The 10 Most Endangered Rivers of 2015
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1. The Colorado River in the Grand Canyon (Arizona, Utah)
Threat: Harmful development, groundwater depletion, uranium mines
At risk: An irreplaceable natural and cultural treasure
Photo: Millions of Americans recognize the Grand Canyon as one of the most iconic landscapes on the planet. But this natural masterpiece of the Colorado River faces a battery of threats. A proposed tram development in the heart of the canyon, uranium mining, and a proposed expansion of the town of Tusayan that could deplete vital groundwater supplies. Unless the Department of the Interior acts to stop these threats, one of our nation’s greatest natural treasures will be scarred forever.
2. Columbia River (Washington, Oregon)
Threat: Outdated dam operations
At risk: Healthy salmon runs, flood protection
The Columbia River is the lifeblood of the Pacific Northwest’s economy and environment. The river’s dams provide more than half the region’s electricity as well as flood control, but they have also decimated the basin’s salmon and steelhead runs. As the U.S. and Canada begin renegotiating the Columbia River Treaty this year (the last negotiation took place 60 years ago), the State Department is being pressured to put the importance of a healthy ecosystem on an equal footing with the benefits of hydropower and flood control.
3. Holston River (Tennessee)
Threat: Toxic chemical pollution
At risk: Drinking water supply, fish and wildlife, recreation
The Holston River is rich in history and heritage and provides drinking water for tens of thousands of Virginia and Tennessee residents, as well as water for industry, livestock, and recreation. However, the river and its communities are threatened by chemical pollution from an army ammunition plant that has been contaminating water supplies for years.
4. Smith River (Montana)
Threat: Copper mine
At risk: Water quality, wild trout fishery
The Smith River is one of the most cherished floating and fishing destinations in Montana. The river is home to a nationally-renowned wild trout fishery, and provides prime habitat for dozens of beloved wildlife species. The river is threatened by a proposed copper mine in its headwaters that could seriously degrade water quality with acid mine drainage and toxic heavy metals.
5. Edisto River (South Carolina)
Threat: Excessive water withdrawals
At risk: Water supply, water quality, fish and wildlife habitat, recreation
The Edisto River is one of South Carolina’s most popular rivers for paddling, fishing, and outdoor fun. It’s also the state’s most heavily used river for irrigation, and excessive agricultural water withdrawals are threatening water quality and the water supplies of other users. While the state’s permitting process requires industrial and municipal water users to meet requirements to safeguard river health and clean water, large agribusinesses get a pass. The South Carolina House of Representatives has an opportunity to pass a law, H.3564, this year to end this exemption so that the Edisto—and all of the state’s rivers—can continue to provide sustainable water supplies while supporting river health and recreation.
6. Chuitna River (Alaska)
Threat: Coal mine
At risk: Native culture, wild salmon, clean water
Alaska’s Chuitna River supports Alaskan Native communities, all five species of wild Pacific salmon; abundant wildlife including moose, bear, and wolf; and excellent opportunities for hunting, fishing, and other recreation. PacRim Coal’s proposal to develop Alaska’s largest open-pit coal strip mine at the Chuitna River’s headwaters poses a threat to the economy and communities that rely on clean water and healthy salmon runs.
7. Rogue-Smith Watersheds (Oregon, California)
Threat: Nickel mines
At risk: Clean water, Wild and Scenic Rivers
The Wild and Scenic Illinois (OR), Rogue (OR), and Smith River (OR and CA) watersheds are known for their pristine waters, healthy salmon runs, globally significant plant biodiversity, and outstanding recreation. But proposed nickel mining in the rivers’ headwaters threatens these unique values.
8. St. Louis River (Minnesota)
Threat: Copper-nickel sulfide mine
At risk: Clean water and wildlife habitat
Minnesota’s Arrowhead region is known for its pure and abundant waters, deep forests, expansive wetlands, and recreational opportunities. However, a proposed copper-nickel sulfide mine at the headwaters of the St. Louis River, the region’s main artery, threatens drinking water, wildlife, and treaty-protected hunting, fishing, and gathering rights of the Ojibwe people and all of region’s citizens.
9. Harpeth River (Tennessee)
Threat: Sewage pollution
At risk: Clean water, fish and wildlife, recreation
The Harpeth River is one of the few free-flowing rivers in Tennessee. It is an oasis for local families, anglers, and boaters in one of the fastest growing regions of the country. But pollution from outdated sewage treatment facilities threatens the river’s clean water, fish and wildlife, and recreation. Unless state officials require state-of-the-art technology to improve sewage treatment, the river will be contaminated with sewage pollution and public health could be compromised.
10. Pearl River (Louisiana, Mississippi)
Threat: New dam
At risk: Healthy wetlands, fish and wildlife habitat
The Pearl River runs through Central Mississippi and supports vital oyster reefs and marsh habitat in the Mississippi Sound. Coastal wetlands and commercial fisheries depend on the Pearl River’s flows, but the river’s health has been compromised by the Barnett Dam north of Jackson, Mississippi. Now, a new dam is proposed for the Pearl that would cause additional harm to river health, wetlands, and fish and wildlife habitat.