Wikipedia:
Transportation
Rail
Road
Ports and canals
Canals (active)
Constructed canals only[b]
Lake Washington Ship Canal / Chittenden Locks (Ballard locks), Seattle
Canals (abandoned)
Cascade Locks and Canal, Columbia River
Celilo Canal, Columbia River
Ports
Water management
Flood control
McNary Levee System, Columbia River (Tri-Cities)
Volcanic
Volcano-related infrastructure around Mount St. Helens related to its 1980 eruption and future eruptions
Flumes and siphons
Irrigation
Center pivot irrigation in the Columbia Basin makes mile-wide circles around Potholes Reservoir, visible from space.
See also: List of United States Bureau of Reclamation dams
Columbia Basin Project, largest reclamation project in United States
Banks Lake, a 27-mile (43 km) long reservoir
Potholes Reservoir: 670,000 irrigated acres
Conconully Dam and Reservoir
Yakima Project, 464,000 irrigable acres[8]
Municipal water supply
Further information: Chehalis Gap § Water
Casad Dam (Bremerton watershed)
McAllister Wellfield (Olympia)
Culmback Dam / Spada Reservoir (Sultan River - City of Everett)
Cedar River (Washington) § River modifications and management – watershed
Chester Morse Lake and masonry dam
Tolt pipeline (Cascades to Seattle)
Howard A. Hanson Dam and reservoir
Wastewater
Brightwater sewage treatment plant (Bothell)
South Treatment Plant (Renton)
By type:
Bridges
Many bridges are visible in this photograph of the northern Puget Sound area of Washington, including the four floating bridges listed
Floating bridges
Washington has more floating bridges than any other state,[9] and the world's three longest ones, including:
Evergreen Point Floating Bridge (2016) (SR 520 or "Evergreen Point"), replaced the 1963 Evergreen Point Floating Bridge, and is world's longest
Lacey V. Murrow Memorial Bridge (I-90), second longest in world
Hood Canal Bridge, world's third longest floating bridge overall, and the longest floating bridge on tidal saltwater
Homer M. Hadley Memorial Bridge (I-90), fifth longest in world
Historically notable bridges and incidents
Chow Chow Bridge one of the first cable-stayed bridge designs in the United States, and the first in Washington
Hood Canal Bridge partially sank during storm
Tacoma Narrows Bridge (1940), "Galloping Gertie", collapsed during windstorm four months after opening
Lacey V. Murrow Memorial Bridge, sank during storm
Dams
Pipelines
McChord Pipeline (jet fuel)
Northwest Pipeline (natural gas)
Olympic pipeline (Olympic pipeline explosion) (petroleum)
Tolt pipeline (water)
Tunnels
Highways
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