Washington (state)

I

Introduction

Washington (state), in the Pacific Northwest region of the United States. It is bordered on the north by the Canadian province of British Columbia, on the south by Oregon, on the east by Idaho, and on the west by the Pacific Ocean. Washington is the only state named for a U.S. president. It was admitted to the Union as the 42nd state on November 11, 1889. Washington has beautiful glaciated mountains and dense forests in the west, and a vast expanse of golden grainland in the eastern section of the state. Olympia is the capital of Washington. The state’s largest city, Seattle, is an important port and a gateway to East Asia and the Arctic North. However, it is the Columbia River, which carves its way down through the central part of the state before turning westward toward the Pacific Ocean, that is Washington’s most important resource.

The Columbia River is the greatest source for potential and actual hydroelectric waterpower in the United States. The construction of such great dams as Grand Coulee, Chief Joseph, and The Dalles to harness the power of this mighty river has revolutionized the state’s economy and wrought startling changes in its landscape. The Columbia’s water provides electric power for industry, most of which has come into the state during and since World War II (1939-1945), and irrigation for agriculture, especially in the drier region east of the Cascade Range, where semiarid desert land has been transformed into highly productive ranchland and farms. Washington is known as the Evergreen State, for its extensive forests of evergreen trees.

II

Physical Geography

Washington, the 19th largest state of the United States, has an area of 184,666 sq km (71,300 sq mi), including 4,022 sq km (1,553 sq mi) of inland water, and 6,571 sq km (2,537 sq mi) of coastal waters over which the state has jurisdiction. The state has an extreme length, from east to west, of 607 km (377 mi) and a maximum width, from north to south, of 385 km (239 mi). The mean elevation is about 500 m (1,700 ft).

A

Natural Regions

Washington can be divided into four major natural regions, or physiographic provinces, each of which is part of one of the larger geographic regions, or physiographic divisions, of the western United States. These four natural regions are, from west to east, the Pacific Border province, the Sierra-Cascade province, or Cascade Mountains, the Columbia Plateau, and the Northern Rocky Mountains. The Sierra-Cascade province and the Pacific Border province are subdivisions of the Pacific Mountain System. The Northern Rocky Mountains are a subdivision of the Rocky Mountain System, and the Columbia Plateau belongs to the broad region between the Rocky and Pacific mountain systems known as the Intermontane Plateaus.

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The Pacific Border province, in western Washington, includes the Olympic Mountains and Willapa Hills, which are the Washington section of the Coast Ranges, and the lowlands of the Puget Trough. The Olympic Mountains, located in northwestern Washington on the Olympic Peninsula, reach a maximum elevation of 2,428 m (7,965 ft) at Mount Olympus. However, because they rise from a dense coniferous rain forest just above sea level, they are among the most impressive peaks in the United States. The Willapa Hills, located farther south, are generally less than 900 m (less than 3,000 ft) in elevation, less densely forested, and less rugged than the Olympic Mountains.

The lowlands of the Puget Trough are part of a broad structural depression between the Coast Ranges and the Cascade Range. The northern part of the trough has been inundated by the sea to form Puget Sound; the southern part is occupied by sections of the Chehalis, Cowlitz, and Columbia river valleys.

The Sierra-Cascade province extends almost due north and south across central Washington. It has a general elevation in the north of from 1,800 to 2,400 m (6,000 to 8,000 ft), but several peaks in the south, all of them active or extinct volcanoes, rise considerably above this level. They include Mount Rainier, which rises to 4,392 m (14,410 ft) and is the highest point in Washington; Mount Adams (3,742 m/12,276 ft); and Mount Saint Helens (2,550 m/8,365 ft), which in 1980 erupted spectacularly, tearing 400 m (1,300 ft) in elevation from the peak and sending billows of ash across the state and eastward into Idaho and Montana. The western slopes of the mountains are wet and heavily forested. The east-facing slopes are cut off from rain-bearing winds and are much drier. The higher elevations are covered by glaciers and permanent snowfields.

The Columbia Plateau is a rolling, semiarid, and prairie-like region in southeastern Washington. In the southeast, just north of the Snake River, is the large wheat-growing dunelike area of the Palouse River section. West of the Palouse lie the Scablands, or Channeled Scablands, an almost barren lava plateau that was channeled, or carved, into coulees, or deep canyons, by glacial meltwaters at the end of the last Ice Age, about 10,000 years ago. The largest of the canyons are Grand Coulee and Moses Coulee. Occupying the extreme southeastern part of the Columbia Plateau are the Blue Mountains, which range up to 2,100 m (7,000 ft).

The Northern Rocky Mountains, in northeastern Washington, average from 900 to 2,100 m (3,000 to 7,000 ft) in height and are mostly forested. The principal range of the Northern Rockies in Washington is the Kettle River Range. Its tallest peaks are Copper Butte (2,175 m/7,135 ft) and Snow Peak (2,165 m/7,103 ft).

B

Coastline

Washington has an overall coastline of only 253 km (157 mi) and a detailed coastline, which includes the shoreline of all bays, indentations, and islands, of 4,870 km (3,026 mi). The principal indentation is Puget Sound, which is connected with the Pacific Ocean by the Strait of Juan de Fuca. More than 300 islands, including the San Juan Islands, and a number of rocky protuberances, stud the sound and confine navigation to defined channels. Other major indentations are Willapa Bay and Grays Harbor. Long sandy beaches border the southwestern coast between the bays. The ocean side of the Olympic Peninsula is bordered by rugged cliffs and headlands.

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