- Advocacy group American Rivers compiles a yearly list of America’s most endangered rivers.
- This year’s most endangered river is the Colorado River. It’s the river’s second year topping the list.
- Others include rivers in Pennsylvania, New Mexico and Florida.
Climate change and development projects have put many of America’s rivers at risk, but some face greater danger than others, according to a new ranking.
American Rivers, an advocacy group based in Washington D.C. that works with communities to reduce river pollution and create policies that promote clean water and reduce flood risks, compiles a yearly list of the country’s most endangered rivers.
The organization named the Colorado River the most at-risk in the U.S. The federal government in 2021 declared its first water shortage on the essential Western waterway, which has been the subject of interstate litigation and hundreds of millions in spending.
Here’s a list of other rivers the organization deems at risk and what to know about them.
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#1 Colorado River
First on the list is Arizona’s Colorado River in the Grand Canyon.
According to the organization, the river has been plagued with outdated water management, over-use and of course, climate change.
This is the river’s second time topping the list.
“This year, however, the Grand Canyon is of specific focus due to severe drought,” the organization wrote. “As critical decisions are made about water management along the Colorado River, decision makers must recognize the environment as a critical component of human health and public safety – absolutely vital for the 40 million people that depend on the river for drinking water.”
Another reason the river topped the list is a smallmouth bass invasion, according to the Arizona Republic, part of the USA TODAY Network. Bass that may have slipped through the Glen Canyon Dam’s hydropower turbines from Lake Powell reproduced in the river, making things worse for already threatened humpback chubs in the Grand Canyon.
#2 Ohio River
American Rivers ranked the Ohio River at No. 2 due to pollution and climate change.
The river flows through Pennsylvania, Ohio, West Virginia, Kentucky, Indiana and Illinois.
According to the advocacy group, pollution has threatened the lives of the 5 million people who live there and rely on the river for clean water.
The organization cites industrialization and pollution threatening the upper river, exemplified by a Norfolk Southern train carrying almost 900,000 pounds of vinyl chloride, a human carcinogen, that derailed in Ohio and released chemicals into the air.
#3 Pearl River
The Pearl River in Mississippi has been threatened by the One Lake development project, American Rivers said.
According to the Associated Press, the flood project is estimated to cost $345 million and involves the dredging and excavation of the Pearl River to widen, deepen and straighten 7 miles of the river. Waterfront property could also be developed along the new 1,500-acre lake.
The project is supposed to prevent a flood like the Pearl River flood of 1979, which caused millions of dollars in damages, the National Weather Service said.
Locals have pushed back against the development project, the Associated Press reported. Concerned citizens think damming the Pearl River would decrease flow downstream and harm endangered species and oyster production.
American Rivers said the project would worsen urban flooding, exacerbate the ongoing water crisis and take away important resources from marginalized communities.
#4 Snake River
Ranking at No. 4 is the Snake River in Idaho, Oregon and Washington.
Salmon are nearly extinct in the Columbia-Snake River basin, a result of four dams that provide irrigation transportation and hydropower benefits to the Northwest, the group said.
According to the group, dam removal is vital in the protection of fish habitats and honoring commitments to nearby Tribal Nations.
#5 Clark Fork River
The Clark Fork River in Montana came in at No. 5 due to pulp mill pollution.
A former pulp mill has leaked toxic chemicals into the groundwater and increased the risk of catastrophic flooding, American Rivers said, putting public health, fish and wildlife at risk.
According to the Clark Fork Valley Press and Mineral Independent, the Clark Fork River has historically been polluted by hard rock mining, which led to heavy metal contamination in the river including copper, zinc and arsenic.
In 2020, biologist Ladd Knotek told the outlet that local trout fisheries were mostly threatened by pollution, warming water temperature and the introduction of fish like northern pike, smallmouth bass, walleye, yellow perch and sunfish.
#6 Eel River
The Eel River in California is also at risk due to dams, American Rivers said.
Similar to the Snake River, the group pushed for dam removal to protect fish habitats and maintain treaties with Tribal Nations.
Two “obsolete” dams owned by Pacific Gas and Electric harm salmon migration and river habitat, the group says.
Populations of Chinook salmon, steelhead, and Pacific lamprey are in decline on the river, the organization stated.
#7 Lehigh River
Pennsylvania’s Lehigh River ranked No. 7 on the list due to what American Rivers calls “poorly planned development” that threatens clean water, fish and wildlife habitat, rural and local communities and open space.
The development turns critical forests and wetlands into hard surfaces such as roofs and parking lots, American Rivers said.
“These impervious surfaces prevent rainwater from soaking into the ground,” the group wrote on its website. “Instead, warm, salty, dirty water runs off the pavement directly into the river and its tributaries. These impacts to water quality, and the paving of the remaining open space in the urban stretches in the Lehigh Valley, disproportionately impact downstream communities that have already borne the brunt of environmental degradation and pollution.”
#8 Chilkat and Klehini rivers
Ranking at No. 8 are Alaska’s Chilkat and Klehini rivers.
According to American Rivers, there is an ongoing development called the Palmer Project and its next phase is set to begin in summer 2023. The plan is to dig a mile-long tunnel under the Saksaia Glacier, directly above the Klehini River.
“The excavation will create huge waste storage piles and contaminated wastewater discharges in an area with extremely high levels of sulfide deposits, rainfall, snowfall, and seismic activity,” the advocacy group wrote on its website.
The group said acidic wastewater contaminated with heavy metals, hydrocarbons from vehicles and drilling muds and explosive residues will flow into creeks and the Chilkat and Klehini rivers.
The valley is home to the largest group of bald eagles in the world.
#9 Rio Gallinas
Rio Gallinas in New Mexico ranked No. 9 this year. American Rivers cited climate change as a main perpetrator threatening the river.
The river provides drinking water for 13,000 people in Las Vegas and is also a source of nutrients for plants and wildlife in the Sangre de Cristo Mountains, the Albuquerque Journal reported.
Last year, a wildfire swept through the area and destroyed 341,735 acres, American Rivers said, including part of the upper Rio Gallinas watershed.
“Community-focused, coordinated restoration efforts are imperative in protecting the future of the river,” the organization wrote.
#10 Okefenokee Swamp
Last on the list is the Okefenokee Swamp in Georgia and Florida.
Since 2019, a company called Twin Pines Minerals, LLC has sought permits to mine titanium less than 3 miles from the edge of the Okefenokee National Wildlife Refuge, reported the Savannah Morning News, part of the USA TODAY Network.
Environmental activists have said mining would lower water levels in the swamp, putting its ecosystem even more at risk due to drought and wildfires. The Okefenokee swamp is also part of the ancestral homeland of the Muscogee (Creek) Nation, which opposes the mining.
Saleen Martin is a reporter on USA TODAY’s NOW team. She is from Norfolk, Virginia – the 757 – and loves all things horror, witches, Christmas, and food. Follow her on Twitter at @Saleen_Martin or email her at sdmartin@usatoday.com.