The Swinomish Channel is an long salt-water channel in

Washington state Washington (), officially the State of Washington, is a U.S. state, state in the Northwestern United States, Pacific Northwest region of the Western United States. Named for George Washington—the first President of the United States, U.S. p ...

, United States, which connects

Skagit Bay Skagit Bay is a bay and strait located in the U.S. state of Washington. It is part of the Whidbey Island Basin of Puget Sound. The Skagit River empties into Skagit Bay. To the south, Skagit Bay connects with the rest of Puget Sound via Saratoga ...

to the south, and Padilla Bay to the north, separating

Fidalgo Island Fidalgo Island is an island in Skagit County, Washington, located about north of Seattle. To the east, it is separated from the mainland by the Swinomish Channel, and from Whidbey Island to the south by Deception Pass. The island is named af ...

from mainland Skagit County. The Swinomish Channel is the smallest of the three entrances to

Puget Sound Puget Sound ( ) is a sound of the Pacific Northwest, an inlet of the Pacific Ocean, and part of the Salish Sea. It is located along the northwestern coast of the U.S. state of Washington. It is a complex estuarine system of interconnected m ...

—the other two being Deception Pass and

Admiralty Inlet Admiralty Inlet is a strait in the U.S. state of Washington connecting the eastern end of the Strait of Juan de Fuca to Puget Sound. It lies between Whidbey Island and the northeastern part of the Olympic Peninsula. Boundaries It is general ...

. The Swinomish Channel is partly natural and partly dredged. Before being dredged, it was a collection of shallow tidal sloughs,

salt marsh A salt marsh or saltmarsh, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. It is domin ...

es, and

mudflat Mudflats or mud flats, also known as tidal flats or, in Ireland, slob or slobs, are coastal wetlands that form in intertidal areas where sediments have been deposited by tides or rivers. A global analysis published in 2019 suggested that tidal f ...

s known as Swinomish Slough. The

United States Army Corps of Engineers , colors = , anniversaries = 16 June (Organization Day) , battles = , battles_label = Wars , website = , commander1 = ...

used dredging and diking to create a navigable channel, completed in 1937 during the

Great Depression The Great Depression (19291939) was an economic shock that impacted most countries across the world. It was a period of economic depression that became evident after a major fall in stock prices in the United States. The economic contagio ...

. The channel is heavily used by fishing boats, tugs, recreational craft, and shallow-draft freight vessels. To maintain navigable depths, the Swinomish Channel must be dredged at least every three years. Dedicated federal funding for continued dredging was eliminated in the 1990s. A study in 2004–2008 determined that sedimentation would render the channel's north end impassable for virtually all vessels by 2015, and its south end by 2019. The channel was dredged again in 2008. In 2012 the Army Corps of Engineers received funding from Congress for another dredging project, which was finished in January 2013. The channel was most recently dredged in 2018.

References

Channels of the United States Bodies of water of Skagit County, Washington Bodies of water of Washington (state) {{SkagitCountyWA-geo-stub