Facility

Glen Canyon Dam / Lake Powell (Bureau of Reclamation)

Glen Canyon Dam (Page, AZ; completed 1966; 710-foot concrete arch dam; 1,320 MW nameplate capacity; operated by Bureau of Reclamation) creates Lake Powell — the second-largest US reservoir by capacity (24.32 MAF) and the primary Upper Basin storage buffer. Lake Powell sits just upstream of Lee's Ferry — the official gauge point for the Colorado River Compact that divides Upper Basin from Lower Basin allocations. Reclamation must release sufficient water past Lee's Ferry to meet the Lower Basin's 7.5 MAF/yr Compact entitlement. In extreme drought, if Lake Powell cannot sustain minimum power pool (3,525 ft elevation; ~6.1 MAF), Glen Canyon Dam turbines cannot generate power. In 2022, Lake Powell reached its historic low: 3,522 feet — 3 feet BELOW minimum power pool — temporarily impairing hydroelectric generation. Reclamation conducted emergency upstream reservoir releases (from Flaming Gorge and other Upper Basin reservoirs) to prevent Glen Canyon Dam shutdown, the first time such emergency action was taken. Source: https://www.usbr.gov/uc/water/crsp/cs/gcd.html