The Clearwater River is in the northwestern United States, in north central

Idaho Idaho ( ) is a U.S. state, state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Monta ...

. Its length is ,U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. , accessed May 3, 2011 westward from the Bitterroot Mountains along the Idaho-

Montana Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columb ...

border, and joins the

Snake River The Snake River is a major river of the greater Pacific Northwest region in the United States. At long, it is the largest tributary of the Columbia River, in turn, the largest North American river that empties into the Pacific Ocean. The Snake ...

at Lewiston. the

Lewis and Clark Expedition The Lewis and Clark Expedition, also known as the Corps of Discovery Expedition, was the United States expedition to cross the newly acquired western portion of the country after the Louisiana Purchase. The Corps of Discovery was a select gr ...

descended the Clearwater River in dugout canoes, putting in at downstream from Orofino; they reached the

Columbia Bar The Columbia Bar, also frequently called the Graveyard of the Pacific, is a system of bars and shoals at the mouth of the Columbia River spanning the U.S. states of Oregon and Washington. It is known as one of the most dangerous bar crossings in ...

and the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the conti ...

about six weeks later. By average discharge, the Clearwater River is the largest tributary of the Snake River. The River got its name for the Niimiipuutímt naming as ''Koos-Koos-Kia'' - "clear water". The

drainage basin A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, ...

of the Clearwater River is . Its mean annual

discharge Discharge may refer to Expel or let go * Discharge, the act of firing a gun * Discharge, or termination of employment, the end of an employee's duration with an employer * Military discharge, the release of a member of the armed forces from ser ...

is , Northwest Power and Conservation Council

Course

In the small town of Kooskia, the Middle Fork and South Fork of the Clearwater River join their waters to form the main stem of the Clearwater. The larger Middle Fork is made up of the combined flows of the Lochsa and Selway rivers which flow from the Bitterroot Mountains located to the east, while the much smaller South Fork originates in the Selway-Bitterroot Wilderness to the south. From the confluence, the Clearwater flows northwest, passing the Heart of the Monster site of the

Nez Perce National Historical Park The Nez Perce National Historical Park is a United States National Historical Park comprising 38 sites located across the states of Idaho, Montana, Oregon, and Washington, which include traditional aboriginal lands of the Nez Perce people. The sit ...

U.S. Route 12 U.S. Route 12 (US 12) is an east–west United States highway, running from Aberdeen, Washington, to Detroit, Michigan, for almost . The highway has mostly been superseded by Interstate 90 (I-90) and I-94, but unlike most U.S. routes that ...

follows the river to Kamiah, where Lawyer Creek from the southwest joins it. The river continues northwest through a canyon to the confluence with Lolo Creek from the east. It soon passes the town of Greer and receives Jim Ford Creek from the east. At Orofino, the river gains the waters of Orofino Creek and swings westward in a nearly straight line for about , then receives the North Fork from the northeast at Ahsahka, close to

Dworshak Reservoir Dworshak Dam is a concrete gravity dam in the western United States, on the North Fork of the Clearwater River in north central Idaho. In Clearwater County, the dam is located approximately northwest of Orofino and impounds the Dwor ...

. After the North Fork contributes its flow, the Clearwater continues west and receives Big Canyon Creek from the south and Bedrock Creek from the north. As the river canyon cuts deeper into the

Columbia Plateau The Columbia Plateau is a geologic and geographic region that lies across parts of the U.S. states of Washington, Oregon, and Idaho. It is a wide flood basalt plateau between the Cascade Range and the Rocky Mountains, cut through by the Col ...

, the Clearwater passes the unincorporated communities of Lenore and Myrtle, where it receives Cottonwood Creek from the southeast, and Arrow, where it receives the

Potlatch River The Potlatch River is in the state of Idaho in the United States. About long, it is the lowermost major tributary to the Clearwater River, a tributary of the Snake River that is in turn a tributary of the Columbia River. Once surrounded by ar ...

from the north. Lapwai Creek joins from the south, where the river passes close to Spalding. Here, U.S. Route 95 crosses the Clearwater and is co-signed with U.S. Route 12 along the river's north bank for several miles. The river soon widens and slows into the slack water of Lower Granite Lake as it approaches Lewiston. Just as it crosses the Idaho-

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

state line, it joins its waters with the Snake River.

Tributaries

The Clearwater breaks into several separate forks: * Clearwater River (west of Orofino to Lewiston-

) **

(Latah, Clearwater and Nez Perce Counties) ** North Fork Clearwater River (stream, Clearwater County - ; headwaters near Illinois Peak to just west of Orofino) *** Little North Fork Clearwater River (stream,

Shoshone The Shoshone or Shoshoni ( or ) are a Native American tribe with four large cultural/linguistic divisions: * Eastern Shoshone: Wyoming * Northern Shoshone: southern Idaho * Western Shoshone: Nevada, northern Utah * Goshute: western Utah, easte ...

& Clearwater Counties; headwaters in south-central Shoshone County, joins the North Fork in the

) ** Middle Fork Clearwater River (stream, Idaho County - ; formed by the confluence of the Selway and Lochsa at Lowell) ** South Fork Clearwater River (stream, Idaho County - ; headwaters near Red River Hot Springs to Kooskia, confluence with the Middle Fork) *** Little Clearwater River (stream, Idaho County - ; near Three Prong Mountain to near Spot Mountain)

River modifications

The Dworshak Reservoir is the only major

lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

on the Clearwater system, created from the

Dworshak Dam Dworshak Dam is a concrete gravity dam in the western United States, on the North Fork of the Clearwater River in north central Idaho. In Clearwater County, the dam is located approximately northwest of Orofino and impounds the Dwors ...

, completed in the early 1970s. Dworshak Dam is on the North Fork of the Clearwater River and is just northwest of Orofino. There is no

fish ladder A fish ladder, also known as a fishway, fish pass, fish steps, or fish cannon is a structure on or around artificial and natural barriers (such as dams, locks and waterfalls) to facilitate diadromous fishes' natural migration as well as move ...

; the dam blocks

salmon Salmon () is the common name for several commercially important species of euryhaline ray-finned fish from the family Salmonidae, which are native to tributaries of the North Atlantic (genus '' Salmo'') and North Pacific (genus '' Onco ...

and

steelhead Steelhead, or occasionally steelhead trout, is the common name of the anadromous form of the coastal rainbow trout or redband trout (O. m. gairdneri). Steelhead are native to cold-water tributaries of the Pacific basin in Northeast Asia and ...

passage.

History

The border between

and

was defined as the meridian running north from the confluence of the Clearwater River and the

. Although this border is often referred to as the

117th meridian west The meridian 117° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole. The 117th meridian west forms a great ...

longitude, the actual border line is slightly west (less than 2 miles) of the 117th meridian. Article XXIV Boundaries

References

External links