The
Green River, located in the western
United States, is the chief tributary of the
Colorado River. The
watershed of the river, known as the
Green River Basin, covers parts of
Wyoming,
Utah, and
Colorado. The Green River is long, beginning in the
Wind River Mountains of Wyoming and flowing through Wyoming and Utah for most of its course, except for into western Colorado. Much of the route is through the
Colorado Plateau and through some of the most spectacular
canyons in the
United States. It is only slightly smaller than the Colorado when the two rivers merge, but typically carries a larger load of
silt. The average yearly mean flow of the river at
Green River, Utah is per second.