The Colorado-Green Confluence: Two Rivers, One Story

From the Confluence Overlook at the southern end of Canyonlands' Island in the Sky district, you can see both rivers at once. The Green comes in from the north, carrying snowmelt from Wyoming's Wind River Range. The Colorado arrives from the east, draining the Rockies from its headwaters in Rocky Mountain National Park. At the point where they meet, a thousand feet below the mesa rim, the canyon walls rise nearly vertically from the water and the river bends southwest toward the Grand Canyon.

John Wesley Powell passed through this confluence in July eighteen sixty-nine, roughly the midpoint of his expedition. He had already lost one of his four boats and much of his food by then. The canyon below the confluence, which he named Cataract Canyon, was the most violent whitewater of the entire journey.

The rivers that meet here are the most over-allocated waterway system in North America. The Colorado River Compact of nineteen twenty-two divided their flow between seven states based on streamflow measurements that turned out to be from an unusually wet decade. A separate nineteen forty-four treaty later allocated a share to Mexico. In drought years, the amount of water the compact promises to deliver does not exist in the river. The political and legal fights over that shortage are ongoing and intensifying as the climate dries. Lake Powell, the reservoir that backs up behind Glen Canyon Dam just downstream, has dropped to levels that have threatened its ability to generate power.

The Diné (Navajo) and Ute peoples whose ancestral territories surround this river system have water rights claims that predate the compact and remain only partially recognized. The rivers are carrying multiple arguments at once, and the water level is dropping.