||This article needs additional citations for verification. (July 2008)|
Lake Union seen in 2012, against the backdrop of Seattle
|Location||Seattle, Washington, USA|
|Primary inflows||Lake Washington Ship Canal|
|Primary outflows||Lake Washington Ship Canal|
|Catchment area||571 square miles (1,480 km2)|
|Basin countries||United States|
|Surface area||580 acres (2.3 km2)|
|Average depth||34 feet (10 m)|
|Max. depth||50 feet (15 m)|
|Water volume||20,000 acre feet (25,000,000 m3)|
Lake Union received its present name from Thomas Mercer, who in 1854 correctly predicted that canals would someday join Lake Washington to Puget Sound in a "union of waters." The Duwamish called it "Small Lake" (Lushootseed: XáXu7cHoo, literally "small great-amount-of-water," the diminutive form of the word used for Lake Washington).
Three major streets are named in relation to the lake: Westlake Avenue, which runs along its western shore from Downtown to the Fremont Bridge; Eastlake Avenue, which runs along its eastern shore from Cascade to the University District, and Northlake Way, which runs along its northern shore from the University District past Gas Works Park to the edge of Fremont.
Boeing began production on Lake Union in 1916. Shipyards, wharves, and sawmills have also dotted the shore.
Lake Union's proximity to and scenic views of Seattle make it a popular recreational spot. Seaplanes operated by Kenmore Air and Seattle Seaplanes land and take off from the lake throughout the day. Pleasure boats from Lake Washington pass through on their way to Puget Sound. The Center for Wooden Boats holds a yearly wooden boat festival.
Gas Works Park is the largest park on Lake Union and the most popular for Seattleites and visitors. It is the venue for summer concerts and Seattle's major Fourth of July fireworks show. Other parks ring the lake, clockwise around the compass from Gas Works which is nearly due north: North Passage Point Park, South Passage Point Park, Fairview Park, Terry Pettus Park, and South Lake Union Park.
Floating homes 
Connections to other bodies of water 
Part of the Lake Washington Ship Canal system, water flows into the lake from Lake Washington through the Montlake Cut, and out via the Fremont Cut on its way to Puget Sound. Before construction of the canal, Lake Union emptied into Salmon Bay via a creek which followed roughly the same course as the Fremont Cut does today.
Because of the connection via the Hiram M. Chittenden Locks to the salt water of Puget Sound, there is some saline contamination, which increases in the summer as the inflow rate from Lake Washington decreases and the locks open more frequently for pleasure craft.
Competitive Rowing 
Lake Union is home to a several rowing centers, including Lake Union Crew, Lake Washington Rowing Club and Pocock Rowing Center, all members of USRowing. Also rowing out of bodies of water attached to Lake Union are the Seattle Rowing Center and the Conibear Shellhouse, serving the Washington Huskies.
Seaplane base 
Lake Union is home to two seaplane bases: Kenmore Air Harbor Seaplane Base (IATA: LKE, FAA LID: W55), and Seattle Seaplanes (IATA: LKE, FAA LID: 0W0), located one nautical mile (1.85 km) north of the central business district of Seattle.
- U.S. Geological Survey Geographic Names Information System: Lake Union
- "Lake Union". King County. Retrieved 15 November 2010.
- Phillips, James W. (1971). Washington State Place Names. University of Washington Press. p. 149. ISBN 0-295-95158-3.
- Thrush, Coll (2007). Native Seattle: Histories from the Crossing-Over Place. University of Washington Press. p. 223. ISBN 0-295-98700-6.
- PacificNorthwestMovies.com, Sleepless in Seattle
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