- 1 Has Missoula ever flooded?
- 2 Where did the Missoula Flood start?
- 3 Why did Glacial Lake Missoula drain?
- 4 What is the largest flood in history?
- 5 How many times did Lake Missoula flood?
- 6 How deep is the Clark Fork River?
- 7 How many days did it take Glacial Lake Missoula to drain?
- 8 What happened to Glacial Lake Missoula at the end of the last ice age?
- 9 How many Ice Age floods passed through the Columbia Gorge?
- 10 How does a lake in Missoula MT relate to the Megafloods?
- 11 What was the biggest flood in Washington state?
- 12 What geological evidence did the Bonneville flood leave behind?
Has Missoula ever flooded?
The Missoula floods (also known as the Spokane floods or the Bretz floods or Bretz’s floods) were cataclysmic glacial lake outburst floods that swept periodically across eastern Washington and down the Columbia River Gorge at the end of the last ice age. These floods have been researched since the 1920s.
Where did the Missoula Flood start?
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.
Why did Glacial Lake Missoula drain?
Glacial Lake Missoula formed as the Cordilleran Ice Sheet dammed the Clark Fork River just as it entered Idaho. The rising water behind the glacial dam weakened it until water burst through in a catastrophic flood that raced across Idaho, Oregon, and Washington toward the Pacific Ocean.
What is the largest flood in history?
The largest known meteorological flood—one caused by rainfall, as in the current Mississippi River flood—happened in 1953, when the Amazon River overflowed.
How many times did Lake Missoula flood?
It was the largest ice-dammed lake known to have occurred. The periodic rupturing of the ice dam resulted in the Missoula Floods – cataclysmic floods that swept across eastern Washington and down the Columbia River Gorge approximately 40 times during a 2,000 year period.
How deep is the Clark Fork River?
While the Interstate roughly parallels the river, the Clark Fork is generally located deep down in a canyon, usually a hundred feet or more below the level of the road.
How many days did it take Glacial Lake Missoula to drain?
The repeated filling and collapse of the ice dam would drain an inland sea the size of Lake Erie and Lake Ontario in two days. At its greatest extent, Glacial Lake Missoula stretched eastward a distance of some 200 miles. When the lake rose high enough, it burst through the ice dam.
What happened to Glacial Lake Missoula at the end of the last ice age?
At the end of the last Ice Age, about 18,000 to 15,000 years ago, an ice dam in northern Idaho created Glacial Lake Missoula in Montana. The ice dam burst and released flood waters across Washington and down the Columbia River back flooding into Oregon before eventually reaching the Pacific Ocean.
How many Ice Age floods passed through the Columbia Gorge?
At least two floods seem to have passed down the Columbia valley after the last of the Missoula floods, including a large flood about ~14 ka likely from cataclysmic demise of the thinning Okanogan ice lobe dam impounding glacial Lake Columbia.
How does a lake in Missoula MT relate to the Megafloods?
Water in the Clark Fork ponded up behind an enormous ice dam from a lobe of the Cordilleran Ice Sheet, and reached a maximum depth of 600 meters as Glacial Lake Missoula.
What was the biggest flood in Washington state?
The National Oceanic and Atmospheric Administration (NOAA) says 1942 holds the record, measured at the southwest waterfront, followed closely by the monster flood of 1936. Old news accounts agree. The 1942 flood was brought on by 5.4 inches of rain that fell in Washington over 77 hours in the third week of October.
What geological evidence did the Bonneville flood leave behind?
The evidence indicates that it existed at least 600,000 years ago. As the climate became cooler and wetter, Lake Bonneville expanded in size, gradually spreading over a surface area of about 20,000 square miles and overlapping into Nevada and Idaho. Because Lake Bonneville was in a basin, it lacked natural outlets.