A12 Chelmsford to A120 Widening Options Assessment Report
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A12 Chelmsford to A120 widening Options Assessment Report March 2016 A12 Chelmsford to A120 widening – Options Assessment Report Contents 1. Introduction ................................................................................................................................................ 1 1.1 Purpose of report ......................................................................................................................................... 1 1.2 Structure of report ........................................................................................................................................ 1 1.3 Background ................................................................................................................................................. 2 1.4 Overview of assessment ............................................................................................................................. 3 2. Policy and literature review ...................................................................................................................... 6 2.1 Introduction .................................................................................................................................................. 6 2.2 National policy ............................................................................................................................................. 7 2.3 Regional and local policy and guidance ...................................................................................................... 8 2.4 Recent studies and consultation ............................................................................................................... 11 3. Current situation ...................................................................................................................................... 14 3.1 Introduction ................................................................................................................................................ 14 3.2 Land use and demographics ..................................................................................................................... 14 3.3 Transport network ...................................................................................................................................... 17 3.4 Route performance .................................................................................................................................... 21 3.5 Environment .............................................................................................................................................. 31 3.6 Constraints and opportunities .................................................................................................................... 33 3.7 Summary ................................................................................................................................................... 34 4. Future situation ....................................................................................................................................... 35 4.1 Introduction ................................................................................................................................................ 35 4.2 Planned growth and infrastructure changes .............................................................................................. 35 4.3 Forecasting and scenario development .................................................................................................... 38 4.4 Future route performance .......................................................................................................................... 39 4.5 Summary ................................................................................................................................................... 42 5. Need for intervention .............................................................................................................................. 44 5.1 Introduction ................................................................................................................................................ 44 5.2 Current transport related problems ........................................................................................................... 44 5.3 Future transport related problems ............................................................................................................. 44 5.4 Impacts of no intervention on network ....................................................................................................... 45 5.5 Underlying drivers or causes ..................................................................................................................... 47 6. Objectives and area of impact ............................................................................................................... 48 6.1 Objectives .................................................................................................................................................. 48 6.2 Targets ...................................................................................................................................................... 48 6.3 Geographic area of impact ........................................................................................................................ 50 7. Option generation .................................................................................................................................... 52 7.1 Introduction ................................................................................................................................................ 52 7.2 Consultation and engagement process ..................................................................................................... 52 7.3 Option generation ...................................................................................................................................... 53 8. Option sifting ........................................................................................................................................... 57 8.1 Introduction ................................................................................................................................................ 57 8.2 Stage one: initial sift .................................................................................................................................. 57 ii A12 Chelmsford to A120 widening – Options Assessment Report 8.3 Stage two: early assessment and sifting process ..................................................................................... 60 8.4 Options for appraisal ................................................................................................................................. 62 9. Option assessment ................................................................................................................................. 65 9.1 Introduction ................................................................................................................................................ 65 9.2 Assessment methodology ......................................................................................................................... 65 9.3 Case 1: strategic fit .................................................................................................................................... 66 9.4 Case 2: Economics (value for money) ...................................................................................................... 70 9.5 Case 3: financial case ............................................................................................................................... 73 9.6 Case 4: commercial case .......................................................................................................................... 74 9.7 Case 5: management case ....................................................................................................................... 75 9.8 Better performing options .......................................................................................................................... 76 10. Summary and next steps ........................................................................................................................ 77 10.1 Summary ................................................................................................................................................... 77 10.2 Conclusions ............................................................................................................................................... 78 Appendix A. Glossary Appendix B. Expressway visualisation Appendix C. Pedestrian crossings of the A12 corridor Appendix D. Journey time analysis Appendix E. Capacity analysis Appendix F. Buffer index as a measure of journey time reliability Appendix G. Travel speed distributions Appendix H. Collision and incident data Appendix I. Environmental constraints plan Appendix J. Early assessment and sifting tool outputs Appendix K. Appraisal summary tables Appendix L. Sifting Spreadsheet iii A12 Chelmsford to A120 widening – Options Assessment Report 1. Introduction 1.1 Purpose of report This report relates to proposals in the East of England Area 6 (south) including schemes for the A12 between the M25 and Ipswich. This report presents the proposals for the