10 Most Endangered US Rivers: 2013

Endangered Rivers

Colorado River from space

The Colorado River from space on March 12, 2013. (Image credit: NASA Earth Observatory)

The conservation group American Rivers has released its 2013 list of the most endangered rivers in the United States.

The at-risk rivers are found around the country and are threatened by factors like poor water management and mining, according to the group. Here is the list of rivers from #10 to #1, along with the threats American Rivers has documented for each and why the rivers are important to their respective ecosystems.

Niobrara River

Niobrara River

The Niobrara River, a tributary of the Missouri River. (Image credit: Niobrara River image via Shutterstock)

Location: Nebraska, South Dakota, Wyoming

Threats: Sediment build-up and flooding

The Niobrara is a tributary of the Missouri River, and its lower reaches are designated as a federal Wild and Scenic River. American Rivers says that sediment backing up behind the Missouri's Gavins Point Dam is raising the level of the Niobrara and increasing the flood threat to local communities. The group calls on the U.S. Army Corps of Engineers to better manage the sediment levels.

Kootenai River

Kootenai River

The Kootenai River, which runs through Montana, Idaho and British Columbia. (Image credit: Kootenai River image via Shutterstock)

Location: Montana, Idaho (and British Columbia in Canada)

Threats: Open-pit coal mining

The Kootenai is part of an important habitat for iconic American species like the grizzly bear and woodland caribou, as well as several rare and threatened species of fish, American Rivers says. The quality of the water and the species that depend on it are threatened by five open-pit coal mines along a tributary in British Columbia, according to the group, which calls on the U.S. State Department to work with Canada to halt the mining until impact studies can be done.

Rough & Ready and Baldface Creeks

Rough & Ready Creek

Rough & Ready Creek, a tributary to the Illinois and North Fork Smith rivers. (Image credit: Barbara Ullian)

Location: Oregon

Threats: Nickel mining

These tributaries to the Illinois and North Fork Smith rivers run with particularly clean and clear water, American Rivers says. Member of Oregon's Congressional delegation have asked the Obama administration to keep the area from being used in nickel mining, but no action has yet been taken. The conservation group says that the health of the rivers is now in the hands of Congress and the Secretaries of the Interior and Agriculture.

Black Warrior River

Black Warrior River

Aerial view of the John Hollis Bankhead Lock and Dam on the Black Warrior River in Tuscaloosa County, Ala. (Image credit: USACE)

Location: Alabama

Threats: Coal mining

The drinking water that this river provides, as well as the fishing and wildlife it supports, are threatened by a coal mine along one of its forks. American Rivers says that wastewater from the plant would be discharged just a few hundred feed from a drinking water intake. To mine the area, the company behind the proposal must lease the land from property owners, which include the University of Alabama. American Rivers asks the 8niversity to refuse to lease the land.

Boundary Waters

Boundary Waters Canoe Area Wilderness

The 1.1 million-acre Boundary Waters Canoe Area Wilderness in Minnesota. (Image credit: Boundary Waters Canoe Area Wilderness image via Shutterstock)

Location: Minnesota

Threats: Copper and nickel mining

This wilderness area is a protected region, but copper and nickel mining have been proposed on adjacent unprotected lands, the group reports. This mining could cause drainage containing heavy metals and other pollutants to flow into the protected areas, American Rivers says, and they ask that the federal and Minnesota governments block the mining proposal.

Catawba River

Catawba River

The Catawba River, which flows through North and South Carolina and provides water to millions in the Southeast. (Image credit: Catawba River image via Shutterstock)

Location: North and South Carolina

Threats: Coal ash pollution

The Catawba is an important drinking water source for the Southeast that is threatened by storage ponds for coal ash, a byproduct of power generation, American Rivers says. It asks the North Carolina Department of Environment and Natural Resources to require Duke Energy to make sure its storage ponds are well maintained to safeguard the water supply.

Little Plover River

Little Plover River

The Little Plover River in Wisconsin. (Image credit: Amy Thorstenson, Friends of the Little Plover River)

Location: Wisconsin

Threats: Outdated water management

The populations of fish that have made this river a popular fishing location are threatened by increasing withdrawals of groundwater that have lowered river levels, American Rivers says, calling on the Wisconsin Department of Natural Resources to better manage water wells.

San Saba River

San Saba River

The San Saba River in Texas. (Image credit: Robb Kendrick, National Geographic Stock)

Location: Texas

Threats: Outdated water management

Irrigation and unregulated pumping of water are threatening this pristine river, according to the conservation group. It asks the Texas Commission on Environmental Quality to enforce the laws governing these activities and the Texas Legislature to appoint a watermaster to better manage the river and its resources.

Flint River

Flint River

The Flint River below Bainbridge, Ga., showing base flow conditions. Even at low flows, rivers in this part of Georgia contain enough sediment to color the water brown. (Image credit: Brian Hughes , U.S. Geological Survey)

Location: Georgia

Threats: Outdated water management

Many of the tributaries of this river, which supplies water to more than 1 million people and 10,000 farms, have run completely dry in recent years. American Rivers itself is working to protect the river, but calls on the state government to better protect the resource.

Colorado River

Colorado River from space

The Colorado River from space on March 12, 2013. (Image credit: NASA Earth Observatory)

Location: Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming

Threats: Outdated water management

This iconic river is both a stunning part of the Western scenery, flowing through the legendary Grand Canyon, and a critical water source ¬— a "lifeline in the desert," as American Rivers said in the release on their report. But demand for water is now exceeding what the river can supply, thanks to what American Rivers calls "a century of water management policies and practices that have promoted wasteful water use." Ongoing drought in the western states and climate change are increasing the pressure on the river. The conservation group advocates more funding of programs to address the sustainability of the water supply in the Colorado River Basin.

Live Science Staff
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