No, I meant that we shouldn’t be storing water at the Glen Canyon Dam, since two large shallow lakes have more surface area. And on this scale, evaporation actu

No, I meant that we shouldn’t be storing water at the Glen Canyon Dam, since two large shallow lakes have more surface area. And on this scale, evaporation actually matters—consider the shade balls used in California reservoirs. But for some reason, upstream folk think that if the let the water go they will never see it again. This is not the way legal allotments work. But it’s the same reason people prefer dams to underground storage, because seeing things feels reassuring, despite it being less efficient.