Why do hydroelectric dams have limited lifetimes?

It is safe to dewater the reservoir and remove the structure because water flow from the catchment area will fill it with mud, sand, and other materials. An accident could wash away vast tracts of land and kill thousands of people in the lower area.

Hydroelectric dams have limited lifetimes primarily due to sedimentation, erosion, and reservoir siltation. Over time, sediment carried by rivers accumulates in the reservoir, reducing its storage capacity and affecting the dam's efficiency. Additionally, erosion and corrosion of dam components occur due to water flow and environmental factors. Material fatigue, aging infrastructure, and changing safety standards also contribute to the limited lifespan of hydroelectric dams. Regular maintenance can mitigate some issues, but eventual decommissioning or significant upgrades become necessary to address these challenges effectively.