June 2011

This report evaluates how three different Mersey Tidal Power scheme options could potentially affect the extent and quality of the habitats that support birds within the Mersey Estuary SPA by looking at SPA sub-features, the time that birds would have available for feeding within these habitats and the potential effects of the proposed schemes on WFD biological elements. This has been undertaken based on hydrodynamic modelling conducted for specific operational regimes for each of the schemes. Using specialist assessments and expert opinion, this report assesses potential effects on a range of ecological attributes used to assess the structure and function (and hence integrity) of the Mersey Estuary SPA.