 Its course exhibits many examples of the erosive powers of extremely large glacial Missoula Floods of the late Pleistocene, which scoured the region.In addition, Crab Creek and its region have been transformed by the large-scale irrigation of the Bureau of Reclamation's Columbia Basin Project (CBP), which has raised water table levels, significantly extending the length of Crab Creek and created new lakes and streams.Crab Creek is long and drains a watershed in eastern Washington of .