Musselshell River - Geography

Geography

The terrain varies from the mountainous island ranges where it originates to prairie. It is fed largely by snowmelt and has its highest flow rates in the spring and early summer. The Musselshell River Basin, including tributaries, drains 108,268 acres (438.1 km2). The South Fork has lots of brush, gravel bars, and clear water. The North Fork has willow trees and undercut banks. The Musselshell is about 60 feet (20 m) wide at its confluence of the two forks. Three reservoirs built in the 1930s help control the river's flow: Bair Reservoir on the North Fork, Martinsdale Reservoir near the confluence, and Deadman's Basin on the main river between Shawmut and Ryegate. The river becomes wider in the 50 miles (80 km) before Roundup. Honeysuckle, wild rose, willow, and cottonwood are common in this section. The river is about 100 feet (30 m) wide in its last 90 miles (140 km), with increased choppiness and flow rate. The relatively more arid climate in this section results in less vegetation, more livestock grazing, and poorer soil. Additional tributaries of the Musselshell include: Middle Fork, Bozeman Fork, Dry Fork, American Creek Fork, Big Elk Creek, Careless Creek, Cottonwood Creek, Flat Willow Creek, Hopley Creek, Spring Creek, Swimming Woman Creek, and Willow Creek.