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 upstream migration
800
700
R² = 0,94
600
500 travaux réaménagement
400 Effectifs
300 REPEUPLEMENT REPEUPLEMENT soucheGaves
200
100
0
2016
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1995 1994
Dam Removal Europe Workshop 2017 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