Development of the Strasbourg Fish Pass is part of a series of such passes built by the EDF Group at Iffezheim, Gambsheim and Brisach, environmental projects at Kembs and activities carried out with its partners (Saumon Rhin, fishing associations and Petite Camargue Alsacienne) to develop the Rhine Salmon genetic strain, as well as undertakings already given by EDF concerning the Gerstheim fish pass.
The site for this fish pass is already under construction and it is being built in accordance with the latest ecological and technical criteria.
The new EDF Fish Pass in Strasbourg will comprise :
- a double entrance: one entrance for the ‘long-distance’ migratory fish and one for local species, with a total flow of 15 cu. m./second
- a succession of 18 concrete pools,
- followed by a pseudo-natural river, 500 metres long, 5.5 metres wide and fed by a flow of 1.2 cu. m./second,
- and then a second succession of 18 concrete pools.
The overall effect of these constructions will be to enable the fish to pass through a height difference of 13 metres.
How it works: The fish are drawn by the current. For a watercourse the size of the Rhine at Strasbourg, it takes 15 cubic metres of water per second to draw the fish towards the facility.
Once they are in the pools or the hydroelectric power station bypass river, a flow of 1.2 cubic metres per second is enough to enable them to climb upstream of the construction. It is not therefore necessary to build a structure that is calibrated to produce a flow of 15 cubic metres per second; this would be excessive in terms of volume and cost.
The flow that is required to draw the fish but does not feed into the river can therefore be used to drive a turbine which in turn produces electricity without generating any greenhouse gases.
A hydroelectric generator with an output of 1.5 megawatts will drive the water intended to draw the fish to the pass entrances, to produce electricity. Up to 13.8 cubic metres per second will pass through two turbines that have been integrated into the civil engineering of the construction.
Scientific monitoring A special building will be fitted out to enable automated counting of fish using the pass. A video camera will be activated automatically by a movement detector. The images recorded will then be analysed.
Exemplary features of the plan that has been implemented
The scale of the project, in particular the creation of a 500 metre pseudo-natural river
The reception facility which enables the general public to find out about the project
Exemplary features of the technical solutions implemented
Constructing a building site within a restricted space
List of skills that can be seen on the site
First feasibility study launched in 2008, followed by a Preliminary Design Study and then the Detailed Design Study.
All these studies were conducted by EDF’s engineering division, with the support of EDF/R&D.
- The Preliminary Design Study and Detailed Design Study were approved in 2011.
- Beginning of the implementation phase: 2012
- Commencement of operations planned for 2015
A budget of 15 million euros, with 30% financial support from the Agence de l’Eau Rhin Meuse
Immediate environment The EDF hydroelectric power station in Strasbourg came into operation in 1970. It consists of six ‘Bulbe’ turbine generators with an output of 150 megawatts from a drop of 13.25 metres. A dam with six openings (each opening being 20 metres wide)
The locks directly alongside the generating plant and operated by EDF have the following characteristics: a large chamber measuring 190 metres by 24 metres, a small chamber measuring 190 metres by 12 metres, and a depth of 17.95 metres. An observation platform overlooking the chambers enables the public to watch the locks in operation.
Annual production by the power station in 2013: 915 MWh (million kilowatt hours), ad hoc management
Ile du Rohrschollen (part of which is a national nature reserve)
EDF UNITE DE PRODUCTION EST
54 Avenue Schuman - BP 1007, 68050 Mulhouse
Players involved and their roles
EDF UNITE DE PRODUCTION EST
EDF CENTRE D'INGENIERIE HYDRAULIQUE, EDF R&D
AGENCE DE L'EAU, DREAL ALSACE, ONEMA