 miles to the ocean, draining much of the Pacific Northwest.

For over 9000 years, people gathered along the banks of the river to fish and trade with each other. Missionaries and explorers for the Hudson Bay Company and the Northwest Trading Company mapped the area and developed relationships with the local Indian tribes.

Lake Roosevelt was created in 1941, by damming the Columbia River. Named after President Franklin D. Roosevelt, the lake is now the largest recreation feature in the Lake Roosevelt National Recreation Area.

DRY FALLS.  The largest channel gashed into the fragile layers of basalt was the Grand Coulee, having carried the greatest amount of water. The Grand Coulee begins just south of the town of Grand Coulee and runs to Soap Lake. Today, it is 50 miles long and its walls stand one to six miles apart and rise 900 feet. At center stage was the world’s largest waterfall, Dry Falls, so named because today no water tumbles over its rim. The falls divide the Grand Coulee into upper and lower halves. Dry Falls now stands 417 feet above the lower channel floor and is 3.5 miles wide. During the climax of the floods, the furious waters raging over the falls were at least 300 feet deep. The lower Grand Coulee was formed as the immense cutting power of the waters racing at speeds of up to 65 miles per hour dissected the basalt plateau: and the falls, which originally were 21 miles to the south, retreated upstream. This same phenomenon is occurring today at Niagara Falls as the base of the falls is undercut.

QUINCY BASIN.  The water rushed into the Quincy Basin and with no other obstacles in its way, spread out over the large open expanse. The mighty waters had snatched huge boulders of basalt and granite from the bedrock along its entire course and then scattered them across the basin as the waters slowed. Fields are now cloaked with thousands of boulders, some the size of a small house.

Other features within the region stand as a legacy to the enormous amounts of water that shaped the area. More than 100 evenly spaced sets of ridges line the Channeled Scablands. In one, the ridges are up to 35 feet high, their crests are 350 feet apart, and the ridges stretch 2 miles long. These types of landforms, ripple marks, are easily identified on a smaller scale on river beds and beaches. These huge ripple marks of the Channeled Scablands are like giant footprints verifying the tremendous amount and direction of the flood waters through the area.

Astonishingly, between 40 and 89 short-lived floods occurred as the ice dams reformed and were repeatedly breached on an average of every 55 years. Usually great canyons, like the Grand Canyon, are formed over eons. The immense Channeled Scablands, with all its unique and interesting features, may have been formed cumulatively in just a matter of months. The massive remnants found on the landscape are evidence of the titanic power of the immense floods which formed this land of giants.

Kid's Cosmos - Fieldtrip to Mars

For links to other floods-related information and resources on the Web, click here.

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