DECC SEVERN TIDAL POWER - SEA ENVIRONMENTAL REPORT May 2010 Prepared by Prepared for Parsons Brinckerhoff Ltd DECC Queen Victoria House 3 Whitehall Place Redland Hill London Bristol SW1A 2HD BS6 6US In association with Black & Veatch Ltd Report Title : Severn Tidal Power - SEA Environmental Report Report Status : FINAL Date : May 2010 Prepared by : Lara Ball (BV) and Ed Ferguson (BV) Checked by : David Keiller (BV), Delyth Toghill (PB), Ursula Bycroft (BV), Paul Tarrant (BV). Approved by : Tom Matthewson (BV) Revision Status Date Issued 1-4 Internal drafts Various DECC and Environmental and 5 19 Mar 2010 Regional Workstreams review 6 DECC review 23 Apr 2010 7 Final 30 Apr 2010 Final with additions to 8 05 May 2010 Waterbird effects © Crown Copyright 2010 CONTENTS ABBREVIATIONS III NON TECHNICAL SUMMARY VII SECTION 1 1 BACKGROUND 1 1.1 Severn Tidal Power Feasibility Study 3 1.2 Strategic Environmental Assessment 3 1.3 Purpose and structure of this Environmental Report 4 1.4 Authors of this report 6 SECTION 2 7 APPROACH ADOPTED 7 2.1 Scope and structure of the SEA 9 2.2 Approach adopted in the SEA 10 2.3 Consultation 12 2.4 Difficulties encountered in compiling information or carrying out the assessment 15 SECTION 3 17 BASELINE ENVIRONMENT AND SEA OBJECTIVES 17 3.1 Other plans and programmes 19 3.2 Current state of the environment and likely evolution thereof 20 3.3 Existing environmental problems 55 3.4 Assumptions, limitations and uncertainty 58 3.5 SEA objectives 61 SECTION 4 63 PLAN ALTERNATIVE OPTIONS 63 4.1 Identifying the alternative options 65 4.2 Alternative options 67 SECTION 5 77 LIKELY SIGNIFICANT EFFECTS ON THE ENVIRONMENT AND MEASURES TO PREVENT, REDUCE AND AS FULLY AS POSSIBLE OFFSET ANY SIGNIFICANT ADVERSE EFFECTS 77 5.1 How the assessment was undertaken 79 5.2 Likely significant effects on the environment 88 Severn Tidal Power SEA – Environmental Report May 2010 Page i 5.3 Assumptions, limitations and uncertainty 158 5.4 Measures to prevent, reduce and as fully as possible offset any significant adverse effects on the environment 160 SECTION 6 171 SEA OBJECTIVES COMPARISON OF ALTERNATIVE OPTIONS 171 6.1 Performance of alternative options in relation to SEA objectives 173 SECTION 7 181 IMPLEMENTATION 181 7.1 Monitoring measures 183 7.2 Suggestions for further research to inform the environmental assessment of tidal power schemes on the Severn Estuary 184 SECTION 8 189 GLOSSARY 189 SECTION 9 199 REFERENCES 199 SECTION 10 205 APPENDICES 205 10.1 Appendix 1: Theme Papers and Topic Papers and associated annexes 209 10.2 Appendix 2: Stages in the SEA process and how they were undertaken in the Severn Tidal Power SEA 215 10.3 Appendix 3: Potentially significant issues identified during Phase One (Scoping) and where these have been addressed during Phase Two 219 10.4 Appendix 4: Organisations represented in the SEA Steering Group 223 10.5 Appendix 5: SEA objectives, assessment criteria and indicators 225 10.6 Appendix 6: Executive summary for each of the ten alternative options identified during Phase One 239 10.7 Appendix 7: Severn Tidal Power SEA environmental receptors 243 10.8 Appendix 8: Approach to identifying the significant effects of the alternative options 249 10.9 Appendix 9: Summary of Likely Significant Effects of the Alternative Options 257 10.10 Appendix 10: Log of measures to prevent, reduce and as fully as possible offset any significant adverse effects on the environment of implementing the plan or programme 281 10.11 Appendix 11: Summary of how each alternative option performs in relation to the SEA objectives 345 Severn Tidal Power SEA – Environmental Report May 2010 Page ii ABBREVIATIONS Severn Tidal Power SEA – Environmental Report May 2010 Page iii ABBREVIATIONS The following abbreviations are used in this Environmental Report: ABP Associated British Ports AONB Area of Outstanding Natural Beauty ASMITA Aggregated Scale Morphological Interaction between a Tidal inlet system and the Adjacent coast (see also Glossary) BV Black & Veatch Ltd. BAP Biodiversity Action Plan BoCC Birds of Conservation Concern BTO British Trust for Ornithology CHaMP Coastal Habitat Management Plan CCW Countryside Council for Wales CO2 Carbon Dioxide CSO Combined Sewer Overflow DECC Department of Energy and Climate Change Defra Department for Environment, Food and Rural Affairs DoE Department of Energy DTI Department of Trade and Industry EC European Commission EEC European Economic Community EIA Environmental Impact Assessment ELC European Landscape Convention ETSU Energy Technology Support Unit EU European Union FTE Full Time Equivalent GCR Geological Conservation Review GHG Greenhouse Gasses GIS Geographical Information System ha Hectare HAM Habitat Association Model HABMAP Habitat Mapping (see also Glossary) HAT Highest Astronomical Tide HRA Habitats Regulations Assessment HRW HR Wallingford IBM Individual Based Model ICES International Council for the Exploration of the Sea IMADP Interim Marine Aggregate Dredging Policy IOS Institute of Oceanographic Sciences JNCC Joint Nature Conservation Committee LAT Lowest Astronomical Tide LiDAR Light Detection And Ranging LNR Local Nature Reserve LOHIW Landscape of Outstanding Historic Interest in Wales MAGIC Multi-Agency Geographic Information for the Countryside Mm3 Million Metres Cubed MW Megawatt MSOA Middle Layer Super Output Area (see also Glossary) NAEI National Atmospheric Emissions Inventory NBN National Biodiversity Network NNR National Nature Reserve NO2 Nitrogen Dioxide NSR Noise Sensitive Receptor ODPM Office of the Deputy Prime Minister Severn Tidal Power SEA – Environmental Report May 2010 Page v ODR Options Definition Report PB Parsons Brinckerhoff Ltd PM10 Particulate matter of 10 micrometers diameter or less PPG Planning Policy Guidance PPS Planning Policy Statement PWS Public Water Supply REIS Regional Economic Impact Study RQO River Quality Objectives SAC Special Area of Conservation SEA Strategic Environmental Assessment SEFRMS Severn Estuary Flood Risk Management Strategy SETS Severn Embryonic Technologies Scheme SI Statutory Instrument SMP Shoreline Management Plan SNCI Site of Nature Conservation Interest SO2 Sulphur Dioxide SPA Special Protection Area SPZ Source Protection Zone SSSI Site of Special Scientific Interest STP Severn Tidal Power STPG Severn Tidal Power Group SWRDA South West Regional Development Agency TWh Terrawatt hours UK United Kingdom UKBAP UK Biodiversity Action Plan UKCP09 United Kingdom Climate Projections 2009 WAG Welsh Assembly Government WeBS Wetland Bird Survey WFD Water Framework Directive WwTW Wastewater Treatment Works ZTV Zone of Theoretical Visibility Severn Tidal Power SEA – Environmental Report May 2010 Page vi NON TECHNICAL SUMMARY Severn Tidal Power SEA – Environmental Report May 2010 Page vii SEVERN TIDAL POWER – SEA ENVIRONMENTAL REPORT NON TECHNICAL SUMMARY N.1 Introduction N.1.1 The Government published the terms of reference for a two-year feasibility study on harnessing the renewable energy from the tidal range of the Severn Estuary in January 2008. This work has been carried out by a cross-Government team led from the Department of Energy and Climate Change (DECC), including representatives of the Department for the Environment, Food and Rural Affairs (Defra), the Welsh Assembly Government (WAG) and the South West Regional Development Agency (SWRDA), taking external advice as necessary and engaging stakeholders and the wider public. N.1.2 The aim of the Severn Tidal Power (STP) Feasibility Study was to investigate whether the Government could support a tidal power scheme in the Severn and, if so, on what terms. This is the Non Technical Summary of the Strategic Environmental Assessment (SEA) for the Severn Tidal Power Feasibility Study. It informs Government decision-making. Key messages within the non technical summary are provided in boxes such as this. N.2 Contents of Environment Report N.2.1 Strategic Environmental Assessment (SEA) is the term used to describe environmental assessment as applied to plans and programmes, under the European Union (EU) ‘SEA’ Directive. This SEA has been carried out in support of the STP Feasibility Study, and its purpose is to identify, describe and evaluate the likely significant effects on the environment of a tidal power project within the Severn Estuary. The preparation of this Environmental Report has included consultation with the public, key stakeholders and statutory authorities. N.2.2 The contents of this Environmental Report are set out in Table N.1, and were the subject of a scoping consultation exercise conducted in 2009. This report, alongside others being prepared within the Feasibility Study, will inform the Government’s decision on whether or not it could support a tidal power project within the Severn Estuary. Table N.1 Report structure Section Description 1. Background An overview of the STP Feasibility Study and the objectives of the plan. Purpose of the SEA. An outline of the contents of the Environmental Report. 2. Approach adopted Scope and structure of the SEA. Approach adopted in the SEA. Overview of the consultation undertaken throughout the SEA process. The difficulties encountered in compiling information or carrying out the assessment. 3. Baseline Other international, national, regional and local plans and environment and SEA programmes, and relevant environmental protection objectives and objectives how these have been taken into account. Severn Tidal Power SEA – Environmental Report May 2010 Page ix Section Description Baseline characteristics