The Comeback of Atlantic Salmon in the Orne River : Result of 10 Years of Dam Removal Projects Dam Removal Europe Workshop
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The comeback of Atlantic Salmon in the Orne river : result of 10 years of dam removal projects Dam Removal Europe Workshop Birmingham – September 25th 2017 The Orne river Watershed Dam Removal Europe Workshop 2017 5 migratory species Dam Removal Europe Workshop 2017 The Orne river A 177 km coastal river 1700 km of rivers in the watershed Important slope (many spawning and growing areas) PRIORITY AXIS FOR ECOLOGICAL CONTINUITY RESTORATION Dam Removal Europe Workshop 2017 The Orne river 140 120 : Spawning areas 100 80 60 Altitude (m) 40 20 0 90 78 76 72 68 54 47 31 29 17 Distance to the sea (km) Dam Removal Europe Workshop 2017 Different issues Carte BV Orne ouvrages / villes • 38 classified Dams and weirs • Industrial pollution • Agricultural pollution Extinction of the Salmon in the 30’ Dam Removal Europe Workshop 2017 Rabodange Saint-Philbert La Courbe Pontécoulant Dam Removal Europe Workshop 2017 Maizet Pont d’Ouilly Le Hom Danet Dam Removal Europe Workshop 2017 : Fish pass (8) : Passable by Salmon / ruined : Removed dams (8) : unpassable (1) Dam Removal Europe Workshop 2017 A dam removal example L’Orne renait à l’Enfernay (15 sec video link) Dam Removal Europe Workshop 2017 The comeback of Atlantic Salmon Upstream migration followed since 1980 Dam Removal Europe Workshop 2017 History of Salmon of Salmon 800 700 R² = 0,94 600 upstream 500 Dam Removal Europe Workshop 2017 Workshop Europe Dam Removal travauxtravaux réaménagement réaménagement 400 EffectifsEffectifs 300 REPEUPLEMENT REPEUPLEMENT REPEUPLEMENT souchesoucheGaves Gaves 200 migration 100 0 2016 2016 2015 2015 2014 2014 2013 2013 2012 2012 2011 2011 2010 2010 2009 2009 2008 2008 2007 2007 2006 2006 2005 2005 2004 2004 2003 2003 2002 2002 2001 2001 2000 2000 1999 1999 1998 1998 1997 1997 1996 1996 1995 1995 1994 1994 See you at lunch to watch the movie Dam Removal Europe Workshop 2017 Example of a dam removal project in urban environment : The Druance River Dam Removal Europe Workshop Birmingham – September 25th 2017 Normandie Grands Migrateurs NGO borned in 2015 – 2 employees Created by – The 3 fishing federation of Low Normandy It aims to – Restore aquatic environment and ecological continuity – Contribute to protect and develop migratory fish populations Dam Removal Europe Workshop 2017 Study site CAEN Dam Removal Europe Workshop 2017 Study site Current situation – 500 m of rectified river crossing the city – 3 weirs (2 useless and 1 used by General Electric for pumping in case of fire) – GE factory is implanted on the « confluence island » GE factory Dam Removal Europe Workshop 2017 Why a river restoration project ? Dam Removal Europe Workshop 2017 Why a river restoration project ? RESTORE ECOLOGICAL CONTINUITY AND HABITATS FOR MIGRATORY SPECIES Dam Removal Europe Workshop 2017 Solutions ideas An environmental design office has been selected to perform the study ? Dam Removal Europe Workshop 2017 Thank you for listening Dam Removal Europe Workshop 2017.