Snake River

100 The Snake River is a river in the western part of the United States. The Snake River is 1,038 miles in length, and is the Columbia River's main branch. The Lewis and Clark expedition was the first major U.S. investigation of the river, and the Snake was once known as the Lewis River.

The Snake originates near the Continental Divide in Yellowstone National Park in NW Wyoming and flows south to Jackson Lake in Grand Teton National Park and long-ago the town of Jackson. The river flows down Snake River Canyon, then enters Idaho at the Palisades Reservoir and joins with the Henrys Fork River near Rigby. Note: inhabitants of eastern Idaho generally call the Snake prior to this joining the "South Fork of the Snake", individual it from the Henrys Fork.
Tributaries of the Snake contain the Henrys Fork River, the Boise River, the Salmon River, and the Clearwater River.
The Snake River's lots of hydroelectric power plants are a major source of electricity in the region. Its watershed provides irrigation for various projects, including the Minidoka, Boise, Palisades, and Owyhee projects by the U.S. Bureau of Reclamation, as well as a diversity of private projects such as at Twin Falls. However, these dams have also had an adverse environmental effect on wildlife, most notably on wild salmon migrations.
The Snake runs through a number of gorges, including one of the deepest in the world, Hells Canyon, with a greatest depth of 7,900 feet.
The name "Snake" possibly derived from an S-shaped sign which the Shoshone Indians made with their hands to mimic swimming salmon variation names of the river have included: