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Restoration of ecological continuity is essential to efforts to restore good water status 

Damage to the physical characteristics of rivers endangers the goal of restoring the good ecological status of water by 2015. The main challenge, i.e. restore ecological continuity and river hydromorphology, will be met only by combining incentives and legal action.

River channelling and obstacles to flow may hinder achieving good ecological status by 2015 for half of all water bodies. Considerable efforts must be undertaken to bring existing structures in rivers up to current standards and to launch major projects to restore the hydromorphology and continuity of rivers. The success of these future efforts will depend on good coordination between four types of stakeholders, 1) local owners undertaking restoration work, 2) the Water agencies which have increased the funds invested in restoration work, 3) the local State services carrying out policing activities and 4) the Onema territorial units that provide technical support to diagnose impacts and to develop solutions, as well as run inspections in the field.
Now that the programmes of measures have published the list of restoration projects and the national action plan to restore the ecological continuity of rivers has been launched, the challenge will be to encourage the owners of structures to undertake increasing numbers of restoration projects.

Contact: alexis.delaunay@onema.fr

Toward harmonised monitoring of restoration projects

Due to a lack of serious monitoring and enough experience, it is difficult to evaluate rigorously the ecological benefits of projects carried out over the past 15 years. That is why Onema and the Water agencies are currently working on harmonising monitoring procedures for future restoration projects.

Elimination of five ponds in the Côte d'Or department

The Val des Choues stream lies in a public biological reserve zone and is part of a Natura 2000 site. In 1968, a set of five artificial ponds were created to raise salmon, but five years later, the unprofitable venture was abandoned. The fragmentation of the stream produced a number of negative impacts including disconnection from the stream itself, changes in temperature, obstacles to free travel, the arrival of undesirable fish species and difficulties for the population of white-clawed crayfish. The elimination of the five ponds was undertaken in June 2006, in the framework of the European Life Nature programme. The goals were to restore the stream to its original bed, restore its continuity, increase the habitat zone for the white-clawed crayfish and to restore habitats in general. Funding was received from an array of sources including the EU, the Ecology ministry, the Seine-Normandie and Rhône-Méditerranée-Corse Water agencies, the regional council and the Morvan regional nature park. The Morvan park and Onema also provided technical support. Project management is provided by the National forestry agency. Scientific monitoring was set up with, prior to the work, a study on stream status both upstream and downstream of the ponds and, following the work, monitoring of the morphological and biological changes in the stream. Initial results are encouraging. The stream has cut out its bed over virtually the entire restored distance and adopted a slightly sinuous path. The bed is rapidly reverting to the former habitat conditions. In less than three months, the former ponds have dried and been covered by natural vegetation that stabilises the mud flats. The local fauna is in the process of returning to the stream and white-clawed crayfish are now present in the upstream section of the restored area.

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