For the first time in centuries, the United States is removing more dams than it builds. What once symbolized progress, power generation, and expansion is now being dismantled in favor of healthier rivers, safer communities, and restored ecosystems. More than 2,200 dams have already been removed, most within the past 25 years, marking one of the biggest environmental course corrections in modern U.S. history.
The country is full of dams – over 550,000 of them. Many date back more than a century, built to power mills, float timber, irrigate land, and generate electricity. Hydropower was once tied to national progress, particularly during the mid-1900s dam-building boom that gave rise to structures like Hoover Dam and Grand Coulee. These feats of engineering reshaped rivers, flooded valleys, and supported growing cities and wartime industries.
But ecological and economic realities have shifted. Most U.S. dams no longer provide energy, water, or flood protection. Only about 3 percent produce hydropower today. Thousands serve no modern purpose, yet they block fish migration, degrade water quality, and transform rivers into stagnant reservoirs that heat up and fuel invasive species. For migratory fish such as salmon, dams have been catastrophic. In North America, nearly 40 percent of freshwater fish are now imperiled, and dozens have gone extinct since 1900.
Communities that once relied on dams have also begun questioning them. Indigenous nations, whose fishing rights and cultural sites were buried under reservoirs, have pushed for removals as an act of environmental and cultural restoration. On the Klamath River, the removal of multiple dams has been described by tribal leaders as reversing cultural erasure rather than simply fixing an ecosystem.
Safety has become an equally urgent issue. The average U.S. dam is nearly 60 years old, and thousands are considered high-hazard, meaning their failure would threaten human life. Maintenance costs have ballooned, with rehabilitation estimates exceeding 190 billion dollars according to national engineering assessments. For many owners, demolition is cheaper than repair.
Meanwhile, climate change has exposed weaknesses in aging structures. Storms are stronger and more frequent, meaning reservoirs can overflow and worsen flooding rather than prevent it. In drought-stricken regions, huge reservoirs behind dams remain too low to produce power or supply cities.
Dam removal is proving effective almost immediately. Rivers reopen. Sediment trapped for decades flushes downstream, rebuilding beaches and wetlands. Fish return to upstream habitats without ladders or bypass systems. Communities reconnect with waterways that had been silent for generations.
The movement is accelerating. Environmental organizations and state agencies are forming partnerships to target aging, redundant dams. American Rivers has set a goal to remove 30,000 dams by 2050, unlocking hundreds of thousands of miles of river habitat.
While not every dam will come down, a national shift is underway. Instead of dominating rivers, the U.S. is beginning to restore them, revealing what was lost and demonstrating how returning nature to its original path can benefit people, wildlife, and future generations.
