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 Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

. All of these streams originate in the United States except the longest, the Columbia, which begins in the Canadian province of

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

and flows 1,249 miles (2,010 km) to the sea near Astoria. The second-longest, 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 ...

, which at is the only other stream of more than on the list, begins in

Wyoming Wyoming () is a U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the south ...

and flows through parts of

Idaho Idaho ( ) is a 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 Montana and Wyom ...

and

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 ...

, as well as Oregon. Some of the other streams also cross borders between Oregon and

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

Nevada Nevada ( ; ) is a U.S. state, state in the Western United States, Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. N ...

, Idaho, or Washington, but the majority flow entirely within Oregon. The ''Atlas of Oregon'' ranks 31 rivers in the state by average

streamflow Streamflow, or channel runoff, is the flow of water in streams and other channels, and is a major element of the water cycle. It is one component of the movement of water from the land to waterbodies, the other component being surface runoff. Water ...

; the top five are the Columbia, Snake, Willamette, Santiam, and Umpqua. Not all Oregon rivers with high average flows are on this list of longest streams because neither their

main stem In hydrology, a mainstem (or trunk) is "the primary downstream segment of a river, as contrasted to its tributaries". Water enters the mainstem from the river's drainage basin, the land area through which the mainstem and its tributaries flow.. A ...

s nor any of their

tributaries A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainage b ...

(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 Hood may refer to: Covering Apparel * Hood (headgear), type of head covering ** Article of academic dress ** Bondage hood, sex toy * Hoodie, hooded sweatshirt Anatomy * Clitoral hood, a hood of skin surrounding the clitoris * Hood, a flap of ...

, Youngs, and Coos rivers. On the other hand, the list includes four low-flow

intermittent streams A stream is a continuous body of surface water flowing within the bed and banks of a channel. Depending on its location or certain characteristics, a stream may be referred to by a variety of local or regional names. Long large streams ar ...

— 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 The Oregon Coast Range, often called simply the Coast Range and sometimes the Pacific Coast Range, is a mountain range, in the Pacific Coast Ranges physiographic region, in the U.S. state of Oregon along the Pacific Ocean. This north-south runni ...

on the west, the

Cascade Range The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, ...

further inland, the

Klamath Klamath may refer to: Ethnic groups *Klamath people, a Native American people of California and Oregon **Klamath Tribes, a federally recognized group of tribes in Oregon *Klamath language, spoken by the Klamath people Places in the United States * ...

– Siskiyou Mountains in the southwest, and the Blue Mountains in the northeast. One set of streams, including the

Nehalem River The Nehalem River is a river on the Pacific coast of northwest Oregon in the United States, approximately long. It drains part of the Northern Oregon Coast Range northwest of Portland, originating on the east side of the mountains and flowing i ...

, flows directly into the Pacific Ocean or into larger streams flowing directly to the Pacific; other streams, such as the

Deschutes River Deschutes River may refer to: *Deschutes River (Oregon) The Deschutes River in central Oregon is a major tributary of the Columbia River. The river provides much of the drainage on the eastern side of the Cascade Range in Oregon, gathering many ...

, flow into the Columbia River or its tributaries. A third set, including the

Klamath River The Klamath River (Karuk: ''Ishkêesh'', Klamath: ''Koke'', Yurok: ''Hehlkeek 'We-Roy'') flows through Oregon and northern California in the United States, emptying into the Pacific Ocean. By average discharge, the Klamath is the second larges ...

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 The Donner und Blitzen River is a river on the eastern Oregon high desert that drains a relatively arid basin, the southern portion of Harney Basin, from roughly 20 to 80 miles (30 to 130 km) south-southeast of Burns including Malheur Nation ...

flow into

closed basin An endorheic basin (; also spelled endoreic basin or endorreic basin) is a drainage basin that normally retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but drainage converges instead into lakes ...

s, such as

Malheur Lake Malheur Lake is one of the lakes in the Malheur National Wildlife Refuge in Harney County in the U.S. state of Oregon. Located about southeast of Burns, the lake is marsh fed by the Donner und Blitzen River from the south and the Silvies River ...

, that have no outlet to the sea. Source data for the table below came from

topographic map In modern mapping, a topographic map or topographic sheet is a type of map characterized by large- scale detail and quantitative representation of relief features, usually using contour lines (connecting points of equal elevation), but historic ...

s created by the

United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...

and published on-line by

TopoQuest TopoQuest is a free web mapping service built on Open-source software, open source software that provides internet-based topographic maps for most of the United States. The site is one of three internet services used by Wikipedia for providing topo ...

, and from the ''Atlas of Oregon''; the ''Oregon Atlas and Gazetteer''; two federally produced

geographic information system A geographic information system (GIS) is a type of database containing Geographic data and information, geographic data (that is, descriptions of phenomena for which location is relevant), combined with Geographic information system software, sof ...

(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).

Rivers and creeks

Map

Notes and references

;Notes ;References

Works cited

* * * * *

External links

Map of Oregon drainage basins
published by State of Oregon Water Resources Department {{featured list *Longest Streams,longest

Rivers and creeks

Map

See also

Notes and references

Works cited

External links