{"id":138,"date":"2016-11-29T16:49:44","date_gmt":"2016-11-29T15:49:44","guid":{"rendered":"https:\/\/www.ern.org\/fr\/?page_id=138"},"modified":"2026-02-06T07:43:54","modified_gmt":"2026-02-06T07:43:54","slug":"effacement-du-barrage-de-kernansquillec","status":"publish","type":"page","link":"https:\/\/www.ern.org\/fr\/effacement-du-barrage-de-kernansquillec\/","title":{"rendered":"Effacement du barrage de Kernansquillec"},"content":{"rendered":"\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-2erpt6-fe9139f1e8857a910cc36a621953c656\">\n.flex_column.av-2erpt6-fe9139f1e8857a910cc36a621953c656{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-2erpt6-fe9139f1e8857a910cc36a621953c656 av_one_full  avia-builder-el-0  el_before_av_one_half  avia-builder-el-first  first flex_column_div av-zero-column-padding  '     ><style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-2amu8q-d0ecee08fbca984c1f1ced845c2a4c09\">\n#top .av-special-heading.av-2amu8q-d0ecee08fbca984c1f1ced845c2a4c09{\npadding-bottom:10px;\n}\nbody .av-special-heading.av-2amu8q-d0ecee08fbca984c1f1ced845c2a4c09 .av-special-heading-tag .heading-char{\nfont-size:25px;\n}\n.av-special-heading.av-2amu8q-d0ecee08fbca984c1f1ced845c2a4c09 .av-subheading{\nfont-size:15px;\n}\n<\/style>\n<div  class='av-special-heading av-2amu8q-d0ecee08fbca984c1f1ced845c2a4c09 av-special-heading-h2 blockquote modern-quote  avia-builder-el-1  avia-builder-el-no-sibling '><h2 class='av-special-heading-tag '  itemprop=\"headline\"  >Effacement du barrage de Kernansquillec<\/h2><div class='av-subheading av-subheading_below'><p>Le L\u00e9guer (Fleuve c\u00f4tier), C\u00f4tes d&rsquo;Armor, France, 1996<\/p>\n<\/div><div class=\"special-heading-border\"><div class=\"special-heading-inner-border\"><\/div><\/div><\/div><\/div>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-242op6-157e727625445298a9aff519a920522b\">\n.flex_column.av-242op6-157e727625445298a9aff519a920522b{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-242op6-157e727625445298a9aff519a920522b av_one_half  avia-builder-el-2  el_after_av_one_full  el_before_av_one_half  first flex_column_div av-zero-column-padding  column-top-margin'     ><section  class='av_textblock_section av-1u7q5e-86e045b7ae40e2bcaa19432d64ba5999 '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><h3>Contexte<\/h3>\n<p>Ce barrage d&rsquo;environ 15 m de haut sur le L\u00e9guer, en b\u00e9ton \u00e0 vo\u00fbtes multiples construit vers 1920, sous le r\u00e9gime de la concession, alimentait une papeterie en \u00e9lectricit\u00e9. La retenue (400 000 m3), situ\u00e9e \u00e0 l&rsquo;aval de zones agricoles, souffrait d&rsquo;une forte eutrophisation des eaux et d&rsquo;un envasement tr\u00e8s important de l&rsquo;ordre de 50%. La derni\u00e8re vidange de la retenue effectu\u00e9e lors de la visite d\u00e9cennale, r\u00e9alis\u00e9e en France tous les dix ans sauf d\u00e9rogation, s&rsquo;\u00e9tait r\u00e9v\u00e9l\u00e9e catastrophique pour la faune aquatique, ensevelie sous la vase. Lors de l&rsquo;instruction de l&rsquo;autorisation devant succ\u00e9der \u00e0 la concession, l&rsquo;administration a indiqu\u00e9 au concessionnaire sortant les conditions de l&rsquo;octroi du nouveau titre : notamment augmentation de la capacit\u00e9 des ouvrages \u00e9vacuateurs de crue, d\u00e9senvasement de la retenue. L&rsquo;ancien concessionnaire a pr\u00e9f\u00e9r\u00e9 renoncer \u00e0 sa demande : les ouvrages ont \u00e9t\u00e9 remis \u00e0 l&rsquo;Etat \u00e0 la fin de la concession le 31 d\u00e9cembre 1993.<\/p>\n<p>Lors des crues de janvier 1995, sept maisons avaient d\u00fb \u00eatre \u00e9vacu\u00e9es en aval sur la recommandation des experts, en raison de l&rsquo;insuffisance des ouvrages \u00e9vacuateurs de crues, l&rsquo;eau \u00e9tant pr\u00eate \u00e0 d\u00e9verser par dessus le barrage. En outre, il fermait la rivi\u00e8re du L\u00e9guer \u00e0 la circulation des saumons et autres poissons migrateurs. Compte tenu de son int\u00e9r\u00eat \u00e9nerg\u00e9tique limit\u00e9, de sa v\u00e9tust\u00e9 et des risques pour la s\u00e9curit\u00e9 publique et l&rsquo;environnement, l&rsquo;Etat a d\u00e9cid\u00e9 de d\u00e9molir l&rsquo;ouvrage.<\/p>\n<\/div><\/section><br \/>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-1rqhyi-59ac60708ed89895a330edeb74ddfa21\">\n#top .hr.hr-invisible.av-1rqhyi-59ac60708ed89895a330edeb74ddfa21{\nheight:50px;\n}\n<\/style>\n<div  class='hr av-1rqhyi-59ac60708ed89895a330edeb74ddfa21 hr-invisible  avia-builder-el-4  el_after_av_textblock  el_before_av_textblock '><span class='hr-inner '><span class=\"hr-inner-style\"><\/span><\/span><\/div><br \/>\n<section  class='av_textblock_section av-5xcnu-782911db2b47d5fbe1fc24f331ec3633 '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><h3>Ma\u00eetrise d&rsquo;ouvrage<\/h3>\n<p>La ma\u00eetrise d&rsquo;ouvrage a \u00e9t\u00e9 assur\u00e9e par l&rsquo;Etat (minist\u00e8re de l&rsquo;Industrie). Le co\u00fbt de 0,9 Million \u20ac (6,1 millions de francs) a \u00e9t\u00e9 support\u00e9 par l&rsquo;Etat avec une aide de l&rsquo;agence de l&rsquo;eau.<\/p>\n<\/div><\/section><br \/>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-1g371u-5fdad1bbceab6efe85841780952c2bfe\">\n#top .hr.hr-invisible.av-1g371u-5fdad1bbceab6efe85841780952c2bfe{\nheight:50px;\n}\n<\/style>\n<div  class='hr av-1g371u-5fdad1bbceab6efe85841780952c2bfe hr-invisible  avia-builder-el-6  el_after_av_textblock  el_before_av_textblock '><span class='hr-inner '><span class=\"hr-inner-style\"><\/span><\/span><\/div><br \/>\n<section  class='av_textblock_section av-1ad5m2-a1fa6d493ce9ac7804c1202df6225325 '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><h3>Difficult\u00e9s particuli\u00e8res<\/h3>\n<p>Les principales difficult\u00e9s ont concern\u00e9 la vidange et les pr\u00e9cautions \u00e0 prendre en raison du fort envasement de la retenue et de la pr\u00e9sence d&rsquo;une pisciculture et de captages d&rsquo;eau potable \u00e0 l&rsquo;aval. La vidange du barrage, autoris\u00e9e par un arr\u00eat\u00e9 pr\u00e9fectoral du 12 avril 1996, a \u00e9t\u00e9 pr\u00e9c\u00e9d\u00e9e d&rsquo;un hydrocurage, sur l&rsquo;axe du lit mineur, de 95 000 m3 de boues, avec traitement dans des lagunes de d\u00e9cantation afin de prot\u00e9ger la rivi\u00e8re en aval. Elle s&rsquo;est termin\u00e9e sans atteinte notable \u00e0 la qualit\u00e9 des eaux gr\u00e2ce aux pr\u00e9cautions prises.<\/p>\n<p>Le permis de d\u00e9molir a \u00e9t\u00e9 accord\u00e9 par le pr\u00e9fet le 17 septembre 1996. Les travaux de d\u00e9molition du barrage ont \u00e9t\u00e9 achev\u00e9s en 1996 sans difficult\u00e9 particuli\u00e8re. Une op\u00e9ration de r\u00e9habilitation et de mise en valeur de l&rsquo;ensemble de la vall\u00e9e, y compris une friche industrielle proche du barrage, va \u00eatre engag\u00e9e maintenant par l&rsquo;association de sauvegarde du L\u00e9guer.<\/p>\n<\/div><\/section><br \/>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-12i30y-0842f7aaa8054cb5c1fb6e4c519c6aba\">\n#top .hr.hr-invisible.av-12i30y-0842f7aaa8054cb5c1fb6e4c519c6aba{\nheight:50px;\n}\n<\/style>\n<div  class='hr av-12i30y-0842f7aaa8054cb5c1fb6e4c519c6aba hr-invisible  avia-builder-el-8  el_after_av_textblock  el_before_av_textblock '><span class='hr-inner '><span class=\"hr-inner-style\"><\/span><\/span><\/div><br \/>\n<section  class='av_textblock_section av-lsddn163-7a661119c4b9a681bfcca446d5b1d42f '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><h3>En savoir +<\/h3>\n<ul>\n<li><a href=\"https:\/\/ern-sosloirevivante.org\/wp-content\/uploads\/2024\/02\/21_12_rex_r1_leguer_vbat.pdf\" target=\"_blank\" rel=\"noopener\">Fiche \u00ab\u00a0retour d&rsquo;exp\u00e9rience\u00a0\u00bb &#8211; OFB, 2010<\/a><\/li>\n<li><a href=\"http:\/\/www.riviere-du-leguer.com\/leguer\/papeteries.htm\" target=\"_blank\" rel=\"noopener\">association Vall\u00e9e du L\u00e9guer<\/a><\/li>\n<\/ul>\n<\/div><\/section><\/p><\/div>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-yum02-1eb7d220616c5b6a9593d4c8ed81f28d\">\n.flex_column.av-yum02-1eb7d220616c5b6a9593d4c8ed81f28d{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-yum02-1eb7d220616c5b6a9593d4c8ed81f28d av_one_half  avia-builder-el-10  el_after_av_one_half  el_before_av_one_half  flex_column_div av-zero-column-padding  column-top-margin'     ><style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-p0doq-77a2d479e00e57563c8931772512388e\">\n#top .avia-gallery.av-p0doq-77a2d479e00e57563c8931772512388e .avia-gallery-thumb a{\nwidth:100%;\n}\n<\/style>\n<div  class='avia-gallery av-p0doq-77a2d479e00e57563c8931772512388e avia_animate_when_visible  avia-builder-el-11  avia-builder-el-no-sibling  deactivate_avia_lazyload avia-gallery-animate avia-gallery-1'  itemprop=\"image\" itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\" ><meta itemprop=\"contentURL\" content=\"https:\/\/www.ern.org\/fr\/effacement-du-barrage-de-kernansquillec\/\"><div class='avia-gallery-thumb'><a href=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam-1.jpg\" data-srcset=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam-1.jpg 448w, https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam-1-300x223.jpg 300w\" data-sizes=\"(max-width: 448px) 100vw, 448px\" data-rel='gallery-1' data-prev-img='https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam-1.jpg' class='first_thumb lightbox ' data-onclick='1' title='Kernansquillec dam  and its reservoir \u00a9 Postal card'  itemprop=\"thumbnailUrl\"  ><img decoding=\"async\" fetchpriority=\"high\" class=\"wp-image-216 avia-img-lazy-loading-not-216\"  data-avia-tooltip='Kernansquillec dam  and its reservoir \u00a9 Postal card' src=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam-1.jpg\" width=\"448\" height=\"333\"  title='kernansquillec_dam' alt='' srcset=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam-1.jpg 448w, https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam-1-300x223.jpg 300w\" sizes=\"(max-width: 448px) 100vw, 448px\" \/><div class='big-prev-fake'><img decoding=\"async\" loading=\"lazy\" class=\"wp-image-216 avia-img-lazy-loading-216\"  width=\"448\" height=\"333\" src=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam-1.jpg\" title='kernansquillec_dam' alt='' srcset=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam-1.jpg 448w, https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam-1-300x223.jpg 300w\" sizes=\"auto, (max-width: 448px) 100vw, 448px\" \/><\/div><\/a><a href=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam_decommissioning_cc_afp_archives-2.jpg\" data-rel='gallery-1' data-prev-img='https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam_decommissioning_cc_afp_archives-2.jpg' class='first_thumb lightbox ' data-onclick='2' title='removal of the Kernansquillec dam \u00a9 AFP\/Archives'  itemprop=\"thumbnailUrl\"  ><img decoding=\"async\" fetchpriority=\"high\" class=\"wp-image-6752 avia-img-lazy-loading-not-6752\"  data-avia-tooltip='removal of the Kernansquillec dam \u00a9 AFP\/Archives' src=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam_decommissioning_cc_afp_archives-2.jpg\" width=\"300\" height=\"199\"  title='kernansquillec_dam_decommissioning_cc_afp_archives' alt='' \/><div class='big-prev-fake'><img decoding=\"async\" loading=\"lazy\" class=\"wp-image-6752 avia-img-lazy-loading-6752\"  width=\"300\" height=\"199\" src=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_dam_decommissioning_cc_afp_archives-2.jpg\" title='kernansquillec_dam_decommissioning_cc_afp_archives' alt='' \/><\/div><\/a><a href=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after_cc_onema-1.jpg\" data-srcset=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after_cc_onema-1.jpg 640w, https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after_cc_onema-1-300x225.jpg 300w\" data-sizes=\"(max-width: 640px) 100vw, 640px\" data-rel='gallery-1' data-prev-img='https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after_cc_onema-1-495x400.jpg' class='first_thumb lightbox ' data-onclick='3' title='Site of the former dam in October 2009 \u00a9 Onema'  itemprop=\"thumbnailUrl\"  ><img decoding=\"async\" fetchpriority=\"high\" class=\"wp-image-217 avia-img-lazy-loading-not-217\"  data-avia-tooltip='Site of the former dam in October 2009 \u00a9 Onema' src=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after_cc_onema-1.jpg\" width=\"640\" height=\"480\"  title='kernansquillec_after_cc_onema' alt='' srcset=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after_cc_onema-1.jpg 640w, https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after_cc_onema-1-300x225.jpg 300w\" sizes=\"(max-width: 640px) 100vw, 640px\" \/><div class='big-prev-fake'><img decoding=\"async\" loading=\"lazy\" class=\"wp-image-217 avia-img-lazy-loading-217\"  width=\"495\" height=\"400\" src=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after_cc_onema-1-495x400.jpg\" title='kernansquillec_after_cc_onema' alt='' \/><\/div><\/a><a href=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after2_cc_onema-2.jpg\" data-srcset=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after2_cc_onema-2.jpg 640w, https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after2_cc_onema-2-300x225.jpg 300w\" data-sizes=\"(max-width: 640px) 100vw, 640px\" data-rel='gallery-1' data-prev-img='https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after2_cc_onema-2-495x400.jpg' class='first_thumb lightbox ' data-onclick='4' title='The L\u00e9guer within the former reservoir area in October 2009 \u00a9 Onema'  itemprop=\"thumbnailUrl\"  ><img decoding=\"async\" fetchpriority=\"high\" class=\"wp-image-6751 avia-img-lazy-loading-not-6751\"  data-avia-tooltip='The L\u00e9guer within the former reservoir area in October 2009 \u00a9 Onema' src=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after2_cc_onema-2.jpg\" width=\"640\" height=\"480\"  title='kernansquillec_after2_cc_onema' alt='' srcset=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after2_cc_onema-2.jpg 640w, https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after2_cc_onema-2-300x225.jpg 300w\" sizes=\"(max-width: 640px) 100vw, 640px\" \/><div class='big-prev-fake'><img decoding=\"async\" loading=\"lazy\" class=\"wp-image-6751 avia-img-lazy-loading-6751\"  width=\"495\" height=\"400\" src=\"https:\/\/www.ern.org\/wp-content\/uploads\/2016\/11\/Kernansquillec_after2_cc_onema-2-495x400.jpg\" title='kernansquillec_after2_cc_onema' alt='' \/><\/div><\/a><\/div><\/div><\/div>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-n2f62-96f8ec10988e1f102a2db0c121e24386\">\n.flex_column.av-n2f62-96f8ec10988e1f102a2db0c121e24386{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-n2f62-96f8ec10988e1f102a2db0c121e24386 av_one_half  avia-builder-el-12  el_after_av_one_half  el_before_av_one_half  first flex_column_div av-zero-column-padding  column-top-margin'     ><section  class='av_textblock_section av-9u63u-765efd6e0a0c9fe672c8e76f8a8e0107 '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><p style=\"text-align: right;\"><a href=\"http:\/\/www.ern.org\/fr\/effacement-du-barrage-de-maisons-rouges\/\">Effacement pr\u00e9c\u00e9dent<\/a><br \/>\n<a href=\"http:\/\/www.ern.org\/fr\/effacement-du-barrage-de-maisons-rouges\/\">&lt;- &#8211; &#8211; &#8211; &#8211; &#8211; &#8211; &#8211; &#8211; &#8211; &#8211;<\/a><\/p>\n<\/div><\/section><\/div>\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-e86dm-f23241b4a981c59b6944ec19f35e3350\">\n.flex_column.av-e86dm-f23241b4a981c59b6944ec19f35e3350{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-e86dm-f23241b4a981c59b6944ec19f35e3350 av_one_half  avia-builder-el-14  el_after_av_one_half  avia-builder-el-last  flex_column_div av-zero-column-padding  column-top-margin'     ><\/div><\/p>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":5,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-138","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.ern.org\/fr\/wp-json\/wp\/v2\/pages\/138","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ern.org\/fr\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.ern.org\/fr\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.ern.org\/fr\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ern.org\/fr\/wp-json\/wp\/v2\/comments?post=138"}],"version-history":[{"count":0,"href":"https:\/\/www.ern.org\/fr\/wp-json\/wp\/v2\/pages\/138\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.ern.org\/fr\/wp-json\/wp\/v2\/media?parent=138"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}