America's Most Endangered Rivers is a list of threatened rivers in the United States compiled by the nonprofit group American Rivers. First published in 1984, the annual list spotlights ten threatened rivers–rivers that are facing environmental degradation due to existing or proposed development projects. The list is intended to build public awareness and spur action toward addressing specific environmental issues.
Most-listed rivers
A number of rivers have been listed on America's Most Endangered Rivers multiple times, either in whole or in part. This list includes items that have appeared three or more times.
Times listed River First listed Last listed14Snake River 1991 202313Mississippi River 1991 202512Colorado River 1991 2023Missouri River 1994 20219Columbia River 1988 20158Penobscot River 1989 19966American River 1988 1996Big Sunflower River 2002 2024Klamath River 1987 2003Rio Grande 1993 2025San Joaquin River 1997 20265Animas River 1988 2001Chattahoochee River 1996 2016Platte River 1987 2003Rogue River 1993 2026Susquehanna River 1988 20164Alsek River 1990 1993Boundary Waters 2013 2026Coosa River 1999 2022Flint River 2000 2016Hudson River 1996 2019Kansas River 1995 2012Passaic River 1990 2025Potomac River 1997 2026Tatshenshini River 1990 19933Apalachicola River 2000 2016Black River 1986 1988Rivers of Bristol Bay 2006 2018Catawba River 2001 2013Chilkat River 2019 2026Clarks Fork Yellowstone River 1994 1996Coal River 1999 2012Pearl River 2008 2023Gila River 2008 2019Kern River 1986 2022Little Bighorn River 1987 1989Merrimack River 1986 2016Niobrara River 1986 2013Pinto Creek 1996 1998Skykomish River 2005 2017Smith River (Montana) 2015 2018South Fork Salmon River 2018 2020Tallapoosa River 1999 2003White Salmon River 1996 2007
Lists
2026 rivers
On April 14, 2026, American Rivers announced its ten most endangered rivers of 2026.
Rank River State(s) Threats 1 Potomac River MD, VA, DC Data center construction and a major sewage spill 2 San Joaquin River CA Proposed gravel mine 3 Boundary Waters MN Twin Metals mine 4 Lumber River NC, SC PFAS pollution 5 Rogue River OR Mining pollution and potential roadless rule rollback 6 Chilkat River AK Hard rock mine development 7 Nissequogue River NY Reconstruction of a failed dam 8 Dan River NC, VA Pipeline construction 9 Amargosa River CA, NV Mining operations 10 Suwannee River FL, GA Overuse and pollution
2025 rivers On April 15, 2025, American Rivers announced its ten most endangered rivers of 2025.
Rank River State(s) Threats 1 Mississippi River MN, WI, IL, IA, MO, KY, TN, AR, MS, LA Changes to FEMA and other federal agencies impacting flood prevention and response 2 Tijuana River CA Severe chemical, sewage, and trash pollution 3 Rivers of Southern Appalachia NC, SC, TN, GA Flooding and landslides from Hurricane Helene and future storms 4 Passaic River NJ, NY Incomplete chemical pollution cleanup efforts 5 Lower Rio Grande TX Water scarcity and pollution 6 Rappahannock River VA Over-withdrawal due to increased water demand 7 Clearwater River Basin ID Pollution and habitat destruction from proposed logging, mining, and dam-building 8 Susitna River AK Pollution from road construction and petroleum extraction 9 Calcasieu River LA Pollution from chemical plants and oil refineries 10 Gauley River WV Pollution from strip mining in the Cherry River headwaters
2024 rivers On April 16, 2024, American Rivers announced its ten most endangered rivers of 2024.
Rank River State(s) Threats 1 Rivers of New Mexico NM Loss of federal protections 2 Big Sunflower and Yazoo Rivers MS Pumping project 3 Duck River TN Over-withdrawal 4 Santa Cruz River AZ Scarcity, climate change 5 Pee Dee River NC, SC Development, road construction 6 Farmington River CT, MA Dam 7 Trinity River CA Mismanagement 8 Kobuk River AK Road construction, mining 9 Tijuana River CA Pollution 10 Blackwater River WV Highway development
2023 rivers
On April 18, 2023, American Rivers announced its ten most endangered rivers of 2023.
Rank River State(s) Threats 1 Grand Canyon of the Colorado River AZ Climate change, mismanagement 2 Ohio River PA, OH, WV, KY, IN, IL Pollution, climate change 3 Pearl River MS Dredging, dams 4 Snake River ID, OR, WA Dams 5 Clark Fork River MT Pollution 6 Eel River CA Dams 7 Lehigh River PA Development 8 Chilkat and Klehini Rivers AK Mining 9 Rio Gallinas NM Climate change, mismanagement 10 Okefenokee Swamp GA, FL Mining
2022 rivers
On April 19, 2022, American Rivers announced its ten most endangered rivers of 2022.
Rank River State(s) Threats 1 Colorado River CO, UT, AZ, NV, CA, WY, NM Climate change, mismanagement 2 Snake River ID, OR, WA Dams 3 Mobile River AL Pollution 4 Maine's Atlantic salmon rivers ME Dams 5 Coosa River TN, GA, AL Pollution 6 Mississippi River MN, WI, IL, IA, MO, KY, TN, AR, MS, LA Pollution, habitat loss 7 Lower Kern River CA Over-withdrawal 8 San Pedro River AZ Over-withdrawal 9 Los Angeles River CA Development, pollution 10 Tar Creek OK Pollution
2021 rivers
On April 13, 2021, American Rivers announced its ten most endangered rivers of 2021.
Rank River State(s) Threats 1 Snake River ID, OR, WA Dams 2 Lower Missouri River MO, IA, NE, KS Mismanagement, climate change 3 Boundary Waters MN Mining 4 South River GA Pollution 5 Pecos River NM Mining 6 Tar Creek OK Pollution 7 McCloud River CA Dams 8 Ipswich River MA Over-withdrawal 9 Raccoon River IA Pollution 10 Turkey Creek MS Development
2020 rivers
On April 14, 2020, American Rivers announced its ten most endangered rivers of 2020.
Rank River State(s) Threats 1 Upper Mississippi River MN, WI, IL, IA Climate change, mismanagement 2 Lower Missouri River MO, IA, NE, KS Climate change, mismanagement 3 Big Sunflower River MS Habitat loss 4 Puyallup River WA Dams 5 South Fork Salmon River ID Mining 6 Menominee River MI, WI Mining 7 Rapid Creek SD Mining 8 Okefenokee Swamp and St. Marys River GA, FL Mining 9 Ocklawaha River FL Dams 10 Lower Youghiogheny River PA Natural gas
2019 rivers
On April 16, 2019, American Rivers announced its ten most endangered rivers of 2019.
Rank River State(s) Threats 1 Gila River NM Over-withdrawal 2 Hudson River NY Storm-surge barrier 3 Upper Mississippi River IL, IA, MO Levees 4 Green-Duwamish River WA Habitat loss 5 Willamette River OR Dams 6 Chilkat River AK Mining 7 South Fork Salmon River ID Mining 8 Buffalo National River AR Pollution 9 Big Darby Creek OH Development 10 Stikine River AK Mining
2018 rivers
On April 11, 2018, American Rivers announced its ten most endangered rivers of 2018.
Rank River State(s) Threats 1 Big Sunflower River MS Pumping project 2 Rivers of Bristol Bay AK Mining 3 Boundary Waters MN Mining 4 Lower Rio Grande TX Habitat loss 5 South Fork Salmon River ID Mining 6 Mississippi River Gorge MN Dams 7 Smith River MT Mining 8 Colville River AK Development 9 Middle Fork Vermilion River IL Pollution 10 Kinnickinnic River (St. Croix River tributary) WI Dams
2017 rivers
On April 11, 2017, American Rivers announced its ten most endangered rivers of 2017.
Rank River State(s) Threats 1 Lower Colorado River AZ, NV, CA Climate change, over-withdrawal 2 Bear River CA Dams 3 South Fork Skykomish River WA Hydropower 4 Rivers of Mobile Bay AL, GA, MS Mismanagement 5 Rappahannock River VA Fracking 6 Green-Toutle River WA Mining 7 Neuse and Cape Fear Rivers NC Livestock pollution 8 Middle Fork Flathead River MT Oil transport 9 Buffalo National River AR Livestock pollution 10 Menominee River MI, WI Mining
2016 rivers
In April 2016, American Rivers announced its ten most endangered rivers of 2016.
Rank River State(s) Threats 1 Apalachicola-Chattahoochee-Flint River Basin AL, FL, GA Mismanagement 2 San Joaquin River CA Mismanagement 3 Susquehanna River PA Dams 4 Smith River MT Mining 5 Green-Duwamish River WA Dams, pollution 6 Pee Dee River NC Dams 7 Russell Fork River KY, WV Mining 8 Merrimack River MA, NH Pollution 9 St. Lawrence River NY Dams 10 Pascagoula River MS, AL Dams
2015 rivers
On April 7, 2015, American Rivers announced its ten most endangered rivers of 2015.
Rank River State(s) Threats 1 Grand Canyon of the Colorado River AZ Development, mining, groundwater depletion 2 Columbia River WA, OR Dams 3 Holston River TN Pollution 4 Smith River MT Mining 5 Edisto River SC Over-withdrawal 6 Chuitna River AK Mining 7 Rogue and Smith Rivers OR, CA Mining 8 St. Louis River MN Mining 9 Harpeth River TN Pollution, over-withdrawal 10 Pearl River MS, LA Dams
2014 rivers
On April 9, 2014, American Rivers announced its ten most endangered rivers of 2014.
Rank River State(s) Threats 1 San Joaquin River CA Mismanagement 2 Upper Colorado River CO Water diversions 3 Middle Mississippi River MO, IL, KY Mismanagement 4 Gila River NM Water diversions 5 San Francisquito Creek CA Dams 6 South Fork Edisto River SC Over-withdrawal 7 White River (Colorado) CO Petroleum development 8 White River (Washington) WA Dams 9 Haw River NC Pollution 10 Clearwater and Lochsa Rivers ID Industrializaton
2013 rivers
In April 2013, American Rivers announced its ten most endangered rivers of 2013.
Rank River State(s) Threats 1 Colorado River CO, UT, AZ, NV, CA, WY, NM Mismanagement 2 Flint River GA Mismanagement 3 San Saba River TX Mismanagement 4 Little Plover River WI Mismanagement 5 Catawba River NC, SC Coal ash pollution 6 Boundary Waters MN Mining 7 Black Warrior River AL Mining 8 Rough & Ready and Baldface Creeks OR Mining 9 Kootenai River MT, ID Mining 10 Niobrara River NE, SD, WY Sedimentation
2012 rivers
In May 2012, American Rivers announced its ten most endangered rivers of 2012.
Rank River State(s) Threats 1 Potomac River MD, VA, PA, WV, DC Pollution 2 Green River WY, UT, CO Pumping project 3 Chattahoochee River GA Dams 4 Missouri River CO, IA, KS, MN, MO, MT, NE, ND, SD, WY Mismanagement 5 Hoback River WY Natural gas 6 Grand River OH Natural gas 7 South Fork Skykomish River WA Dams 8 Crystal River CO Dams 9 Coal River WV Mining 10 Kansas River KS Dredging
2011 rivers
In May 2011, American Rivers announced its ten most endangered rivers of 2011.
Rank River State(s) Threats 1 Susquehanna River NY, PA, MD Natural gas 2 Rivers of Bristol Bay AK Mining 3 Roanoke River VA, NC Mining 4 Chicago River IL Sewage pollution 5 Yuba River CA Dams 6 Green River (North Fork Toutle River tributary) WA Mining 7 Hoback River WY Natural gas 8 Black Warrior River AL Mining 9 St. Croix River WI, MN Bridge project 10 Ozark National Scenic Riverways MO Overuse, mismanagement
2010 rivers
On June 2, 2010, American Rivers announced its ten most endangered rivers of 2010.
Rank River State(s) Threats 1 Upper Delaware River NY, PA Natural gas 2 Sacramento–San Joaquin River Delta CA Mismanagement 3 Gauley River WV Mining 4 Little River NC Dams 5 Cedar River IA Mismanagement 6 Upper Colorado River CO Water diversions 7 Chetco River OR Mining 8 Teton River ID Teton Dam reconstruction proposal 9 Monongahela River PA, WV Natural gas 10 Coosa River AL Dams
2009 rivers
On April 7, 2009, American Rivers announced its ten most endangered rivers of 2009.
Rank River State(s) Threats 1 Sacramento and San Joaquin Rivers CA Mismanagement 2 Flint River GA Dams 3 Lower Snake River ID, OR, WA Dams 4 Mattawoman Creek MD Development 5 North Fork Flathead River MT Proposed mines 6 Saluda River SC Sewage pollution 7 Laurel Hill Creek PA Over-withdrawal 8 Beaver Creek AK Proposed petroleum development 9 Pascagoula River MS Proposed petroleum storage project 10 Lower St. Croix National Scenic Riverway MN, WI Development
2008 rivers
In May 2008, American Rivers announced its ten most endangered rivers of 2008.