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Guide to the Environmental Impact Evaluation of Tidal Stream Technologies at Sea : GHYDRO

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Guide to the Environmental Impact Evaluation of Tidal Stream Technologies at Sea : GHYDRO Guide to the environmental impact evaluation of tidal stream technol- HEOS marine ogies at sea : GHYDRO Any reproduction or representation, in whole or in part, by any process whatsoever, of the pages pub- lished in the present document, done without the permission of France Energies Marines is illegal and would constitute a counterfeit. Only the following are permitted: 1) reproduction that is strictly for the purpose of the private use of the person making the copy and not intended for collective use, and 2) quotation of short passages that are justified as being for purposes of a scientific nature or for illustra- tion of the work in which they are incorporated (Law of July 1 1992 - art. L 122-4 and L 122-5 and Penal Code art. 425). Any citation of extracts or reproduction should cite the reference to this document in the form: France Energies Marines, Guide to the environmental impact evaluation of tidal stream technologies at sea, 2013. © 2013 France Energies Marines GHYDRO - 2 Table of contents Authors ..................................................................................................................................... 6 Contributors ............................................................................................................................. 6 Acronyms .................................................................................................................................. 7 Introduction .............................................................................................................................. 8 1. Tidal stream energy ..........................................................................................................13 1.1. Context ................................................................................................................... 13 1.2. Operating principle of a tidal stream park ............................................................ 14 1.3. Tidal stream technologies ...................................................................................... 15 1.4. Electric connections ............................................................................................... 19 1.5. Conclusions: specific needs for impact assessment ............................................... 25 1.6. Recommendations ................................................................................................. 25 2. Legal framework ...............................................................................................................26 2.1. Regulatory procedures applicable to tidal stream projects .................................. 26 2.2. The environmental assessment ............................................................................. 28 2.3. Specificities and difficulties of the environmental assessment of a tidal stream project ................................................................................................................................ 30 2.4. Recommendations ................................................................................................. 30 3. Consideration of usages ....................................................................................................31 3.1. The different potential usages, affected or not ............................................................. 31 3.2. Characterising the usages and assessing the impacts ................................................... 31 3.3. Fishing activities (professional and recreational) ...................................................... 32 Physical environment .......................................................................................................... 34 4. Seabed ...............................................................................................................................37 4.1. Description of the initial state ................................................................................ 37 4.2. Methods for the identification and analysis of potential ecological changes ........ 43 4.3. Identification of cumulative impacts ..................................................................... 50 GHYDRO - 3 4.4. Description of the environmental monitoring programme ................................... 51 4.5. Measures for impact mitigation ............................................................................. 53 4.6. Deficiencies and research programme .................................................................. 54 5. Oceanography ...................................................................................................................55 5.1. Description of the initial state ................................................................................ 55 5.2. Methods for identification and analysis of potential ecological changes .............. 62 5.3. Identification of cumulative impacts ..................................................................... 66 5.4. Description of the environmental monitoring programme ................................... 66 5.5. Measures for impact mitigation ............................................................................. 67 5.6. Deficiencies and research programmes ................................................................. 67 6. Underwater noise .............................................................................................................69 Overview of underwater noise ............................................................................................ 69 6.1. Description of the initial state .............................................................................. 72 6.2. Methods for identification and analysis of potential ecological changes ......... 81 6.3. Identification of cumulative impacts ..................................................................... 85 6.4. Description of the environmental monitoring programme ................................... 85 6.5. Impact avoidance and reduction measures ........................................................... 87 6.6. Deficiencies and research programmes ................................................................. 87 The potential impacts of the electromagnetic field (EMF) of the electric cables ....................89 Biological environment ........................................................................................................ 91 7. Benthos .............................................................................................................................94 7.1. Description of the initial state ................................................................................ 94 7.2. Methods for the identification and analysis of potential ecological changes ...... 104 7.3. Identification of cumulative impacts ................................................................... 108 7.4. Description of a environmental monitoring programme .................................... 108 7.5. Impact mitigation measures ................................................................................ 111 7.6. Deficiencies and research programmes ............................................................... 113 GHYDRO - 4 8. Fisheries ......................................................................................................................... 114 8.1. Description de l’état initial .................................................................................. 114 8.2. Methods of identification and analysis of potential ecological changes .............. 118 8.3. Identification of cumulative impacts ................................................................... 126 8.4. Description of the environmental monitoring programme ................................. 127 8.5. Mitigation of impacts ........................................................................................... 128 8.6. Research programs and target knowledge .......................................................... 129 9. Marine Mammals ............................................................................................................ 131 9.1. Description of the initial state ............................................................................ 132 9.2. Methods for identifying and analysing potential ecological changes ............. 135 9.3. Identification of cumulative impacts .................................................................. 141 9.4. Description of an environmental monitoring program ..................................... 141 9.5. Impact attenuation measurement ...................................................................... 147 9.6. Knowledge gaps and research programs .......................................................... 147 10. Birdlife ............................................................................................................................ 149 10.1. Description of the initial state .............................................................................. 149 10.2. Methods of identification and analysis of potential environmental changes ...... 151 10.3. Identification of cumulative impacts ................................................................... 154 10.4. Description of an environmental monitoring program ....................................... 154 10.5. Impact mitigation ................................................................................................. 158 10.6. Knowledge gaps and research programs ............................................................
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