What is a “kolk” pond and how does it relate to the Missoula Floods?
A kolk pond is best described as an underground tornado that occurs in deep flows of fast-moving water. About 15,000 years ago a vast lake known as Glacial Lake Missoula periodically burst through an ice dam releasing a catastrophic wall of water containing icebergs, boulders, and debris flooding the Tualatin and Willamette Valleys. They tore huge potholes in the scablands and flung debris out of the floodwaters. Wilsonville’s Coffee Lake Wetlands sits in a “kolk” or depression in the bedrock scoured out by the prehistoric Glacial Lake Missoula Floods.
