Hydropower Reservoir Levels

Hydropower reservoirs are a significant source of low‑cost electricity in many regions. When reservoir levels are high, hydropower plants can produce more electricity and displace costly fossil generation. Low water levels, often due to droughts or seasonal factors, reduce hydro output and force grids to rely on more expensive fuels, pushing rates higher.

For additional context on electricity supply and price dynamics, see our Installed Reserve Margin indicator and the U.S. Bureau of Reclamation’s hydropower reservoir data.