Portneuf River (Idaho)

The Portneuf River is a tributary of the Snake River, approximately convert|96|mi|km long, in southeastern Idaho in the United States. It drains a ranching and farmer valley in the mountains southwest of the Snake River Plain near the Utah border. The city of Pocatello sits along the river near its emergence from the mountains onto the Snake River Plain.

The river is part of the Columbia River Basin.

Course

The Portneuf River rises in western Caribou County, approximately convert|25|mi|km east of Pocatello, along the eastern side of the Portneuf Range. It flows initially south, passing westward around the southern end of the range, and then turning north to flow between the Portneuf Range to the east and the Bannock Range. It flows northwest through downtown Pocatello and enters the Snake at the northeast corner of American Falls Reservoir, approximately convert|10|mi|km northwest of Pocatello.

Watershed and discharge

The Portneuf River's drainage basin is approximately convert|1329|sqmi|km2|0 in area. [http://www.nwcouncil.org/fw/subbasinplanning/uppersnake/plan/Assessment/1IntroOverview.pdf Upper Snake, Headwaters, Closed Basin Subbasins Plan Plan] , Northwest Power and Conservation Council]

Its mean annual discharge, as measured at by USGS gage 13075910 (Portneuf River at Tyhee, ID), is convert|418|cuft/s|sigfig=3, with a maximum daily recorded flow of convert|1730|cuft/s|sigfig=3|abbr=on, and a minimum of convert|32|cuft/s|sigfig=3|abbr=on. [http://pubs.usgs.gov/wdr/2005/wdr-id-05-1/pdf/ID05v1-09.pdf Upper Snake River basin between Idaho Falls and Neeley (includes Willow Creek, Blackfoot and Portneuf River basins)] , Water Resources Data, Idaho, 2005]

History

The Portneuf River was given its name sometime before 1821 by French Canadian voyageurs working for the Montreal-based fur trading North West Company. [cite book |last= Mackie |first= Richard Somerset |title= Trading Beyond the Mountains: The British Fur Trade on the Pacific 1793-1843 |year= 1997 |publisher= University of British Columbia (UBC) Press |location= Vancouver |isbn= 0-7748-0613-3 |pages= p. 26]

The valley of the Portneuf provided the route of the Oregon Trail and California Trail in the middle 19th century. After the discovery of gold in Idaho, it became a significant stage route for the transportation of people and goods. In 1877 the valley was used as the route of the Utah and Northern Railway, the first railroad in Idaho.

ee also

*List of rivers of Idaho
*Tributaries of the Columbia River

References

External links