America’s Most Endangered Rivers® Report: 1986 – 1995

Below is a list of the nation’s Most Endangered Rivers from 1986-1995, including the states in which they flow and the primary threat that caused them to be listed.

1995 ~ 1994 ~ 1993 ~ 1992 ~ 1991 ~ 1990 ~ 1989 ~ 1988 ~ 1987 ~ 1986

Most Endangered Rivers 1995

  • Clarks Fork of the Yellowstone (MT, WY)–gold mine
  • Los Angeles (CA)–flood control; urban neglect
  • Columbia and Snake (WA, OR, ID)–dams, irrigation
  • Animas (CO)–water development project
  • Missouri (Midwest, Great Plains)–navigation, ag runoff
  • Kansas (K)–ag runoff, sand dredging
  • Mississippi (Midwest)–ag runoff, flood control
  • Cheat (WV)–acid mine drainage, proposed dam
  • Penobscot (ME)–dams
  • Thorne (AK)–logging

Threatened

  • Elwha (WA)–damsLittle Bighorn (WY)–hydro
  • Rogue/Illinois (OR)–dams, logging
  • Skokomish (WA)–dams, logging
  • Gila and San Pedro Rivers (AZ, NM, Mexico)–overallocation and ag pollution
  • New (CA, Mexico)–ag runoff
  • Rio Grande (Southwest; Mexico)–ag grazing
  • Russian (CA)–dams, development, ag waste
  • San Jacinto (TX)–toxic chemical pollution
  • Virgin (AZ, NV, UT)–overallocation
  • Minnesota (MN)–ag runoff
  • Platte (NE)–dams, irrigation
  • West Pearl (LA)–dredging for navigation
  • Wolf (WI)–copper and zinc mine
  • Anacostia (D.C., MD)–development, sewer overflows, highway
  • Chattahoochee (GA, AL, FL)–sewage, development
  • Everglades (FL)–diversions, ag pollution
  • Fish Creek (NY)–logging, development
  • Moisie and Sainte Marguerite Rivers (Quebec)–hydro
  • Neuse (NC)–ag runoff

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Most Endangered Rivers 1994

  • Clarks Fork of Yellowstone (WY, MT)–mine
  • Anacostia (D.C., MD)–urban run-off
  • Clavey (CA)–dams
  • Columbia, Snake Rivers (WA, OR, ID)–dams, logging
  • Mississippi–flood control, run-offMissouri–dams and channelization
  • Penobscot (ME)–proposed dam
  • Rio Grande, Rio Bravo (CO, NM, TX, Mexico)–agricultural pollution, mine waste, toxics
  • Thorne (AK)–logging
  • Virgin (UT, AZ, NV)–diversion for ag, development

Threatened

  • Blackfoot (MT)–gold mine
  • Fraser (BC, Canada)–hydro
  • Fortymile (AK)–mining
  • Rogue/Illinois (OR)–dams, logging
  • Skokomish (WA)–dams
  • Tongue (MT, WY)–railroad, coal mining
  • Animas (CO)–diversion for ag
  • Los Angeles (CA)–flood control project
  • San Pedro (AZ)–groundwater pumping
  • Santa Margarita (CA)–development, dams
  • Snowmass (CO)–snow making
  • Chippewa/Flambeau Rivers (WI)–dams
  • Eleven Point (Missouri)–lead mining
  • Platte (NE)–dams
  • Trinity (TX)–dams
  • Chattahoochee (GA, AL)–untreated sewage, development
  • Clinch/Powell Rivers (VA, TN)–ag runoff
  • Everglades (FL)–dikes, canals; ag pollution (sugar production)
  • Moisie and Saint Marguerite Rivers (Quebec)–hydro
  • Saugus (MA)–proposed building of tidal floodgates

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Most Endangered Rivers 1993

  • Rio Grande and Rio Conchos (CO, NM, TX, Mexico)–sewage and indust pollution
  • Columbia and Snake Rivers, including Yakima tributary (Northwest; Canada)–dams
  • Everglades (FL)–diversion, ag and animal waste
  • Anacostia (D.C., MD)–sewage, development, ag sedimentation, dumping
  • Virgin (UT, AZ, NV)–dams
  • Rogue and Illinois (OR)–logging
  • Penobscot (ME)–hydro
  • Clavey (CA)–hydro
  • Alsek and Tatshenshini (AK and BC)–copper mine
  • Platte (NE)–dam

Threatened

  • Animas (CO)–diversion
  • Beaverkill (lower) and Willowemoc Rivers (NY)–development, land use
  • Blackfoot (MT)–ag runoff
  • Eleven Point (MO)–drilling for lead
  • Great Whale (Quebec)–proposed hydro
  • Little Bighorn (WY)–proposed hydro
  • Los Angeles (CA)–flood control
  • Moose Creek (AK)–riverbed mining
  • Skokomish (WA)–hydro
  • St. Mary’s (VA)–acid rain, fossil fuel burning power plant
  • Susquehanna (PA)–ag runoff
  • Tennessee (KY)–indust dumping, hazardous waste
  • Thorne (AK)–logging
  • White (AR)–ag and animal waste
  • Yuba (CA)–proposed dam

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Most Endangered Rivers 1992

  • Columbia and Snake Rivers (OR, WA, ID)–dams
  • Alsek and Tatshenshini (AK)–open pit copper mine 
  • Great Whale (Quebec)–hydro project
  • Everglades (FL)–flood control project
  • American (CA)–proposed dam
  • Colorado (AZ)–Glen Canyon dam
  • Mississippi (Midwest)–hydro, barge spills, agriculture and pesticides, industrial discharge
  • Penobscot (ME)–proposed dam
  • Beaverkill and Willowemoc (NY)–logging and development
  • Blackfoot (MT)–logging, cattle grazing, poor agricultural practices, mining

Threatened

  • Animas (CO)–irrigation project
  • Clavey (CA)–dams, diversions
  • Elwha (WA)–dams
  • Gunnison (CO)–proposed hydro
  • Illinois (OR)–water diversion for domestic use and irrigation
  • Klamath (OR)–hydro diversion
  • New (NC)–development
  • Ohio (IN, IL, KY, OH)–dams
  • Ouachita (AR, LA)–channel widening, navigation project
  • Passaic (NJ)
  • Rio Conchos (TX)–logging; hazardous waste landfills
  • Savannah (GA)–hydro; nuclear waste; urban run-off; agricultural pollution
  • Susquehanna (PA)–hydro project
  • Verde (AZ)–residential development; groundwater withdrawals
  • Virgin (AZ, NV, UT)–overallocation; dams

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Most Endangered Rivers 1991

  • Colorado (AZ)–Glen Canyon dam
  • Alsek and Tatshenshini (AK)–open pit copper mine
  • American (CA)–flood control project
  • Penobscot (ME)–proposed hydro
  • Susquehanna (PA)–proposed hydro
  • Upper Mississippi (Upper Midwest)–oil spills, other hazardous cargo
  • Columbia and Snake Rivers (Northwest)–current dam operations
  • Gunnison (CO)–hydro and diversion project
  • Passaic (NJ)–flood control project
  • New (NC)–land development

Threatened

  • Animas (CO)–proposed irrigation
  • Arkansas (CO)–water projects would flood area
  • Cahaba (AL)–Coalbed methane; development, strip mining, clearcutting, indust & sewage
  • Chattahoochee (GA)–allocation problems, poor water quality
  • Clavey (CA)–proposed dam
  • Fortymile (AK)–gold mining
  • Fremont (UT)–proposed hydro
  • Hanalei (HI)–proposed diversion, flood control, dredging
  • Klamath (OR)–hydro, diversion
  • Lamprey (NH)–proposed hydro
  • Little Bighorn (WY)–proposed hydro
  • Sespe (CA)–proposed water supply dams
  • Spring (AR)–land development
  • Suwanee (FL)–phosphate mining, land development
  • Verde (AZ)–groundwater depletion

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Most Endangered Rivers 1990

  • Klamath (OR)–proposed hydro
  • South Platte (CO)–proposed dam
  • Penobscot (ME)–proposed dam
  • American (CA)–proposed dam
  • Bruneau and Jarbidge (ID)–Air Force missile range
  • Alsek and Tatshenshini (AK)–proposed mine
  • Passaic (NJ)–proposed tunnel to control floods (Corps)
  • Cahaba (AL)–proposed methane gas wells
  • Jemez (NM)–proposed pumice mine
  • James (MO)–proposed dam

Threatened

  • Animas (CO)–irrigation project
  • Chuck (AK)–logging
  • Fortymile (AK)–gold mining
  • Illinois Bayou (AR)–proposed dam
  • James (VA)–proposed hydro
  • Lower Kern (CA)–proposed dam
  • Little Bighorn (WY)–hydro
  • NF Mokelumne (CA)–dam
  • New (NC)–development
  • NF Payette–hydro project
  • Platte (NE)–dam relicensing
  • Sespe (CA)–proposed dams
  • Smith (CA)–clearcutting old growth
  • Suwannee (FL)–phosphate mining and land development
  • Yampa (CO)–proposed dam for irrigation

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Most Endangered Rivers 1989

  • Platte (CO, NE)–proposed dam
  • Klamath (OR)–proposed dam
  • American (CA)–proposed dam
  • Penobscot (ME)–proposed dam
  • Payette (ID)–proposed dams
  • James (VA)–proposed hydro project
  • Little Bighorn (WY)–hydro
  • Illinois Bayou (AR)–proposed dam
  • New (NC)–development of adjacent lands
  • Animas (CO)–irrigation project

Threatened

  • Greenbrier (WV)–controlled flood by Corps
  • Smith (CA)–logging
  • Yampa (CO)–water projects
  • Lower Kern (CA)–hydro projects
  • Oswegatchie (NY)–hydro project
  • Alleghany (PA)–coal burning power plant
  • Niobrara (NE)–proposed dam
  • Mokelumne, North Fork (CA)–dam
  • Clavey (CA)–hydro
  • Big (RI)–reservoir

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Most Endangered Rivers 1988

  • South Platte (CO)–proposed dam 
  • Klamath (OR, CA)–proposed dam
  • Little Bighorn (WY)–proposed hydro project
  • Greenbrier (WV)–proposed flood control dam
  • Platte (NE)–dams
  • Columbia (WA)–proposed dredging in Hanford Reach
  • Susquehanna (PA)–proposed dam
  • American (CA)–proposed dam
  • Animas (CO)–proposed irrigation project
  • Black (NY)–proposed hydro projects

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Most Endangered Rivers 1987

Press release only. No published report. No order of designation.

**All rivers facing proposed dams**

  • Kings  (CA)
  • Merced (CA)
  • Merrimack (NH)
  • Illinois Bayou (AR)
  • Verde (AZ)
  • Klamath (OR)
  • Greenbrier (WV)
  • Platte (CO, NE, WY)
  • Little Big Horn (WY)
  • Black (NY)

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Most Endangered Rivers 1986

Press release only. No published report. No order of designation

  • Kings (CA) proposed hydro project
  • Merced (CA) proposed hydro project
  • Kern (CA) possible dam proposal
  • Maurice (NJ) proposed toxic waste incinerator site
  • Menantico (NJ) proposed toxic waste incinerator site
  • Manumuskin (NJ) proposed toxic waste incinerator site
  • Niobrara (NE) major dam proposals
  • Black (NY) major hydro proposal
  • Rio Chama (NM) plans to raise the pool level of a downstream dam
  • Merrimack (NH) new hydro dam development at Sewalls Falls

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