View source for Coastal engineering

{{Short description|Branch of civil engineering}}
[[File:Big_wave_cheney.JPG|thumb|right|[[wind wave|Wave]] attack on [[Ilfracombe]]'s [[sea wall]]s during a storm.]]
'''Coastal engineering''' is a branch of [[civil engineering]] concerned with the specific demands posed by constructing at or near the [[coast]], as well as the development of the coast itself.

The [[fluid dynamics|hydrodynamic]] impact of especially [[wind wave|waves]], [[tide]]s, [[storm surge]]s and [[tsunami]]s and (often) the harsh environment of salt [[seawater]] are typical challenges for the coastal engineer – as are the [[morphodynamics|morphodynamic]] changes of the coastal topography, caused both by the autonomous development of the system and human-made changes. The areas of interest in coastal engineering include the coasts of the [[ocean]]s, [[sea]]s, [[marginal sea]]s, [[estuary|estuaries]] and big lakes.

Besides the design, building and maintenance of '''coastal structures''', coastal engineers are often interdisciplinary involved in [[integrated coastal zone management]], also because of their specific knowledge of the hydro- and morphodynamics of the coastal system. This may include providing input and technology for e.g. [[environmental impact assessment]], [[port]] development, strategies for coastal defense, [[land reclamation]], offshore [[wind farm]]s and other energy-production facilities, etc.

==Specific challenges==
[[File:Sand suppletion on the Dutch coast 2.jpg|thumb|right|[[Beach nourishment]] at the [[Netherlands|Dutch]] coast.]]
The coastal environment produces challenges specific for this branch of engineering: waves, storm surges, tides, tsunamis, [[sea level]] changes, [[sea water]] and the [[marine ecosystem]].

Most often, in coastal engineering projects there is a need for [[metocean conditions]]: local wind and wave climate, as well as statistics for and information on other [[hydrodynamics|hydrodynamic quantities]] of interest. Also, [[bathymetry]] and [[beach morphodynamics|morphological changes]] are of direct interest. In case of studies of sediment transport and morphological changes, relevant properties of the sea bed sediments, water and ecosystem properties are needed.

===Long and short waves===
[[File:Munk ICCE 1950 Fig1.svg|thumb|right|Classification of the spectrum of ocean waves according to wave period, by [[Walter Munk]] (1950).<ref>{{citation | first=W.H. |last=Munk |author-link=Walter Munk |year=1950 |contribution=Origin and generation of waves |title=Proceedings 1st International Conference on Coastal Engineering |location=Long Beach, California |publisher=ASCE |pages= 1–4 |contribution-url=https://icce-ojs-tamu.tdl.org/icce/index.php/icce/article/view/904}}</ref>]] 
The occurrence of wave phenomena – like sea waves, swell, tides and tsunamis – require engineering knowledge of their physics, as well as models: both [[numerical model]]s and [[physical model]]s. The practices in present-day coastal engineering are more-and-more based on models [[verification and validation|verified and validated]] by experimental data.

Apart from the wave transformations themselves, for the waves coming from deep water into the shallow coastal waters and [[surf zone]], the effects of the waves are important. These effects include:
* the wave loading on coastal structures like [[breakwater (structure)|breakwater]]s, [[groyne]]s, [[jetty|jetties]], [[sea wall]]s and [[levee|dikes]]
* wave-induced currents, like the [[longshore current]] in the surf zone, [[rip current]]s and [[Stokes drift]], affecting sediment transport and morphodynamics
* wave agitation in harbors, which may result in harbor [[downtime]]
* wave overtopping over seawalls and dikes, which may e.g. threaten the stability of a dike

===Underwater construction===
{{main|Underwater construction}}
Coastal engineering takes place at or near the interface between land and water. Consequently a significant part of coastal engineering involves underwater construction, particularly for foundations. Breakwaters, sea walls, harbour structures like jetties, wharves and docks, bridges, tunnels, outfalls and causeways usually involve underwater work.

=== Sustainability and soft engineering ===
In recent decades, coastal engineers have favored non-structural solutions, which avoid adverse impacts that are typically cause by structures, such as sea walls, bulkheads, jetties, etc. These solutions include [[beach nourishment]], marsh restoration/creation, and habitat restoration. More recently, beneficial use of dredge material, which utilizes material dredged for navigation maintenance to nourish beaches and restore [[wetland]]s. Beneficial use is also employed to increase the elevation of marsh platforms in an attempt to adapt to sea level rise.

Regional sediment management has also become a focus strategy for coastal practitioners. This essentially uses nearshore sediment sources and knowledge of coastal morphology to identify which accretional features can be harvested to bolster erosional areas, understanding the harvested material will continue to accumulate. A common regional sediment management option is to dredge ebb and flood shoals to nourish beaches. 

Both beneficial use and regional sediment management recognizes the scarcity of material resources offshore and upland.

==See also==

{{div col}}
* {{annotated link|Beach#Erosion and accretion|Beach erosion and accretion}}
** {{annotated link|Beach evolution}}
*** {{annotated link|Beach evolution#Modern beach recession}}
** {{annotated link|Beach nourishment}}
** {{annotated link|Raised beach}}
* {{annotated link|Integrated coastal zone management}}
** {{annotated link|Coastal management}}, to prevent coastal erosion and creation of beach
** {{annotated link|Landforms#Coastal and oceanic landforms|Coastal and oceanic landforms}}
** {{annotated link|Coastal development hazards}}
** {{annotated link|Coastal erosion}}
** {{annotated link|Coastal geography}}
** Coastal engineering
*** {{annotated link|Hard engineering}}
*** {{annotated link|Soft engineering}}
** {{annotated link|Coastal morphodynamics}}
** {{annotated link|Coastal and Estuarine Research Federation}} (CERF)
** {{annotated link|Coast#Human impacts|Human impacts on coasts}}
** {{annotated link|Sea level rise}}
** {{annotated link|Natural hazard}}
* {{annotated link|Erosion}}
** {{annotated link|Bioerosion}}
** {{annotated link|Blowhole (geology)|Blowhole}}
** {{annotated link|Natural arch}}
** {{annotated link|Wave-cut platform}}
** {{annotated link|Hydrodynamic scour}}
*** {{annotated link|Bridge scour}}
*** {{annotated link|Tidal scour}}
** {{annotated link|Seabed gouging by ice}}
* {{annotated link|Longshore drift}}
** {{annotated link|Deposition (sediment)}}
** {{annotated link|Coastal sediment supply}}
** {{annotated link|Sand dune stabilization}}
** {{annotated link|Submersion (coastal management)|Submersion}}

{{div col end}}

==Notes==
{{Reflist}}

==References==
{{Refbegin}}
*{{citation
|  title=Coastal Processes with Engineering Applications
|  last1=Dean
|  first1=R.G.
|  last2=Dalrymple
|  first2=R.A.
|  isbn=9780521602754
|  year=2004
|  publisher=Cambridge University Press
| bibcode=2004cpea.book.....D
}}
*{{citation
|  title=Physical Models and Laboratory Techniques in Coastal Engineering
|  last=Hughes 
|  first=S.A.
|  isbn=9789810215415
|  series=Advanced series on ocean engineering
|  year=1993
|  publisher=World Scientific
}}
*{{citation
|  title=Introduction to Coastal Engineering and Management
|  last=Kamphuis 
|  first=J.W.
|  isbn=9789812834843
|  series=Advanced series on ocean engineering
|  year=2010
|  publisher=World Scientific
}}
*{{citation
|  title=History and Heritage of Coastal Engineering
|  last=Kraus
|  first=N.C.
|  isbn=9780784474143
|  year=1996
|  publisher=American Society of Civil Engineers
}}
*{{citation
|  title=Basic Coastal Engineering
|  last=Sorensen
|  first=R.
|  isbn=9781475726657
|  year=2013
|  publisher=Springer
}}
{{Refend}}

==External links==
{{Refbegin}}
*{{citation |url=http://www.coastal.udel.edu/coastal/ |title=The Coastal Engineering Page |publisher=University of Delaware |access-date=2018-09-13 | archive-url=https://web.archive.org/web/20171030213518/https://coastal.udel.edu/coastal/ | archive-date=2017-10-30 }}
*{{citation |url=http://journals.tdl.org/icce/index.php/icce/index|title=Coastal Engineering Proceedings |publisher=Texas Digital Library |access-date=2015-06-05 }} – Proceedings of the International Conference on Coastal Engineering (ICCE), held since 1950 (biannually since 1960).
{{Refend}}

{{coastal management|state=expanded}}
{{coastal geography}}
{{Construction overview}}
{{Authority control}}

[[Category:Coastal engineering| ]]
[[Category:Civil engineering]]
[[Category:Coastal construction]]