Grand Coulee displacing local Native Americans. Grand Coulee The Grand Coulee is an ancient river bed in the U.S. state of Washington. This National Natural Landmark stretches for about 60 miles (100 km) southwest from Grand Coulee Dam to Soap Lake, being bisected by Dry Falls into the Upper and Lower Grand Coulee. The Grand Coulee is part of the Columbia River Plateau. This area has underlying granite bedrock, formed deep in the Earth's crust 40 to 60 million years ago. The land periodically uplifted and subsided over millions of years giving rise to some small mountains and, eventually, an inland sea.
Moses Coulee thrasher, sage sparrow, poorwill, mountain bluebird, loggerhead shrike, canyon wren, white-throated swift, golden eagle), plants (sagebrush buttercup, shooting star, sulphur lupine, serviceberry, mock orange, slender cryptantha, Tiehm's rush, big sagebrush, bluebunch wheatgrass and sego lily) and animals (mule deer, least chipmunk, bats, and marmot). Moses Coulee Moses Coulee is a canyon in the Waterville plateau region of Douglas County, Washington. Moses Coulee is the second-largest and westernmost canyon of the Channeled Scablands, located about to the west of the larger Grand Coulee. This water channel is now dry, but during glacial periods, large outburst floods with discharges greater than carved