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33-581: The headwaters of the Walla Walla River lie in the Blue Mountains of northeastern Oregon . The river originates as the North and South Forks of the Walla Walla River. The surrounding forested land holds a network of hiking and mountain-biking trails. The confluence of the North and South Forks lies east of Milton–Freewater , Oregon. The river flows eastward to reach Milton–Freewater, which

66-822: A mountain range in the northwestern United States , located largely in northeastern Oregon and stretching into extreme southeastern Washington . The range has an area of about 15,000 square miles (39,000 km ), stretching east and southeast of Pendleton, Oregon , to the Snake River along the Oregon– Idaho border. The Blue Mountains cover ten counties across two states; they are Union , Umatilla , Grant , Baker , Wallowa and Harney counties in Oregon, and Walla Walla , Columbia , Garfield and Asotin counties in Washington. The Blue Mountains were named after

99-538: Is at work while the mountains are being uplifted until the mountains are reduced to low hills and plains. The early Cenozoic uplift of the Rocky Mountains of Colorado provides an example. As the uplift was occurring some 10,000 feet (3,000 m) of mostly Mesozoic sedimentary strata were removed by erosion over the core of the mountain range and spread as sand and clays across the Great Plains to

132-558: Is built along its banks, and then flows northward through Milton–Freewater. Irrigation water is drawn from the river here and at numerous locations along the river. The Walla Walla River flows southwest of the city of Walla Walla in the Walla Walla valley. Mill Creek , which flows through the city of Walla Walla, joins the Walla Walla River at the Whitman Mission west of the city of Walla Walla. The Touchet River joins

165-466: Is called Wallula Lake, the reservoir impoundment created by McNary Dam . The Walla Walla tribe occupied the region around the Walla Walla river prior to white settlers entry to the region. The Lewis and Clark Expedition (1804–1806) was the first United States overland expedition to the Pacific coast and back—the return expedition stopped at the mouth of the Walla Walla and stayed with

198-610: Is located along the south-eastern flank of the range. U.S. Route 26 crosses the southern portion of the range, traversing the Blue Mountain Summit and reaching an elevation of 5,098 feet (1,554 m). It is also crossed by the Union Pacific Railroad 's mainline between Portland, Oregon, and Pocatello, Idaho, which crests the summit at Kamela, Oregon . The summit lies on Union Pacific's La Grande Subdivision, which runs between La Grande and Hinkle ,

231-865: The Alpide belt . The Pacific Ring of Fire includes the Andes of South America, extends through the North American Cordillera , the Aleutian Range , on through Kamchatka Peninsula , Japan , Taiwan , the Philippines , Papua New Guinea , to New Zealand . The Andes is 7,000 kilometres (4,350 mi) long and is often considered the world's longest mountain system. The Alpide belt stretches 15,000 km across southern Eurasia , from Java in Maritime Southeast Asia to

264-551: The Annamite Range . If the definition of a mountain range is stretched to include underwater mountains, then the Ocean Ridge forms the longest continuous mountain system on Earth, with a length of 65,000 kilometres (40,400 mi). The position of mountain ranges influences climate, such as rain or snow. When air masses move up and over mountains, the air cools, producing orographic precipitation (rain or snow). As

297-600: The Columbia . The southernmost portion of the Blue Mountains is drained by the Silvies River , in the endorheic Harney Basin . Mountain range A mountain range or hill range is a series of mountains or hills arranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have arisen from

330-804: The Iberian Peninsula in Western Europe , including the ranges of the Himalayas , Karakoram , Hindu Kush , Alborz , Caucasus , and the Alps . The Himalayas contain the highest mountains in the world, including Mount Everest , which is 8,848 metres (29,029 ft) high. Mountain ranges outside these two systems include the Arctic Cordillera , Appalachians , Great Dividing Range , East Siberians , Altais , Scandinavians , Qinling , Western Ghats , Vindhyas , Byrrangas , and

363-891: The North Fork John Day Wilderness , the Strawberry Mountain Wilderness , and the Monument Rock Wilderness , all of which are in Oregon. The Wenaha–Tucannon Wilderness sits astride the Oregon–Washington border. The range is drained by several rivers, including the Grande Ronde and Tucannon , tributaries of the Snake, as well as the forks of the John Day , Umatilla and Walla Walla rivers, tributaries of

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396-921: The Ochoco Mountains and Maury Mountains in the west near Prineville, Oregon , through the Greenhorn Mountains , the Aldrich Mountains , and the Strawberry Range , to the Elkhorn Mountains . The tallest peaks are Rock Creek Butte at 9,106 feet (2,776 m) in the Elkhorn Mountains, and Strawberry Mountain at 9,042 feet (2,756 m) in the Strawberry Range. The ranges of the Blue Mountains were uplifted by folding upward into

429-766: The Oregon Trail and were often the last mountain range American pioneers had to cross before either reaching southeast Washington near Walla Walla or passing down the Columbia River Gorge to the end of the Oregon Trail in the Willamette Valley near Oregon City . The range is currently traversed by Interstate 84 , which crosses the crest of the range at a 4,193-foot (1,278 m) summit, from south-southeast to north-northwest between La Grande and Pendleton. The community of Baker City

462-704: The "Blue Mountain Anticline" by tectonic rotation that began about 14 million years ago. More limited faulting and extension in places that include Baker valley and the Grande Ronde valley also contributed to today's topography. The Wallowa Mountains are considered to be part of the Blues by many geologists because their geology includes the same accreted terranes as the Elkhorns, Greenhorns, and Strawberries, although their mechanism of uplift differs somewhat. Similarly,

495-483: The Blue Mountains were inhabited by several different bands of the Northern Paiute , a Great Basin culture. Native American tribes originally migrated to the Blue Mountains for hunting and salmon runs. The Natives used to purposefully burn small parts of the forest in order to create pastures to attract game for hunting. In the mid-1800s, the Blue Mountains were a formidable obstacle to settlers traveling on

528-869: The United States Forest Service and the Bureau of Land Management public agencies, but also by private land owners and the Confederated Tribes of the Umatilla Indian Reservation. Much of the range is included in the Malheur National Forest , Umatilla National Forest , and Wallowa–Whitman National Forest . Several wilderness areas encompass remote parts of the range, including the North Fork Umatilla Wilderness ,

561-624: The Walla Walla River & the overall catchment area has produced a wide range of studies. The Walla Walla Basin Watershed Council (WWBWC www.wwbwc.org) has both electronic and paper copies of many of these reports that date back to the 1930s. Considerable work has gone into the assessment of water quantity and quality for the purpose of salmon recovery and sustainable irrigation supply. A highly-connected alluvial groundwater system and its over-abstraction through over-allocated irrigation usage have also acted to influence flows and quality in

594-593: The Walla Walla River. The promise of the Walla Walla River lies in its integrated water-management strategy using Managed Aquifer Recharge (Or Shallow Aquifer Recharge) to utilise available non-irrigation season water to replenish groundwater supplies and the over-allocation of groundwater resources by both state governments. The Walla Walla partnership along with the WWBWC set a national example with this innovative and low-cost alternative to surface storage using dams. Blue Mountains (Oregon) The Blue Mountains are

627-588: The Walla Walla at the town of Touchet, Washington . The annual mean discharge of the Walla Walla River just below the Touchet River confluence is 589 cu ft/s (16.7 m/s). The maximum recorded discharge was 33,400 cu ft/s (950 m/s) in 1964. The river enters the Columbia a mile south of the town of Wallula just north of Wallula Gap . The section of the Columbia River

660-542: The Walla Walla tribe for a portion of the journey, proceeding from there overland to the Snake River . British explorer David Thompson was the first European to navigate the entire length of the Columbia River, to the Pacific Ocean, in 1811. Fort Nez Percés (later known as Fort Walla Walla ) was a fortified fur trading post on the Columbia River on the territory of modern-day Wallula, Washington. It

693-627: The air descends on the leeward side, it warms again (following the adiabatic lapse rate ) and is drier, having been stripped of much of its moisture. Often, a rain shadow will affect the leeward side of a range. As a consequence, large mountain ranges, such as the Andes, compartmentalize continents into distinct climate regions . Mountain ranges are constantly subjected to erosional forces which work to tear them down. The basins adjacent to an eroding mountain range are then filled with sediments that are buried and turned into sedimentary rock . Erosion

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726-601: The color of the mountains when seen from a distance and the blue hue imparted by the smoke of forest and range fires set by Indigenous people as management tools in the fall. The Blue Mountains are unique as the home of the world's largest living organism, a subterranean colonial mycelial mat of the fungus Armillaria ostoyae . The Blues are uplift mountains and contain some of the oldest rocks in Oregon. Rocks as old as 400 million years protrude through surrounding Columbia River Basalt flows and related volcanics of 16.7 million to about 6 million years ago. Geologically ,

759-485: The east. This mass of rock was removed as the range was actively undergoing uplift. The removal of such a mass from the core of the range most likely caused further uplift as the region adjusted isostatically in response to the removed weight. Rivers are traditionally believed to be the principal cause of mountain range erosion, by cutting into bedrock and transporting sediment. Computer simulation has shown that as mountain belts change from tectonically active to inactive,

792-738: The geology of Hells Canyon and the Seven Devils Mountains is also composed of accreted terranes of a similar nature. The river valleys and lower levels of the range were occupied by indigenous peoples for thousands of years. Historic tribes of the region included the Walla Walla , Cayuse people and Umatilla , now acting together as the Confederated Tribes of the Umatilla Indian Reservation , located mostly in Umatilla County, Oregon. The southern portion of

825-565: The latter of which is the site of a major UP yard. Birds of the area include bald eagle , Lewis's woodpecker , Williamson's sapsucker , red-breasted nuthatch , golden-crowned kinglet and many migratory species, with the riverbanks important habitat for this birdlife. Mammals that move through the mountain grasslands include Rocky Mountain elk , Bighorn sheep and Mule deer . Native fish include Chinook Salmon, Steelhead, Redband Trout, Bull Trout, and Pacific Lamprey. The Blue Mountains in Washington are home to one of 10 identified elk herds in

858-415: The mid 1990s the area then became known for its mature males and trophy hunting. In 2018, Washington State proposed an updated elk management plan intended to improve the health of elk populations and habitats, reduce human conflict and agricultural damage, and managing elk populations for recreational, educational, scientific, and ceremonial purposes. The lands in the Blue Mountains are managed not only by

891-466: The oldest rocks of the Blue Mountains (400+ to about 150 million years in age) were created as island arcs in the Pacific Ocean and accreted onto the North American plate . Today, this suture zone runs through Western Idaho (Riggins and McCall) Within these terranes are igneous intrusions , some of which have intruded after accretion. The Blue Mountains include several mountain ranges, from

924-627: The rate of erosion drops because there are fewer abrasive particles in the water and fewer landslides. Mountains on other planets and natural satellites of the Solar System, including the Moon , are often isolated and formed mainly by processes such as impacts, though there are examples of mountain ranges (or "Montes") somewhat similar to those on Earth. Saturn 's moon Titan and Pluto , in particular, exhibit large mountain ranges in chains composed mainly of ices rather than rock. Examples include

957-502: The same cause, usually an orogeny . Mountain ranges are formed by a variety of geological processes, but most of the significant ones on Earth are the result of plate tectonics . Mountain ranges are also found on many planetary mass objects in the Solar System and are likely a feature of most terrestrial planets . Mountain ranges are usually segmented by highlands or mountain passes and valleys . Individual mountains within

990-531: The same mountain range do not necessarily have the same geologic structure or petrology . They may be a mix of different orogenic expressions and terranes , for example thrust sheets , uplifted blocks , fold mountains, and volcanic landforms resulting in a variety of rock types . Most geologically young mountain ranges on the Earth's land surface are associated with either the Pacific Ring of Fire or

1023-571: The state, with a population of approximately 4,500 Rocky Mountain elk as of 2018 across the region. In 1989, in response to a decline in the elk population and a heavy female-biased population, the Washington Fish & Wildlife Department regulated elk hunting in the Washington Blue Mountains with a "spike-only" general hunting season, permitting hunting of only male elk with at least one visible non-branched antler. By

Walla Walla River - Misplaced Pages Continue

1056-501: Was established in 1836. It lies near the banks of the river to the west of the modern city of Walla Walla. The Walla Walla River supports populations of spring Chinook salmon , summer steelhead , and bull trout among other species. There is a sport fishery for steelhead in the river. It also holds channel catfish and smallmouth bass in the summer. Work done by Oregon and Washington State governments, federal and state environmental agencies and local watershed councils and groups on

1089-571: Was in operation from 1818 until 1857 on the eastern shore of the Columbia River, immediately north of the mouth of the Walla Walla River. The Oregon Treaty ended joint U.S.A. - British occupation that had been effect since the Treaty of 1818 . The fort was abandoned in 1857 when the Hudson's Bay Company gave up its Columbia District business in the Oregon Territory . The Whitman Mission

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