Editing Breakwater (structure) (section)

==Unintended consequences==
Breakwaters are subject to damage and overtopping in severe storms. Some may also have the effect of creating unique types of  waves that attract surfers, such as [[The Wedge (surfing)|The Wedge]] at the Newport breakwater. 

=== Sediment effects ===
The dissipation of energy and relative calm water created in the lee of the breakwaters often encourage [[accretion (coastal management)|accretion]] of sediment (as per the design of the breakwater scheme). However, this can lead to excessive salient build up, resulting in [[tombolo]] formation, which reduces [[longshore drift]] shoreward of the breakwaters. This trapping of sediment can cause adverse effects down-drift of the breakwaters, leading to beach sediment starvation and increased [[coastal erosion]]. This may then lead to further engineering protection being needed down-drift of the breakwater development. Sediment accumulation in the areas surrounding breakwaters can cause flat areas with reduced depths, which changes the topographic landscape of the seabed.<ref name=":0">{{Cite journal|last1=Masucci|first1=Giovanni Diego|last2=Acierno|first2=Alessandro|last3=Reimer|first3=James Davis|date=2020|title=Eroding diversity away: Impacts of a tetrapod breakwater on a subtropical coral reef|url=https://onlinelibrary.wiley.com/doi/abs/10.1002/aqc.3249|journal=Aquatic Conservation: Marine and Freshwater Ecosystems|language=en|volume=30|issue=2|pages=290–302|doi=10.1002/aqc.3249|s2cid=212939487|issn=1052-7613|doi-access=free|url-access=subscription}}</ref>

Salient formations as a result of breakwaters are a function of the distance the breakwaters are built from the coast, the direction at which the wave hits the breakwater, and the angle at which the breakwater is built (relative to the coast). Of these three, the angle at which the breakwater is built is most important in the engineered formation of salients. The angle at which the breakwater is built determines the new direction of the waves (after they've hit the breakwaters), and in turn the direction that sediment will flow and accumulate over time.<ref>{{Cite journal|last1=Jackson|first1=Nancy L.|last2=Harley|first2=Mitchell D.|last3=Armaroli|first3=Clara|last4=Nordstrom|first4=Karl F.|date=2015-06-15|title=Beach morphologies induced by breakwaters with different orientations|journal=Geomorphology|volume=239|pages=48–57|doi=10.1016/j.geomorph.2015.03.010|bibcode=2015Geomo.239...48J}}</ref>

=== Environmental effects ===
The reduced heterogeneity in sea floor landscape introduced by breakwaters can lead to reduced [[species abundance]] and diversity in the surrounding ecosystems.<ref name=":1">{{Cite journal|last1=Aguilera|first1=Moisés A.|last2=Arias|first2=René M.|last3=Manzur|first3=Tatiana|date=2019|title=Mapping microhabitat thermal patterns in artificial breakwaters: Alteration of intertidal biodiversity by higher rock temperature|url= |journal=Ecology and Evolution|language=en|volume=9|issue=22|pages=12915–12927|doi=10.1002/ece3.5776|issn=2045-7758|pmc=6875675|pmid=31788225}}</ref> As a result of the reduced heterogeneity and decreased depths that breakwaters produce due to sediment build up, the UV exposure and temperature in surrounding waters increase, which may disrupt surrounding ecosystems.<ref name=":0" /><ref name=":1" /> 

[[Image:portland harbour hood entrance.JPG|thumb|right|Three of the four breakwaters forming [[Portland Harbour]], UK]]
[[Image:offelmer.jpg|thumb|The eight offshore breakwaters at Elmer, UK]]