Lake Washington is a large freshwater

lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

adjacent to the city of

Seattle Seattle ( ) is a seaport city on the West Coast of the United States. It is the seat of King County, Washington. With a 2020 population of 737,015, it is the largest city in both the state of Washington and the Pacific Northwest regio ...

. It is the largest lake in King County and the second largest natural lake in the state of

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 ...

, after

Lake Chelan Lake Chelan ( ) is a narrow, long lake in Chelan County, north-central Washington state, U.S. Before 1927, it was the largest natural lake in the state by any measure. Upon the completion of Lake Chelan Dam in 1927, the elevation of the lake was ...

. It borders the cities of Seattle on the west,

Bellevue Bellevue means "beautiful view" in French. It may refer to: Placenames Australia * Bellevue, Western Australia * Bellevue Hill, New South Wales * Bellevue, Queensland * Bellevue, Glebe, an historic house in Sydney, New South Wales Canada ...

and Kirkland on the east, Renton on the south and Kenmore on the north, and encloses

Mercer Island Mercer Island is a city in King County, Washington, United States, located on an island of the same name in the southern portion of Lake Washington. Mercer Island is in the Seattle metropolitan area, with Seattle to its west and Bellevue to it ...

. The lake is fed by the

Sammamish River The Sammamish River (also known as Sammamish Slough) flows through north King County, Washington for about , draining Lake Sammamish into Lake Washington. Along its course, the Sammamish River flows through Redmond, Woodinville, Bothell, and K ...

at its north end and the Cedar River at its south. Lake Washington received its present name in 1854 after

Thomas Mercer Judge Thomas Mercer (March 11, 1813 – May 25, 1898) was a pioneer associated with the early history of Seattle. Biography Early life Mercer was born in Harrison County, Ohio on March 11, 1813, and was the eldest son of Aaron and Jane (Dicker ...

suggested it be named after

George Washington George Washington (February 22, 1732, 1799) was an American military officer, statesman, and Founding Father who served as the first president of the United States from 1789 to 1797. Appointed by the Continental Congress as commander of th ...

, as the new

Washington Territory The Territory of Washington was an organized incorporated territory of the United States that existed from March 2, 1853, until November 11, 1889, when the territory was admitted to the Union as the State of Washington. It was created from the ...

had been named the year before. Earlier names for the lake include the

Duwamish Duwamish may refer to: * Duwamish tribe, a Native American tribe in Washington state * Duwamish River, in Washington state * ''Duwamish'' (fireboat) See also * Elliott Bay Elliott Bay is a part of the Central Basin region of Puget Sound. It is ...

name ''Xacuabš'' (

Lushootseed Lushootseed (txʷəlšucid, dxʷləšúcid), also Puget Salish, Puget Sound Salish or Skagit-Nisqually, is a language made up of a dialect continuum of several Salish tribes of modern-day Washington state. Lushootseed is one of the Coast Salish ...

: literally "''xacu''" ''great-amount-of-water + "abš" people''), which referred to peoples who stayed along the coastline of Lake Washington, as well as Lake Geneva by Isaac N. Ebey; Lake Duwamish in railroad surveys under Governor

Isaac Stevens Isaac Ingalls Stevens (March 25, 1818 – September 1, 1862) was an American military officer and politician who served as governor of the Territory of Washington from 1853 to 1857, and later as its delegate to the United States House of Represen ...

; At-sar-kal in a map sketched by engineer

Abiel W. Tinkham Abiel is the given name of: * Abiel (biblical figure), two minor biblical figures * Abiel Abbot (1770–1828), American clergyman * Abiel Chandler (1777–1851), American merchant * Abiel Foster (1735–1806), American clergyman and politician *Abi ...

; and the Chinook Jargon name, "Hyas Chuck," or "It-Kow-Chug" 'big lake'.Historical Changes to Lake Washington and Route of the Lake Washington Ship Canal, King County, Washington
Michael Chrzastowski, United States Geological Survey, Department of the Interior The lake provides sport fishing opportunities. Some species found in this lake are Coastal Cutthroat Trout,

Rainbow Trout The rainbow trout (''Oncorhynchus mykiss'') is a species of trout native to cold-water tributaries of the Pacific Ocean in Asia and North America. The steelhead (sometimes called "steelhead trout") is an anadromous (sea-run) form of the coasta ...

Largemouth Bass The largemouth bass (''Micropterus salmoides'') is a carnivorous freshwater gamefish in the Centrarchidae ( sunfish) family, a species of black bass native to the eastern and central United States, southeastern Canada and northern Mexico, but ...

, Smallmouth Bass,

Yellow Perch The yellow perch (''Perca flavescens''), commonly referred to as perch, striped perch, American perch, American river perch or preacher is a freshwater perciform fish native to much of North America. The yellow perch was described in 1814 by Samu ...

, and

Black Crappie The black crappie (''Pomoxis nigromaculatus'') is a freshwater fish found in North America, one of the two types of crappies. It is very similar to the white crappie in size, shape, and habits, except that it is darker, with a pattern of black sp ...

Geography

ribbon lake A ribbon lake is a long and deep, finger-shaped lake, usually found in a glacial trough. As such, a ribbon lake is one of a number of glacial landscapes, including arêtes, corries, rock lips, rock basins and terminal moraines. Such a lake's ...

, Lake Washington is long, narrow and finger-like. Ribbon lakes are excavated by glaciers. As the Puget lobe of the Cordilleran Ice Sheet flowed south near the end of the

Late Pleistocene The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth division of ...

, it met bands of harder and softer rock. Erosion of the softer rock was faster and a linear depression was created in the flow direction. When the glacier melted, the lake filled with the meltwater, which was retained by

moraine A moraine is any accumulation of unconsolidated debris (regolith and rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a glacier or ice shee ...

deposits. A dam can also be created by the bands of harder rock either side of the softer rock. There is usually a river at both ends of a ribbon lake, one being the inlet, and the other, the outlet—though in the case of present-day Lake Washington, inlet rivers are located at both ends, with a man-made outlet in the middle. Two seaplane bases,

Kenmore Air Harbor Kenmore Air Harbor is a public-use seaplane base at the northern end of Lake Washington and south of the central business district of Kenmore, Washington, U.S. It primarily serves western Washington and parts of southwestern British Columbia. T ...

and Will Rogers – Wiley Post Memorial Seaplane Base, have air travel passenger terminals.

Creeks and rivers

The main inflowing rivers are the

Sammamish Sammamish ( ) is a city in King County, Washington, United States. The population was 67,455 at the 2020 census. Located on a plateau, the city is bordered by Lake Sammamish to the west and the Snoqualmie Valley to the east. Sammamish is a resid ...

and

Cedar Cedar may refer to: Trees and plants *''Cedrus'', common English name cedar, an Old-World genus of coniferous trees in the plant family Pinaceae *Cedar (plant), a list of trees and plants known as cedar Places United States * Cedar, Arizona * ...

Rivers, with the Cedar supplying most of the water. Seasonal changes in the flow of the Sammamish are moderated by a

weir A weir or low head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the river level. Weirs are also used to control the flow of water for outlets of l ...

at the Lake Sammamish inlet. The lake is drained by the

Lake Washington Ship Canal The Lake Washington Ship Canal, which runs through the city of Seattle, connects the fresh water body of Lake Washington with the salt water inland sea of Puget Sound. The Hiram M. Chittenden Locks accommodate the approximately difference in w ...

. In addition, there are numerous small creeks and rivers which feed the lake, including: * Coal Creek * Denny Creek ( O.O. Denny Park) * Fairweather Creek * Forbes Creek * Juanita Creek * Kelsey Creek * Little Creek * Lyon Creek * Mapes Creek * May Creek * McAleer Creek * Mercer Slough *

Ravenna Creek Ravenna Creek is a stream in the Ravenna, Seattle, Ravenna and Roosevelt, Seattle, Roosevelt neighborhoods of Seattle, Washington (state), Washington, whose present Daylighting (streams), daylighted length of nearly is entirely within the Ravenna ...

* Taylor Creek *

Thornton Creek Thornton Creek is of urban creeks and tributaries from southeast Shoreline through northeast Seattle to Lake Washington. Its watershed, the largest in Seattle, exhibits relatively dense biodiversity for an urban setting;Brokaw it is home to f ...

* Yarrow Creek * Yesler Creek Historically, construction of the Lake Washington Ship Canal drastically changed the inflow and outflow of the lake. Before construction of the canal in 1916, Lake Washington's outlet was the Black River, which joined the

Duwamish River {{authority control

Seattle metropolitan area