Human-driven activities – including the creation of data centers, mining and pollution – are threatening the nation’s water supply, leaving 80% of U.S. rivers without “adequate protection” and half with unsafe levels of pollution, according to the conservation organization American Rivers in its 2026 annual report of the country’s most endangered rivers released Tuesday.
Millions of Americans rely on rivers for drinking water, economic stability, food supply irrigation and outdoor recreation. Every year since 1984, American Rivers has published a list of rivers – nominated by individuals and organizations across the country – that are deeply significant to people and nature, under serious threat and might endanger surrounding communities, and the subject of upcoming government decisions with the potential to alleviate the threat.
1. Potomac River: Maryland, D.C., Virginia