Rivers That Flow Into Colorado

Colorado is a headwater state—many major rivers originate in its mountains and flow out to neighboring states. However, several rivers flow into Colorado from surrounding states:

• North Platte River – Enters from Wyoming (North Park).
• Laramie River – Tributary of North Platte; enters from Wyoming.
• Yampa River – Minor headwaters in Wyoming; mostly in CO.
• Green River – Brief segment enters NW Colorado from Utah (Dinosaur National Monument).
• San Juan River – Headwaters in Colorado; but tributaries (Animas, La Plata) flow in from New Mexico.
• Republican River – Forks (Arikaree, North Fork) enter from Nebraska/Kansas border area.
• Cimarron River – Headwaters in NM; enters SE Colorado briefly.

Most of Colorado's major rivers (Colorado, Arkansas, Rio Grande, South Platte, Gunnison, Dolores) originate in Colorado and flow out. The state is a net exporter of water.