Actually its' the Glen Canyon portion of the the Colorado River upstream of Lee's Ferry between GCNP and Glen Canyon Dam that creates Lake Powell. (Marble Canyon Trading Post at Lee's Ferry) is a destination. The river as a managed tailwater of cold water releases creates a zone of unique trout fishery possibilities for North America with the once endangered Humpback chub.
Remember the endemic ecosystem minnow that live here are the
trout FOOD! With water demand exceeding demand use Lake Mead for water storage. Lake Powell for flow management we can do both as water flows in one end and out the other we're in charge. Lake Mead & Powell have shad populations. In between everything wants to eat these chubs. Farm these minners, we're the deciders.
These fishes already know how to doit if we create the sandbars.