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27-456: Rosario Strait is a strait in northern Washington state , separating San Juan County and Skagit and Whatcom Counties . It extends from the Strait of Juan de Fuca about 23 kilometres (14 mi) north to the Strait of Georgia . The USGS defines its southern boundary as a line extending from Point Colville on Lopez Island to Rosario Head on Fidalgo Island , and its northern boundary as

54-579: A channel is a landform on which a relatively narrow body of water is situated, such as a river , river delta or strait . While channel typically refers to a natural formation, the cognate term canal denotes a similar artificial structure. Channels are important for the functionality of ports and other bodies of water used for navigability for shipping . Naturally, channels will change their depth and capacity due to erosion and deposition processes. Humans maintain navigable channels by dredging and other engineering processes. By extension,

81-487: A constant flux. Channel heads associated with hollows in steep terrain frequently migrate up and down hillslopes depending on sediment supply and precipitation. Natural channels are formed by fluvial process and are found across the Earth . These are mostly formed by flowing water from the hydrological cycle , though can also be formed by other fluids such as flowing lava can form lava channels . Channels also describe

108-465: A line from Point Migley on Lummi Island to the east tip of Puffin Island (just east of Matia Island ) and then to Point Thompson on Orcas Island . Rosario Strait runs north-south between Lopez , Decatur , Blakely , and Orcas Islands on the west, and Fidalgo , Cypress, Sinclair , and Lummi Islands on the east. Rosario Strait is a major shipping channel. More than 500 oil tankers pass through

135-677: A name for Rosario Strait. In 1847 Charles Wilkes , during the Wilkes Expedition , gave Rosario Strait the name Ringgold Channel after one of his officers. Then in 1847 the British Captain Henry Kellett reorganized the British Admiralty charts, in the process removing the "pro-American" names given by Wilkes and affirming pro-British names and Spanish names. He affirmed the name Gulf of Georgia (Strait of Georgia) given by George Vancouver and used

162-632: A shortened version of Eliza's name for the Strait of Georgia to replace both Wilkes' and Eliza's original names for Rosario Strait. Following the Oregon Treaty it was assumed by the British to be the route of the deepest channel to the open sea from the 49th Parallel boundary's terminus in the middle of the Georgia Strait , and is in fact the shortest shipping route. Haro Strait , west of

189-420: Is a difference between low gradient streams (less than a couple of percent in gradient or slightly sloped) and high gradient streams (steeply sloped). A wide variety of stream channel types can be distinguished (e.g. braided rivers , wandering rivers, single-thread sinuous rivers etc.). During floods , water flow may exceed the capacity of the channel and flood waters will spill out of the channel and across

216-462: Is frequently called a canal , with the Panama Canal providing an example. The term not only includes the deep-dredged   ship-navigable parts of an estuary or river leading to port facilities, but also to lesser channels accessing boat port-facilities such as marinas . When dredged channels traverse bay mud or sandy bottoms, repeated dredging is often necessary because of

243-661: Is the most upslope part of a channel network and is defined by flowing water between defined identifiable banks. A channel head forms as overland flow and/or subsurface flow accumulate to a point where shear stress can overcome erosion resistance of the ground surface. Channel heads are often associated with colluvium , hollows and landslides . Overland flow is a primary factor in channel initiation where saturation overland flow deepens to increase shear stress and begin channel incision. Overland flows converge in topographical depressions where channel initiation begins. Soil composition, vegetation, precipitation, and topography dictate

270-401: Is typically reserved for much larger, wider features of the marine environment. There are exceptions, with straits being called canals; Pearse Canal , for example. Straits are the converse of isthmuses . That is, while a strait lies between two land masses and connects two large areas of ocean, an isthmus lies between two areas of ocean and connects two large land masses. Some straits have

297-642: The San Juan Islands , which is wider though somewhat longer, was the American preference for the boundary and its eventual location following the arbitration of the dispute over the San Juan Islands, known as the Pig War . Strait A strait is a water body connecting two seas or two water basins. While the landform generally constricts the flow, the surface water still flows, for

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324-468: The Suez Canal . Although rivers and canals often provide passage between two large lakes, and these seem to suit the formal definition of strait, they are not usually referred to as such. Rivers and often canals, generally have a directional flow tied to changes in elevation, whereas straits often are free flowing in either direction or switch direction, maintaining the same elevation. The term strait

351-586: The valley bottom, floodplain or drainage area . Examples of rivers that are trapped in their channels: Grand Canyon and Black Canyon of the Gunnison . In a larger nautical context, as a geographical place name, the term channel is another word for strait , which is defined as a relatively narrow body of water that connects two larger bodies of water. In this nautical context, the terms strait , channel , sound , and passage are synonymous and usually interchangeable. For example, in an archipelago ,

378-545: The amount and rate of overland flow. The composition of a soil determines how quickly saturation occurs and cohesive strength retards the entrainment of material from overland flows. Vegetation slows infiltration rates during precipitation events and plant roots anchor soil on hillslopes. Subsurface flow destabilizes soil and resurfaces on hillslopes where channel heads are often formed. This often results in abrupt channel heads and landslides. Hollows form due to concentrated subsurface flows where concentrations of colluvium are in

405-567: The deeper course through a reef , sand bar , bay , or any shallow body of water. An example of a river running through a sand bar is the Columbia Bar —the mouth of the Columbia River . A stream channel is the physical confine of a stream ( river ) consisting of a bed and stream banks . Stream channels exist in a variety of geometries. Stream channel development is controlled by both water and sediment movement. There

432-505: The most part, at the same elevation on both sides and through the strait in both directions. In some straits there may be a dominant directional current through the strait. Most commonly, it is a narrowing channel that lies between two land masses . Some straits are not navigable, for example because they are either too narrow or too shallow, or because of an unnavigable reef or archipelago . Straits are also known to be loci for sediment accumulation. Usually, sand-size deposits occur on both

459-480: The name Boca de Fidalgo, in honor of Salvador Fidalgo , to Rosario Strait, which was thought to be a bay. In 1791 José María Narváez renamed it Canal de Fidalgo after determining it was a strait. Also in 1791 Francisco de Eliza gave the name Gran Canal de Nuestra Señora del Rosario la Marinera to what is now the Strait of Georgia . In 1792, George Vancouver explored the region and gave the Strait of Georgia its present name after King George III . He did not provide

486-472: The potential to generate significant tidal power using tidal stream turbines . Tides are more predictable than wave power or wind power . The Pentland Firth (a strait) may be capable of generating 10  GW . Cook Strait in New Zealand may be capable of generating 5.6 GW even though the total energy available in the flow is 15 GW. Straits used for international navigation through

513-400: The product of the sediment load and bed Bukhara size is proportional to the product of discharge and channel slope. A term " navigable channel " is used as a nautical term to mean a lane for ship travel, frequently marked (cf. Buoy ) and sometimes dredged . Thoresen distinguishes few categories of channels, from A (suitable for day and night navigation with guaranteed fairway depth ) all

540-615: The strait each year, to and from the Cherry Point Refinery and refineries near Anacortes. The strait is in constant use by vessels bound for Cherry Point, Bellingham , Anacortes, and the San Juan Islands. Vessels bound for British Columbia or Alaska also frequently use it in preference to the passages farther west, when greater advantage can be taken of the tidal currents. In 1790 the Spanish explorers Manuel Quimper and Juan Carrasco , sailing aboard Princesa Real , gave

567-430: The term also applies to fluids other than water, e.g., lava channels . The term is also traditionally used to describe the waterless surface features on Venus . Channel initiation refers to the site on a mountain slope where water begins to flow between identifiable banks. This site is referred to as the channel head and it marks an important boundary between hillslope processes and fluvial processes. The channel head

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594-423: The territorial sea between one part of the high seas or an exclusive economic zone and another part of the high seas or an exclusive economic zone are subject to the legal regime of transit passage ( Strait of Gibraltar , Dover Strait , Strait of Hormuz ). The regime of innocent passage applies in straits used for international navigation (1) that connect a part of high seas or an exclusive economic zone with

621-639: The territorial sea of a coastal nation ( Straits of Tiran , Strait of Juan de Fuca , Strait of Baltiysk ) and (2) in straits formed by an island of a state bordering the strait and its mainland if there exists seaward of the island a route through the high seas or through an exclusive economic zone of similar convenience with respect to navigational and hydrographical characteristics ( Strait of Messina , Pentland Firth ). There may be no suspension of innocent passage through such straits. [REDACTED] Media related to Straits at Wikimedia Commons Channel (geography) In physical geography and hydrology ,

648-574: The two opposite strait exits, forming subaqueous fans or deltas . The terms channel , pass , or passage can be synonymous and used interchangeably with strait , although each is sometimes differentiated with varying senses. In Scotland, firth or Kyle are also sometimes used as synonyms for strait. Many straits are economically important. Straits can be important shipping routes and wars have been fought for control of them. Numerous artificial channels, called canals , have been constructed to connect two oceans or seas over land, such as

675-688: The unstable subsequent movement of benthic soils. Responsibility for monitoring navigability conditions of navigation channels to various port facilities varies, and the actual maintenance work is frequently performed by a third party. Storms, sea-states, flooding, and seasonal sedimentation adversely affect navigability . In the U.S., navigation channels are monitored and maintained by the United States Army Corps of Engineers (USACE), although dredging operations are often carried out by private contractors (under USACE supervision). USACE also monitors water quality and some remediation. This

702-512: The water between islands is typically called a channel or passage . The English Channel is the strait between England and France. The channel form is described in terms of geometry (plan, cross-sections, profile) enclosed by the materials of its bed and banks. This form is under influence of two major forces: water discharge and sediment supply. For erodible channels the mutual dependence of its parameters may be qualitatively described by Lane's Principle (also known as Lane's relationship ):

729-400: The way to D with no navigational aids and only estimated depths provided to the shipmaster . With regard to the dredging , channels can be unrestricted (wide enough to accommodate 10-15 widths of a largest ship used in this channel, semi-restricted with limited dredging in shallow waters, and fully restricted , where the entire channel is dredged. The latter, entirely human-made, channel

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