Lake Powell is a massive reservoir on the Colorado River spanning Utah and Arizona, created by the flooding of Glen Canyon via the Glen Canyon Dam and named after explorer John Wesley Powell. Serving as a vital water storage facility for the Upper Basin states (Colorado, Utah, Wyoming, and New Mexico) under the Colorado River Compact, it holds up to 24.3 million acre-feet of water, making it the second-largest reservoir in the U.S. Construction of the dam began in 1956 (initiated by President Eisenhower) and was completed in 1963, with the lake taking 16 years to fill completely by 1980. A popular vacation destination attracting about two million visitors annually, the reservoir faces significant environmental challenges, including an average annual loss of storage capacity due to sediment buildup from the Colorado and San Juan rivers. Environmentalists have advocated for draining the lake to restore Glen Canyon's natural state, while the water level fluctuates dramatically with seasonal snowmelt, reaching its all-time high in 1983.