Would the river running season in Grand Canyon be shortened without regulation by Glen Canyon Dam?
It needn’t be. Before Glen Canyon Dam was built, river runners successfully ran trips throughout the year. In fact, some of the lowest flows on record, which presented significant problems for river runners, occurred after the dam was built as the reservoir was filling. In the early 1970s the dam shut the river down to around 1,000 cubic feet per second (cfs), and during the late 1980s the dam quite often reduced flows to 3,000 cfs. During 1983, releases approached 100,000 cfs. Yet throughout both of these extremes, commercial rafting continued. We don’t need a dam to run a river; people run free flowing rivers all over the world. Cataract Canyon is largely unregulated, and yes, it gets exciting when spring run-off is high. But it is still run commercially. How would a free flowing Colorado River affect river running in Grand Canyon? For one thing, it would be more real.
