Crow Creek is a 153-mile-long (246 km) waterway of southeastern Wyoming and northern Colorado. Crow Creek is formed by the merger of the South Fork of Crow Creek with the Middle fork of Crow Creek, with the quick addition of the North Fork of Crow Creek about 1.5 miles (2.4 km) downstream. All the major tributaries of Crow Creek begin in the Laramie Range and flow eastward. The headwaters of the North Fork are dammed to form North Crow reservoir, which supplies the city of Cheyenne. The middle fork is also dammed forming Granite and Crystal reservoirs, also supplying water for Cheyenne. The South Fork is the only unobstructed section and flows most of the year but not all the way to Cheyenne. Other tributaries of Crow Creek below the reservoirs are Sand Creek, Spring Creek and Brush Creek,