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    -Pascal Bonnetain \ Local water commission of the Ardèche RBMP
    "The first river contract for the Ardèche river was in 1984..."

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    Why is it needed to restore river continuity?

    In France, more than 60,000 structures1 - dams, locks, weirs and mills – have been recorded on
    rivers and are potential obstacles to river continuity.


  • Restoring ecological continuity

    Implementation of the national action plan to restore the ecological continuity of rivers is a major challenge requiring coordination between all water stakeholders.

    In addition to drawing up the national inventory of obstacles to river flow and assisting in identifying the most serious cases, Onema informs and encourages the various water stakeholders to launch projects to restore ecological continuity, notably by eliminating abandoned installations.

    Throughout France, Onema personnel provide opinions on the impact of obstacles, advise on the possible solutions and make their considerable technical know-how available during monitoring of the work.

    In order to mobilise all the public entities involved in the national plan to restore ecological continuity, notably the State services and the Water agencies, Onema and the Ecology ministry organised a full day of information meetings. Over 200 people met in Paris to discuss the five main parts of the plan and a number of original implementation strategies.


    Onema in the Auvergne-Limousin region : Restoring ecological continuity by eliminating four installations on the Dore river

    In the Puy-de-Dôme department, the basin of the middle section of the Dore river is riddled with some 300 watermills on just 200 kilometres of river. An obstacle every kilometre breaks up the ecological continuity of the Dore and its tributaries, most of which are classed as "rivers for migratory fish" as per article L. 432.6 in the Environmental code. Only two to three percent of the mills still operate today. In 2010, four mills were totally or partially removed under agreements with the owners who renounced their milling rights. Two installations were equipped with fishways for migratory fish. The work to remove the mills was funded by the Loire-Brittany water agency, the regional council and local governments. It was carried out as part of the maintenance and restoration contract for the middle section of the Dore river.

    Onema personnel provided their technical and legal know-how in setting up the priorities for the work, adapting the technical specifications and monitoring execution. Restoration of the ecological continuity of the Dore river is just beginning. Onema makes every effort to assist the various stakeholders in determining the future priorities in accordance with the Grenelle environmental agreement.

    Contact : - Onema Auvergne-Limousin regional office