View source for Debouch

{{short description|Water runoff from a smaller place to a larger one}}
{{use mdy dates|date=March 2023}}
[[File:Iss016e019375.jpg|thumb|The port and city are the southern terminus of the [[Suez Canal]], which flows through Egypt and debouches into the [[Gulf of Suez]] near [[Port Tawfiq]]]]

In [[hydrology]], a '''debouch''' (or '''debouche''') is a place where [[surface runoff|runoff]] from a small, confined space [[discharge (hydrology)|discharges]] into a larger, broader [[body of water]]. The word is derived from the French verb ''déboucher'' ({{IPA|fr|debuʃe|lang}}), which means "to unblock, to clear". The term also has a military usage.<ref>{{Cite book |last=Ma |first=Yanxia |url=https://scholarworks.wm.edu/etd/1539616757/ |title=Continental Shelf Sediment Transport and Depositional Processes on an Energetic, Active Margin: the Waiapu River Shelf, New Zealand |work=Dissertations, Theses, and Masters Projects |date=2009 |pages=2, 19 |doi=10.25773/v5-8w3d-wz58}}</ref>

==Geology==
In fluvial geomorphology, a debouch is a place where runoff from a small, confined space emerges into a larger, broader space. Common examples are when a stream runs into a river or when a river runs into an ocean. Debouching can generate massive amounts of sediment transport. When a narrow stream travels down a mountain pass into a basin, an [[alluvial fan]] will form from the mass deposit of the sediment. The four largest rivers (the [[Amazon River|Amazon]], the [[Ganges]], the [[Yangtze]] and the [[Yellow River|Yellow]]) are responsible for 20% of the global discharge of sediment in to the oceans by debouches.<ref>{{Cite web |title=debouch as a noun |url=http://www.oed.com/view/Entry/47918?rskey=Lfbkiz&result=1&isAdvanced=false#eid |access-date=2012-10-10 |website=Oxford English Dictionary}}</ref>

==Geography==
In [[fluvial]] [[geography]], a debouch is a place where a body of water pours forth from a narrow opening. Some examples are: where a [[river]] or [[stream]] emerges from a narrow constraining [[landform]], such as a [[Defile (geography)|defile]], into open country or a wider space; a [[Creek (stream)|creek]] joins a [[river]]; or a stream flows into a lake.<ref>{{Cite magazine |last=Mitchell |first=Martha S. |date=May–June 2000 |title=River Rules: The Nature of Streams |url=http://www.forester.net/ec_0005_river.html |archive-url=https://web.archive.org/web/20050101180523/http://www.forester.net/ec_0005_river.html |archive-date=2005-01-01 |magazine=Erosion Control Magazine |url-status=usurped |page=5}}</ref>

==Military==
In [[military]] usage of debouch: as a noun, a [[fortification]] at the end of a [[defile (geography)|defile]] is sometimes known as a debouch; and as a verb, soldiers emerging from a narrow space and spreading out are also said to "debouch".<ref>{{Cite web |title=debouch as a verb |url=http://www.oed.com/view/Entry/47919#eid7298094 |access-date=2012-10-10 |website=Oxford English Dictionary}}</ref>

==See also==
*[[Fluvial landforms of streams]]
*[[Region of freshwater influence]]

==References==
{{reflist}}

==External links==
{{Sister project links 
<!-- Configuration parameters. Do not leave empty; populate, or remove -->
 |1= |collapsible= |display=Debouch |position= |style=

<!-- Specify "no" to exclude the corresponding project: -->
 |wikt= debouch|c= Debouch |commonscat= |n= no |q= no |s= no |author=no  |b=no |v=no

<!-- Specify "yes" to include the corresponding project: -->
 |voy= no |d= Q4156318|m=no  |mw= no |species= no |species_author=no 
}}
*{{Cite web |title=debouch |url=http://www.merriam-webster.com/dictionary/debouch |access-date=2012-10-10 |website=Merriam-Webster}}

{{Coastal geography}}

[[Category:Fluvial landforms]]
[[Category:Rivers]]
[[Category:Water streams]]
[[Category:Military terminology]]