Drumheller Channels National Natural Landmark
Drumheller Channels National Natural Landmark showcases the Drumheller Channels, which are the most significant example in the Columbia Plateau of basalt butte-and-basin Channeled Scablands. This National Natural Landmark is an extensively eroded landscape, located in south central Washington state characterized by hundreds of isolated, steep-sided hills (buttes) surrounded by a braided network of numerous channels, all but one of which are currently dry. It is a classic example of the tremendous erosive powers of extremely large floods such as those that reformed the Columbia Plateau volcanic terrain during the late Pleistocene glacial Missoula Floods.
Drumheller Channels
Ice Age Floods Institute tour of the Drumheller Channels – note the two people in the foreground and the group in the background that provide perspective in the large-scale erosion here.
The Channeled Scablands are a relatively barren and soil-free region of interconnected relict and dry flood channels, coulees and cataracts eroded into Palouse loess and the typically flat-lying basalt flows that remain after cataclysmic floods within the southeastern part of Washington state. The Channeled Scablands were scoured by more than 40 cataclysmic floods during the Last Glacial Maximum and innumerable older cataclysmic floods over the last two million years. These floods were periodically unleashed whenever a large glacial lake broke through its ice dam and swept across eastern Washington and down the Columbia River Plateau during the Pleistocene epoch. The last of the cataclysmic floods occurred between 18,200 and 14,000 years ago.
Drumheller Channels
View downstream of Park Lake Side Canyon, one of the channels which fed floodwaters to Grand Coulee