Seventy-seven rivers and creeks of at least 50 miles (80 km) in total length are the longest streams of the U.S. state of
Oregon. All of these streams originate in the United States except the longest, the
Columbia, which begins in the Canadian province of
British Columbia and flows 1,249 miles (2,010 km) to the sea near
Astoria. The second-longest, the
Snake River, which at 1,078 miles (1,735 km) is the only other stream of more than 1,000 miles (1,600 km) on the list, begins in
Wyoming and flows through parts of
Idaho and
Washington, as well as Oregon. Some of the other streams also cross borders between Oregon and
California,
Nevada, Idaho, or Washington, but the majority flow entirely within Oregon.
The Atlas of Oregon ranks 31 rivers in the state by average
streamflow; the top five are the Columbia, Snake,
Willamette,
Santiam, and
Umpqua.[1] Not all Oregon rivers with high average flows are on this list of longest streams because neither their
main stems nor any of their
tributaries (including what are called "forks") are at least 50 miles (80 km) long. High-flow streams mentioned in the Atlas but not included in this long-stream list are the
Metolius,
Hood,
Youngs, and
Coos rivers. On the other hand, the list includes four low-flow
intermittent streams—
Dry River,
Rattlesnake Creek,
Rock Creek, and
Dry Creek—that cross parts of the
Oregon High Desert.
The direction of Oregon stream flow is influenced by four major drainage divides: the
Oregon Coast Range on the west, the
Cascade Range further inland, the
Klamath–
Siskiyou Mountains in the southwest, and the
Blue Mountains in the northeast. One set of streams, including the
Nehalem River, flows directly into the Pacific Ocean or into larger streams flowing directly to the Pacific; other streams, such as the
Deschutes River, flow into the Columbia River or its tributaries. A third set, including the
Klamath River and its tributaries, originates in Oregon, but its waters eventually flow into northern California before reaching the ocean. Other streams like the
Donner und Blitzen River flow into
closed basins, such as
Malheur Lake, that have no outlet to the sea.[1]
Source data for the table below came from
topographic maps created by the
United States Geological Survey and published on-line by
TopoQuest,[2] and from the Atlas of Oregon;[1] the Oregon Atlas and Gazetteer;[3] two federally produced
geographic information system (GIS) datasets—the National Hydrography Dataset and the National Watershed Boundary Dataset—and other sources as noted. In the table, total lengths are given in miles (mi) and kilometers (km), and elevations are in feet (ft) and meters (m).
^Only 307 miles (494 km) of the Columbia River flow through Oregon.[8]
^Only 235 miles (378 km) of the Snake River flow through Oregon.[12]
^Only 198 miles (319 km) of the Owyhee River flow through Oregon.[14]
^Only 46 miles (74 km) of the Klamath River flow through Oregon.[18]
^Only about 144 miles (232 km) of the Grande Ronde River flow through Oregon. The river leaves Oregon and enters Washington at about
river mile 39, reenters Oregon at river mile 38, and flows back into Washington at river mile 37. The distance within Oregon is the total length, 182 miles (293 km), minus the distance 38 miles (61 km) in Washington.[31]
^Only 52 miles (84 km) of Jordan Creek flow through Oregon. The creek enters Oregon at about river mile 52.[11]
^Only 39 miles (63 km) of Succor Creek flow through Oregon. The creek enters Oregon at about river mile 44 and leaves it at about river mile 5.[11]
^Only about 46 miles (74 km) of the Lost River flow through Oregon. The river enters Oregon at about
river mile 48 and leaves it at about river mile 2.[119]
^About 50 miles (80 km) of the Applegate River flow through Oregon. This is the sum of the 46 miles (74 km) marked on topo maps plus the remaining distance to the California border, measured by map scale and ruler.[157]
^Only 36 miles (58 km) of Cow Creek flow through Oregon. The creek enters Oregon at about river mile 36.[11]
^Only about 10 miles (16 km) of the Walla Walla River flow through Oregon. The river leaves the state and enters Washington at about
river mile 40.[171]
^
abBased on information in
United States Geological Survey maps published on the Internet by
TopoQuest, the Oregon Atlas, and the Oregon Atlas & Gazetteer. Locations are in Oregon except as noted.
^"Willamette River". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved August 6, 2010.
^United States Geological Survey (August 9, 2011).
United States Geological Survey Topographic Map (Topographic map). Reston, VA: United States Geological Survey. Retrieved August 9, 2011 – via TopoQuest.
^"Crooked River". Geographic Names Information System. United States Geological Survey (USGS). November 28, 1980. Retrieved August 16, 2010.
^Length derived by subtracting the main stem length of 187 miles (301 km) from the United States Geological Survey figure of 309 miles (497 km) for the main stem plus the Middle Fork
^"Middle Fork Willamette River". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved August 9, 2010.
^"Silvies River". Geographic Names Information System (GNIS). United States Geological Survey (USGS). November 28, 1980. Retrieved August 14, 2010.
^"North Fork John Day River". Geographic Names Information System (GNIS). United States Geological Survey (USGS). November 28, 1980. Retrieved August 15, 2010.
^"McKenzie River". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved August 7, 2010.
^Harney County Watershed Council (May 2000).
"Silver Creek Subbasin Assessment"(PDF). Oregon Water Resources Department. p. 2.
Archived(PDF) from the original on May 26, 2017. Retrieved May 23, 2017.
^"Silver Creek". Geographic Names Information System. United States Geological Survey. November 28, 1980. Retrieved August 5, 2010.
^
abMcDowell, P.F.; O'Connor, J.E.; Lind, P. (2005). Sprague River geomorphology studies, Klamath Basin, Oregon (abstract #H31H-06) (Report). The Smithsonian/NASA Astrophysics Data System (Smithsonian Astrophysical Observatory).
Bibcode:
2005AGUFM.H31H..06M. Retrieved April 11, 2011.
^"Sprague River". Geographic Names Information System. United States Geological Survey (USGS). November 28, 1980. Retrieved August 16, 2010.
^Taylor, Barbara (1999).
"Indian Use"(PDF). Salmon and Steelhead Runs and Related Events of the Clackamas River Basin: A Historical Perspective. Portland General Electric. p. 5. Archived from
the original(PDF) on March 11, 2006. Retrieved August 6, 2010.
^"Clackamas River, Oregon". Geographic Names Information System. United States Geological Survey. 1980. Retrieved August 7, 2010.
^
abTualatin River Watershed Council.
"Frequently Asked Questions". Tualatin River Watershed Council. Archived from
the original on July 17, 2012. Retrieved August 6, 2010.
^"Tualatin River". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved August 6, 2010.
^"Rock Creek". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved September 3, 2010.
^"Donner und Blitzen River". Geographic Names Information System. United States Geological Survey (USGS). November 28, 1980. Retrieved August 16, 2010.
^"South Fork Crooked River". Geographic Names Information System. United States Geological Survey (USGS). November 28, 1980. Retrieved September 3, 2010.
^"Middle Fork John Day River". Geographic Names Information System. United States Geological Survey. November 28, 1980. Retrieved August 12, 2010.
^United States Geological Survey (USGS).
"United States Geological Survey Topographic Map". TopoQuest. Retrieved August 24, 2010. The maps include
river mile markers for the lower 73 miles (117 km) of the river. The remaining distance is an estimate based on map scale and ruler.
^"West Little Owyhee River". Geographic Names Information System. United States Geological Survey (USGS). November 28, 1980. Retrieved August 31, 2010.
^Bully Creek Watershed Coalition; et al. (1997).
"Bully Creek Watershed Assessment and Strategy"(PDF). Oregon Department of Fish and Wildlife. p. 9.
Archived(PDF) from the original on May 22, 2017. Retrieved October 3, 2015.
^"Bully Creek". Geographic Names Information System. United States Geological Survey. November 28, 1980. Retrieved August 27, 2010.
^"South Fork John Day River". Geographic Names Information System (GNIS). United States Geological Survey (USGS). November 28, 1980. Retrieved August 12, 2010.
^"Lost River". Geographic Names Information System. United States Geological Survey (USGS). November 28, 1980. Retrieved August 16, 2010.
^United States Geological Survey.
"United States Geological Survey Topographic Map". TopoQuest. Retrieved August 8, 2010. The map quadrants include
river mile (RM) markers from the mouth to RM 55 (river kilometer 89), upstream of
Grand Ronde, Oregon. The remaining distance is an estimate based on map scale and ruler.
^"Map 1: The Yamhill River Basin & the Chehalem Valley"(PDF). Yamhill Basin Council. 2002. Archived from
the original(PDF) on December 26, 2004. Retrieved August 9, 2011. The total is the sum of five subwatersheds: Upper Yamhill, Mill Creek, Salt Creek, Lower South Yamhill/Deer Creek, and Willamina Creek.
^"South Yamhill River". Geographic Names Information System. United States Geological Survey. November 28, 1980. Retrieved August 9, 2010.
^"North Fork Malheur River". Geographic Names Information System. United States Geological Survey. November 28, 1980. Retrieved August 26, 2010.
^
abAme, John (2007).
"Yaquina Watershed". Oregon State University. Retrieved October 17, 2010.
^"Yaquina River". Geographic Names Information System (GNIS). United States Geological Survey (USGS). November 28, 1980. Retrieved August 14, 2010.
^
abMaudlin, Michael (December 2000).
"Umatilla Sub-Basin Assessment"(PDF). Washington State University. Archived from
the original(PDF) on July 20, 2011. Retrieved August 24, 2010.
^"Butter Creek". Geographic Names Information System (GNIS). United States Geological Survey (USGS). November 28, 1980. Retrieved August 24, 2010.
^"Rattlesnake Creek". Geographic Names Information System (GNIS). United States Geological Survey (USGS). November 28, 1980. Retrieved September 3, 2010.
^"Malheur River Basin Agricultural Water Quality Management Area Plan"(PDF). Oregon Department of Agriculture. February 15, 2001. p. 9. Archived from
the original(PDF) on June 9, 2011. Retrieved March 5, 2011. Reference states that Willow Creek is dammed 41 miles (66 km) from its mouth. The remaining distance is an estimate based on map scale and ruler.
^"Long Tom River". Geographic Names Information System (GNIS). United States Geological Survey (USGS). November 28, 1980. Retrieved September 3, 2010.
^Clark, Jennifer Shannon (March 7, 2003).
"Fifteenmile Watershed Assessment"(PDF). Wasco County Soil and Water Conservation District. Retrieved May 22, 2017.
^"Fifteenmile Creek". Geographic Names Information System (GNIS). United States Geological Survey (USGS). November 28, 1980. Retrieved September 3, 2010.
^"Dry Creek". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved March 13, 2011.
^United States Geological Survey (USGS).
"United States Geological Survey Topographic Map". TopoQuest. Retrieved August 17, 2010. Map quadrangles show river mileage from the mouth to 49.7 miles (80.0 km). The remaining distance is an estimate based on map scale and ruler.
^"Nestucca River". Geographic Names Information System. United States Geological Survey (USGS). November 28, 1980. Retrieved August 16, 2010.
^"Warm Springs River". Geographic Names Information System. United States Geological Survey (USGS). November 28, 1980. Retrieved September 3, 2010.
^"North Fork Coquille River". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved August 25, 2010.
^"Chewaucan River". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved September 3, 2010.
^
ab"United States Geological Survey Topographic Map". Geographic Names Information System. TopoQuest. Retrieved August 17, 2010. Map quadrants show river mileage from the mouth to river mile (RM) 46 or river kilometer (RK) 74 near the intake for Applegate Dam. The remaining distance is an estimate based on map scale and ruler.
^"Crooked Creek". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved September 3, 2010.
^"Minam River Spring Chinook Population"(PDF). Northwest Fisheries Science Center of the National Oceanic and Atmospheric Administration. p. 2. Archived from
the original(PDF) on March 4, 2016. Retrieved August 17, 2010.
^"Minam River". Geographic Names Information System (GNIS). United States Geological Survey (USGS). November 28, 1980. Retrieved August 16, 2010.
^United States Geological Survey.
"United States Geological Survey Topographic Map". TopoQuest. Retrieved August 9, 2010. The map quadrants include river mile (RM) markers from the mouth to RM 46.3 (river kilometer 74.5). The remaining distance is an estimate based on map scale and ruler.
^"Molalla River". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved August 9, 2010.
^
abUnited States Geological Survey (USGS).
"United States Geological Survey Topographic Map". TopoQuest. Retrieved August 18, 2010. The maps include
river mile markers for the lower 46 miles (74 km) of the river. The remaining distance is an estimate based on map scale and ruler.
^"Walla Walla River". Geographic Names Information System (GNIS). United States Geological Survey (USGS). November 28, 1980. Retrieved August 14, 2010.
Works cited
Allan, Stuart; Buckley, Aileen R.; Meacham, James E. (2001) [1976]. Loy, William G. (ed.). Atlas of Oregon (2 ed.). Eugene, Oregon: University of Oregon Press.
ISBN978-0-87114-101-9.
Carter, James L.; Resh, Vincent H. (2005a). "Chapter 12: Pacific Coast Rivers of the Coterminous United States". In Benke, Arthur C.; Cushing, Colbert E. (eds.). Rivers of North America. Burlington, Massachusetts: Elsevier Academic Press.
ISBN978-0-12-088253-3.
Palmer, Tim (2014). Field Guide to Oregon Rivers. Corvallis, Oregon: Oregon State University Press.
ISBN978-0-87071-627-0.
Sheehan, Madelynne Diness (2005). Fishing in Oregon: The Complete Oregon Fishing Guide (10th ed.). Scappoose, Oregon: Flying Pencil Publications.
ISBN978-0-916473-15-0.
Stanford, Jack A.; Gregory, Stanley V.; Hauer, F. Richard; Snyder, Eric B. (2005b). "Chapter 13: Columbia River Basin". In Benke, Arthur C.; Cushing, Colbert E. (eds.). Rivers of North America. Burlington, Massachusetts: Elsevier Academic Press.
ISBN978-0-12-088253-3.