Western Hydropower at Risk

The Hoover Dam began generating electricity in 1936 and was a reliable source of power for the U.S. Southwest. However, fast-forward 90 years and the Dam’s ability to produce electricity anywhere close to its full capacity is at risk. Lake Mead, which is the reservoir feeding the Dam from the Colorado River, now sits at record low water level of 1,039 feet. As a result, electricity generation is down by 33%. If the reservoir falls much lower, the majority of the installed electric turbines will be forced offline due to insufficient water pressure.

The Hoover Dam delivers clean power to customers in Arizona, California and Nevada. When fewer Dam electrons flow to these states, they must acquire electricity from other power producers, such as thermal power plants burning fossil fuels. This impacts utility rates and the carbon intensity of electricity. Notably, California and Nevada have statutory requirements to reduce greenhouse gas emissions, including from the electric power sector, while Arizona has an executive order to reduce energy consumption.

Lake Mead isn’t the only Western reservoir in distress. Lake Powell, which feeds the Glen Canyon Dam, is also at a record low water level. This has greatly reduced the Dam’s electricity output and impacted the seven states who rely on it for power. In 2024, hydropower accounted for six percent of all U.S. electricity generation, with most of that occurring in the West. For more information, contact NPGA’s Senior Director of State Advocacy & Affairs, Jacob Peterson.