Strategy Appraisal Report Authority scheme B&H4 reference Defra/WAG LDW CPW/2042 number Promoting Brighton and Hove City Council authority Strategy Brighton Marina to River Adur Flood and Coastal Erosion name Risk Management Strategy Review Brighton Seafront, February 2014 Date November 2014 Version 3.0 StAR for Brighton Marina to River Adur Flood and Coastal Erosion Risk Management Strategy Review Version Status Signed off by: Date signed Date issued 1.0 Final August 2014 2.0 Final (following LPRG October 2014 pre -brief comments) 3.0 Final (following LPRG November 2014 meeting) Template version – April 2011 Title Brighton Marina to River Adur Flood and Coastal Erosion Risk Management Strategy Review No. CPW/2042 Status: Version 3.0 Issue Date: Nov 2014 Page i CONTENTS For technical approval of the business case .................................................................iv Non-financial scheme of delegation ..............................................................................iv Approval history sheet .................................................................................................. v 1 EXECUTIVE SUMMARY .............................................................................................. 1 1.1 Introduction and Background ................................................................................ 1 1.2 Problem ................................................................................................................ 1 1.3 Options considered .............................................................................................. 2 1.4 Recommended Strategy ....................................................................................... 3 1.5 Economic Summary ............................................................................................. 3 1.6 Environmental and Social Considerations ............................................................ 3 1.7 Implementation and Outcome Measure score ...................................................... 4 1.8 Contributions and Funding ................................................................................... 4 1.9 Key Project Risks ................................................................................................. 5 1.10 Recommendations ............................................................................................... 5 1.11 Directors’ Briefing Paper....................................................................................... 6 2 INTRODUCTION AND BACKGROUND ....................................................................... 8 2.1 Purpose of this report ........................................................................................... 8 2.2 Background .......................................................................................................... 8 2.3 Environmental and Social Considerations ............................................................ 9 2.4 Current approach to coastal erosion and flood risk management ....................... 12 3 PROBLEM DEFINITION AND OBJECTIVES ............................................................. 14 3.1 Outline of the problem ........................................................................................ 14 3.2 Consequences of doing nothing ......................................................................... 18 3.3 Strategic issues .................................................................................................. 19 3.4 Key constraints ................................................................................................... 20 3.5 Objectives .......................................................................................................... 21 4 OPTIONS FOR MANAGING FLOOD AND COASTAL EROSION RISK .................... 21 4.1 Potential FCERM measures ............................................................................... 21 4.2 Long list of options ............................................................................................. 22 4.3 Options rejected at preliminary stage ................................................................. 24 4.4 Options short-listed for appraisal ........................................................................ 24 5 OPTIONS APPRAISAL AND COMPARISON ............................................................ 29 5.1 Technical issues ................................................................................................. 29 5.2 Environmental assessment ................................................................................ 30 5.3 Social and community impacts ........................................................................... 32 5.4 Option costs ....................................................................................................... 33 5.5 Options benefits (Damages avoided).................................................................. 34 6 SELECTION AND DETAILS OF THE PREFERRED OPTION ................................... 35 6.1 Selecting the preferred option ............................................................................ 35 6.2 Sensitivity testing................................................................................................ 36 6.3 Details of the preferred option ............................................................................ 37 6.4 Summary of preferred strategy ........................................................................... 43 7 IMPLEMENTATION .................................................................................................... 44 7.1 Project planning ................................................................................................. 44 7.2 Procurement strategy ......................................................................................... 46 7.3 Delivery risks ...................................................................................................... 47 Title Brighton Marina to River Adur Flood and Coastal Erosion Risk Management Strategy Review No. CPW/2042 Status: Version 3.0 Issue Date: Nov 2014 Page ii TABLES Table 1.1 Summary of Preferred Options and Economic Appraisal 3 Table 1.2 Annualised cash spend profile (Units 1, 2 & 3) 4 Table 1.3 Breakdown of Contributions and Funding 4 Table 1.4 Key Project Risks 5 Table 3.1 Properties at risk from flooding and erosion under NAI 15 Table 3.2 Standard of Protection on Open Coast 15 Table 4.1 Unit 1 (Shoreham Locked Section) 22 Table 4.2 Unit 2 (Open Coast) 23 Table 4.3 Unit 3 (Brighton Marina) 24 Table 5.1 Key environmental impacts, mitigation and opportunities 31 Table 5.2 Summary of options present value (PV) costs (£k) – Unit 1 33 Table 5.3 Summary of options present value (PV) costs (£k) – Unit 2 34 Table 5.4 Summary of options present value (PV) costs (£k) – Unit 3 34 Table 5.5 Summary of options present value (PV) damages and benefits (£k) 35 Table 6.1 Benefit-cost assessment for Units 1 and 2 36 Table 6.2 Benefit-cost assessment for Unit 3 36 Table 6.3 Summary of Preferred Options for Strategy 38 Table 6.4 WFD water body assessment 40 Table 6.5 Costs of Preferred Option (Cash with Optimism Bias excluded) 41 Table 6.6 Breakdown of Contributions and Funding 42 Table 6.7 Breakdown of Benefits and Costs by Unit and Property Type 42 Table 6.8 Summary of preferred strategy 43 Table 7.1 Key dates 44 Table 7.2 Annualised cash spend profile (Units 1, 2 & 3) 45 Table 7.3 Medium term outcome measures contributions 46 Table 7.4 High level risk schedule and mitigation 47 APPENDICES Appendix A Project Appraisal Data Sheet Appendix B List of Reports Appendix C Photographs Appendix D Details of Proposed Works Appendix E Economic Appraisal Appendix F Cost Breakdown Appendix G Strategy Delivery Plan Appendix H Condition Survey Report Appendix I Coastal Processes Report Appendix J NAI Report Appendix K Options Report Appendix L Appraisal Summary Tables Appendix M Risk Register Appendix N List of Consultees Appendix O Strategic Environmental Assessment Appendix P Natural England and Adur & Worthing Councils’ Letters of Support Title Brighton Marina to River Adur Flood and Coastal Erosion Risk Management Strategy Review No. CPW/2042 Status: Version 3.0 Issue Date: Nov 2014 Page iii For technical approval of the business case Brighton and Hove City Council Project name: Brighton Marina to River Adur Flood and Coastal Erosion Risk Management Strategy Review Approval Value: £159,000k Sponsoring Director: Geoff Raw Strategic Director Non-financial scheme of delegation Part 11 of the Non-financial scheme of delegation states that approval of FCERM Strategies/Complex Change Projects, following recommendation for approval from the Large Projects Review Group, is required from the Regional Director or Director, Wales and Director of Operations. Title Brighton Marina to River Adur Flood and Coastal Erosion Risk Management Strategy Review No. CPW/2042 Status: Version 3.0 Issue Date: Nov 2014 Page iv Approval history sheet APPROVAL HISTORY SHEET (AHS) 1. Submission for review (to be completed by team) Project Title: Brighton Marina to River Adur Flood and Coastal Erosion Risk Management Strategy Project Code: CPW/2042 Review Project Manager: Martin Eade Date of Submission: Aug 2014 Lead Authority: Brighton and Hove City Council Version No: 1.0 Consultant Project Manager: Jon Denner Consultant: CH2MHILL (Halcrow) The following confirm that the documentation is ready for submission to PAB or LPRG. The Project Executive has ensured