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The Severn Tidal Power Feasibility Study is considering a number of proposed electricity generation schemes, not barrages exclusively.
Full consideration is being given to potential impacts of a tidal power scheme on migratory and estuarine fish. A strategic environmental assessment (SEA) is being undertaken, together with a strategic level habitats regulations assessment (HRA), the preliminary stage of which has already commenced. The HRA is being conducted under the terms of the habitats regulations, the instrument by which the habitats directive is translated into UK law. These assessments include all designated migratory fish species of the Severn estuary and relevant tributaries including the rivers Usk and Wye.
Subject to internal review, preliminary studies on fish impacts and the preliminary HRA screening will be published in the new year, alongside public consultation on the scope of the strategic environmental assessment. Further studies are planned during 2009 and will be published later.