View source for Canche

{{Short description|River in France}}
{{Infobox river
| name              = Canche
| image             = LaCancheMontreuil.jpg
| image_caption     = The Canche at Montreuil-sur-Mer
| map = Map of La Canche watershed.png
| map_caption = Watershed of the Canche River watershed
| pushpin_map       = France#France Hauts-de-France
| source1_location  = [[Pas-de-Calais]]
| mouth_location    = [[English Channel]]
| mouth_coordinates = {{coord|50|32|27|N|1|35|56|E|format=dms|display=inline,title}}
| subdivision_type1 = Country
| subdivision_name1 = [[France]]
| length            = {{convert|100|km|mi|abbr=on}}
| source1_elevation =
| discharge1_avg    = {{convert|15.1|m3/s|cuft/s|abbr=on}}
| basin_size        = {{convert|1274|km2|mi2|abbr=on}}
}}
The [[river]] '''Canche''' ({{IPA|fr|kɑ̃ʃ}}; {{langx|nl|Kwinte}}) is one of the rivers that flow from the plateau of southern [[Boulonnais (land area)|Boulonnais]] and [[Picardy]], into the [[English Channel]], of which the [[Somme (river)|Somme]] is the largest example. It is {{convert|100.2|km|mi|abbr=on}} long.<ref name=sandre>{{sandre|id=E54-003-|nom=La Canche}}</ref> The [[catchment basin|basin]] of the Canche extends to {{convert|1274|km2|mi2}} and lies in the south of the [[Departements of France|département]] of [[Pas-de-Calais]]. Forming an [[alluvial valley]] from {{convert|1|to|2|km|mi|1}} wide, the Canche valley also contains [[marsh]]es, [[meadows]] and small [[Woodland|woods]]. The gentle gradient, averaging 1.5&nbsp;percent, gives the river a [[meander]]ing course.
The river rises at [[Gouy-en-Ternois]] and passes [[Frévent]], [[Hesdin]], and [[Montreuil-sur-Mer]] before leaving the chalk to flow to the coast between [[Étaples]] and [[Le Touquet-Paris-Plage]]. Its principal tributaries are the [[Ternoise]], the [[Planquette]], the [[Créquoise]], the [[Bras de Bronne]], the Course, the Dordogne (not to be confused with the [[Dordogne]]) and the [[Huitrepin]] which all join on its right bank, i.e. to the north of the Canche. The lie of the land means there is no notable [[tributary]] from the south until the [[Grande Tringue]], which flows from marshland into the small, dredged [[estuary]].
==History==
The valley of the Canche has been occupied by man since ancient times because of the productive nature of the land. The unhealthy aspect of marshland means much has been done over the centuries to drain the land efficiently, which has brought about the partial destruction of its original character. The principal activities of the village communities occupying the valley and its surrounds have been (and still are) farming, fishing and [[Reed bed|reed]] harvesting.<ref name="humide">Helga Scarwell et Magalie Franchomme, ''Autour des zones humides : espaces productifs d'hier et conflits d'aujourd'hui'', La revue en sciences de l'environnement: Vertigo, 1 mai 2005. [http://www.vertigo.uqam.ca/vol6no1/art11vol6no1/h_scarwell_m_franchomme.html Read online]</ref>
The extraction of [[peat]] from the marshes of the lower river was known in the 16th century; peat being the principal means of heating and also a multi-purpose fertilizer.<ref name="humide" />  The [[alder]] tree, which grew well in the local marshy soils, contributed to bind the ground, and produced timber. It was realized that [[forestry]] also helped in [[drainage]]. Further developments in the 18th century saw permanent enclosures with animals being fenced-in and property boundaries being created by the planting of hedges and the digging of ditches, contributing to organized and cooperative farming methods.
The 18th century also saw the emergence of new perceptions of marshland, long considered as unhealthy places in which to live.{{Citation needed|date=July 2019}}  Administrative authorities encouraged action to recover the peat marshes by drainage work and the planting of more trees. The reduction of marshland again allowed for even more areas of cultivation to feed the increasing population.
During the 19th century, technical progress (for example, the replacement of [[windmill]]s by [[steam engines]]) led to further improvements in drainage, contributing to the drying-up of the valley downstream as far as [[Hesdin]]. In the last quarter of the 20th century the authorities became aware of the importance of the marshes and started trying to preserve them, having earlier contributed to their disappearance. The Canche and its valley have been incorporated into a national natural reserve since 1987.<ref name="conservatoire">[http://www.conservatoire-du-littoral.fr/front/process/Content.asp?rub=8&rubec=208&site=1690&entite=208 The estuary of the Canche] {{Webarchive|url=https://web.archive.org/web/20071018005404/http://www.conservatoire-du-littoral.fr/front/process/Content.asp?rub=8&rubec=208&site=1690&entite=208# |date=2007-10-18 }}</ref>
==Environmental issues==
[[File:Mouth of the River Canche.JPG|thumb|The estuary of the Canche]]
The Canche [[estuary]] was the first site in northern France where a conservation victory, in respect of the coast, was first achieved, in 1976.{{Vague|date=July 2019}}
Plans had been made to put in place an earlier project, dating from the 1960s, to create an artificial environment on the estuary. The work included creating a harbour and a marina. This was supposed to be “compensation” for extracting the waters of the Canche at Hesdin in order to supply the city of [[Lille]]. Of course, this threatened to destroy the rich wildlife and flora of the estuary. The mobilisation of the local inhabitants, various associations and many scientists, after many public enquiries and heated arguments, stopped the plans and left the estuary to nature.<ref>[http://www.nord-nature.org/la_federation/30ah/histoire_grands_combats.htm The barrage project] on the Fédération Nord-Nature website.</ref>
==Flora and fauna==
With [[sandbars]] and [[Spit (landform)|spits]], the estuary of the Canche is typical of the estuaries of this region of France. The coastal dunes, marshes and valley are home to 485 different plants and a diverse range of wildlife. Seventy-five varieties of resident and migratory birds nest in and around the estuary and valley, such as the [[European nightjar|nightjar]], [[woodlark]], several types of [[warbler]]s, [[common snipe]], [[Eurasian oystercatcher|oystercatchers]] (using rabbit-holes as homes) and the predatory [[Merlin (bird)|merlin]] and [[common buzzard]].
This area shelters mammals such as [[deer]], [[wild boar]], [[red fox]]es, [[European badger]]s, [[stoat]]s, [[squirrel]]s, [[European rabbits]] and the occasional seal, but, in contrast to the bay of the [[Somme (river)|Somme]], the estuary of the Canche does not seem to possess a seal colony.
Numerous [[amphibian]]s ([[Common toad]]s, [[newt]]s and [[frog]]s) are found in and along the river.<ref name="conservatoire" />
==Gallery==
<gallery class="center">
Image:frevent01.jpg|The millrace of the Moulin Blonde at Frévent, south of St. Pol
Image:Etaples-port.JPG|Étaples - The Canche estuary
Image:Common.shelduck.2.arp.750pix.jpg|[[Common shelduck]] on the estuary
File:Bassin de la Canche.svg|Map of Canche Bassin
</gallery>
==See also==
*[[Schéma directeur d'aménagement et de gestion des eaux|French water management scheme]]
==References==
{{Reflist}}
*''Carte Géologique de la France à l'échelle du millionième'' 6th edn. BRGM (2003) {{ISBN|2-7159-2158-6}}
==External links==
*[http://www.gesteau.eaufrance.fr/sage/bassin.php?bassin=AP Site de l'Agence de l'eau Bassin Artois-Picardie] {{in lang|fr}}
*[http://perso.wanadoo.fr/sagedelacanche Site personnel SAGE de la Canche] {{in lang|fr}}
*[http://www.nordmag.fr/nord_pas_de_calais/canche_authie/canche_authie.htm Tourisme dans la vallée de la Canche] {{Webarchive|url=https://web.archive.org/web/20210418185149/http://www.nordmag.fr/nord_pas_de_calais/canche_authie/canche_authie.htm |date=2021-04-18 }} {{in lang|fr}}
{{commons}}
{{Authority control}}
[[Category:Rivers of France]]
[[Category:Rivers of the Pas-de-Calais]]
[[Category:Rivers of Hauts-de-France]]
[[Category:Coastal basins of the English Channel in France|0Canche]]