Moses Coulee the southern portion of the plateau. These streams had combined into a canyon that drained to the Columbia near the current mouth of Moses Coulee. These side drainages are still visible today along the coulee walls as truncated streambeds, interspersed with gable-like highlands. The Okanogan lobe of the Cordilleran Glacier moved down the Okanogan River valley, covering 500 mi² of the Waterville Plateau and blocked the ancient route of the Columbia River, backing up water to create Glacial Lake Columbia and Lake Spokane. Initially water discharged from Lake Columbia by running up through the head of Grand Coulee and down
Birch Coulee Battlefield Birch Coulee Battlefield Birch Coulee Battlefield in Renville County, Minnesota, United States, was the site of the Battle of Birch Coulee, the costliest military engagement for U.S. forces during the Dakota War of 1862. It is now a historic site with self-guided trails and markers interpreting the battle from both sides. Birch Coulee was nominated to the National Register of Historic Places for having state-level significance in military history, and was listed in 1973. Birch Coulee Battlefield lies on what, in 1862, was open prairie stretching on to the north and west, with woods to the south. Defining the east