A new scientific assessment has created a detailed map showing which rivers and streams across the contiguous United States are most resilient and where conservation efforts could make the biggest difference. The four-year study was published in PLOS One.
Mapping River Health
Researchers evaluated river systems using factors including water quality, floodplain condition, water availability and how connected waterways remain for aquatic species. The assessment also considered existing data on freshwater biodiversity.
Why River Connectivity Matters
More than 150,000 dams have fragmented U.S. waterways, affecting the movement of fish and other aquatic species. The new map identifies areas where removing barriers or addressing other problems could help restore river ecosystems.
Some Rivers Are Resilient
More than half of the mapped stream distances were classified as resilient, while other waterways were considered restorable because issues such as agricultural runoff or dams were limiting their health. Rivers along parts of the Pacific Coast, northern Rockies and Southeast showed stronger resilience.
Protection Gap Remains
The study found that only about 6 percent of rivers are both healthy and meaningfully protected. Another 13 percent are in good condition but lack strong safeguards, highlighting the need to protect healthy waterways before their condition declines.
