WELSH ASSEMBLY GOVERNMENT A40 WEST OF ST CLEARS ROUTE OPTIONS REPORT Volume 1 Parsons Brinckerhoff Ltd TACP BHC 29 Cathedral Road, 10 Park Grove, Suite 23 CARDIFF CARDIFF Coleridge House CF11 9HA CF10 3BN LONDON NW6 3QH Tel: 029 2082 7000 Tel: 029 2022 8666 Tel: 020 7372 2600 Fax: 029 2082 7001 Fax: 029 2039 4776 Fax: 020 7372 2662 A40 WEST OF ST CLEARS ROUTE OPTIONS REPORT AUTHORISATION SHEET Client: Welsh Assembly Government – Transport Directorate Project: A40 St Clears to Fishguard Study – REPORT Address: Cathays Park , CARDIFF CF10 3NQ PREPARED BY Name: P.R.Goddard Position: Associate Date: AGREED BY Name: O.G.Thomas Position: Associate Date: AUTHORISED FOR ISSUE Name: O.G.Thomas Position: Associate Date: DISTRIBUTION: Transport Directorate 2 Copies PB 1 Copy TACP 1 Copy H:\HHI\JOBS\43696 A40 St Clears to Fishguard\Reports\Options Report\ROR\ROR Vol1 Rev 10.doc December 2004 Page iii A40 WEST OF ST CLEARS ROUTE OPTIONS REPORT CONTENTS Page 1 INTRODUCTION 1 1.1 GENERAL INFORMATION. 1 1.2 THE COMMISSION BRIEF 1 1.3 SUPPORTING REPORTS AND RELEVANT INFORMATION 2 2 ROUTE OPTION ASSESSMENT AND APPRAISAL PROCESS 4 2.1 THE BRIEF 4 2.2 STAGE 1 ROUTE CORRIDOR ASSESSMENT AND APPRAISAL 4 2.3 STAGE 2 ROUTE OPTION ASSESSMENT AND APPRAISAL 5 2.3.1 Route Option Identification, Assessment and Appraisal 5 2.3.2 Objectives and Basic principles 5 2.3.3 Stage 2 Assessment and appraisal 5 2.4 VALUE ENGINEERING WORKSHOP 5 3 EXISTING ROUTE DESCRIPTION 7 3.1 CHAINAGES 7 3.2 TRAFFIC AND ACCIDENT DATA 7 3.3 DESCRIPTION OF THE LOCALITY 7 3.4 EXISTING HIGHWAY NETWORK 8 3.4.1 Sections A and B St Clears to Whitland Bypass and Whitland Bypass 8 3.4.2 Section C Whitland Bypass to Llanddewi Velfrey 10 3.4.3 Section D Llanddewi Velfrey to Penblewin 11 3.4.4 Section E Penblewin to Canaston Bridge 13 3.4.5 Sections F and G Canaston Bridge to Deep Lake Farm 15 3.4.6 Sections H and I Deep Lake Farm to Scotchwell Roundabout 17 3.5 TOPOGRAPHY, LAND USE AND OWNERSHIP, PROPERTY AND INDUSTRY 18 3.5.1 Topography 18 3.5.2 Land Use 18 3.5.3 Land Ownership 18 3.5.4 Special Land. 18 3.5.5 Property 19 3.5.6 Industry 19 3.6 CLIMATE 19 3.6.1 General 19 3.6.2 Rainfall 19 3.6.3 Winds 19 3.6.4 Temperature 19 3.6.5 Snow 20 3.6.6 Visibility 20 3.7 DRAINAGE 20 3.7.1 Flooding 20 3.7.2 Water Abstraction 21 3.8 GEOLOGY 21 3.8.1 Ground Conditions 21 3.8.2 Stratigraphical Description 21 H:\HHI\JOBS\43696 A40 St Clears to Fishguard\Reports\Options Report\ROR\ROR Vol1 Rev 10.doc December 2004 Page v A40 WEST OF ST CLEARS ROUTE OPTIONS REPORT 3.8.3 Solid Geology 22 3.8.4 Superficial Geology 23 3.9 MINING AND QUARRYING 23 3.10 PUBLIC UTILITIES 23 3.10.1 General 23 3.10.2 British Telecom 24 3.10.3 Transco 24 3.10.4 Welsh Water (Supply) 24 3.10.5 Welsh Water (Sewerage) 25 3.10.6 Western Power Distribution 25 3.10.7 Summary 25 3.11 ENVIRONMENTAL STATUS 25 3.11.1 General 25 3.11.2 Air Quality 25 3.11.3 Cultural Heritage 25 3.11.4 Ecology and Nature Conservation 26 3.11.5 Landscape 26 3.11.6 Land Use 26 3.11.7 Traffic Noise and Vibration 26 3.11.8 Pedestrians, Cyclists, Equestrians & Community 27 3.11.9 Vehicle Travellers 27 3.11.10 Water Quality & Drainage 27 3.11.11 Geology and Soils 28 3.12 STATUTORY DESIGNATED AREAS 28 3.12.1 National Park 28 3.12.2 Areas of Outstanding Natural Beauty 28 3.12.3 Sites of Special Scientific Interest (SSSI) 28 3.12.4 Candidate Special Areas of Conservation (cSAC) 29 3.13 PLANNING FACTORS 29 3.13.1 Outline 29 3.13.2 Framework 29 3.13.3 Pembrokeshire Joint Unitary Development Plan (JUDP) (Deposit Version 2002). 30 3.13.4 Carmarthenshire Unitary Development Plan – (Deposit Version, November 2002) 30 4 ENGINEERING INFORMATION AND PARAMETERS FOR ROUTE OPTION DEVELOPMENT 31 4.1 HIGHWAY STANDARDS 31 4.1.1 Option types 31 4.1.2 Highway Standards 31 4.1.3 Costs 33 4.1.4 Design Principles 33 4.2 PRELIMINARY CONSIDERATION OF STRUCTURES 34 4.2.1 Survey of Existing Structures 34 4.2.2 Strength of Existing Structures 34 4.2.3 Summary of Preliminary Consideration 35 4.3 JUNCTION STRATEGY 35 4.3.1 Junction types and their properties. 35 4.3.2 Junction Strategy to be adopted 37 4.3.3 Private Means of Access 38 4.4 BUILDABILITY ISSUES 38 5 ROUTE OPTION APPRAISAL 39 5.1 GENERAL 39 H:\HHI\JOBS\43696 A40 St Clears to Fishguard\Reports\Options Report\ROR\ROR Vol1 Rev 10.doc December 2004 Page vi A40 WEST OF ST CLEARS ROUTE OPTIONS REPORT 5.2 DO NOTHING / DO MINIMUM OPTION 39 6 DO SOMETHING OPTION - SINGLE CARRIAGEWAY STRATEGY 40 6.1 INTRODUCTION 40 6.1.1 Section A St Clears to Whitland Bypass 40 6.1.2 Section B Whitland Bypass 44 6.1.3 Section C Whitland Bypass to Llanddewi Velfrey 44 6.1.4 Section D Llanddewi Velfrey to Penblewin 44 6.1.5 Section E Penblewin to Canaston Bridge 52 6.1.6 Section F Canaston Bridge to Slebech Park 63 6.1.7 Section G Slebech Park to Deep Lake Farm 64 6.1.8 Section H Deep Lake Farm to Haverfordwest Golf Club 71 6.1.9 Section I Haverfordwest Golf Club to Scotchwell Roundabout 72 6.2 OVERTAKING 72 7 DO SOMETHING OPTION - DUAL CARRIAGEWAY STRATEGY 74 7.1 INTRODUCTION 74 7.1.1 Section A St Clears to Whitland Bypass 75 7.1.2 Section B Whitland Bypass 75 7.1.3 Section C Whitland Bypass to Llanddewi Velfrey 76 7.1.4 Section D Llanddewi Velfrey to Penblewin 77 7.1.5 Section E Penblewin to Canaston Bridge 81 7.1.6 Section F Canaston Bridge to Slebech Park 89 7.1.7 Section G Slebech Park to Deep Lake Farm 90 7.1.8 Section H Deep Lake Farm to Haverfordwest Golf Club 95 7.1.9 Section I Haverfordwest Golf Club to Scotchwell Roundabout 97 7.2 INITIAL JUNCTION PROPOSALS 99 7.2.1 Single Carriageway Junctions 100 7.2.2 Dual Carriageway Junctions 100 7.2.3 Access to Farm and Private Properties 100 8 TRAFFIC AND ACCIDENT ANALYSIS 101 8.1 GENERAL 101 8.2 TRAFFIC DATA 101 8.2.1 Existing Conditions (2002 data) 101 8.2.2 Accident Data 101 8.3 MODELLING AND VALIDATION 103 8.4 FORECASTING 103 8.5 CONGESTION REFERENCE FLOWS 104 8.6 EFFECTS OF SCHEME OPTIONS 105 8.6.1 Journey time savings 105 8.6.2 Journey Time Reliability 107 8.6.3 Accident Savings 107 8.7 CONCLUSIONS 107 9 ECONOMIC PERFORMANCE OF OPTIONS 109 9.1 INTRODUCTION 109 9.2 METHODS OF ANALYSIS 109 9.2.1 Application of COBA 109 9.3 INPUT DATA 109 9.3.1 Forecasting 109 H:\HHI\JOBS\43696 A40 St Clears to Fishguard\Reports\Options Report\ROR\ROR Vol1 Rev 10.doc December 2004 Page vii A40 WEST OF ST CLEARS ROUTE OPTIONS REPORT 9.3.2 QUADRO 109 9.3.3 Cost 109 9.4 OUTPUT DATA 110 9.4.1 COBA Results 110 9.4.2 Economics – COBA Analysis 111 9.5 NETWORK AND PRINTOUTS 111 9.6 DISCUSSION OF COBA RESULTS 111 9.6.1 NPV for options to be taken forward to the Technical Appraisal Report. 111 9.6.2 The valuation of accidents. 112 9.6.3 Valuation of accidents on links. 112 9.6.4 Valuation of accidents at junctions. 112 9.6.5 Link transit costs and traffic delay at roundabouts 112 9.6.6 Sensitivity testing 113 9.6.7 Programme and construction sequence 113 9.7 WIDER ECONOMIC ASSESSMENT 114 9.7.1 Introduction 114 9.7.2 Key Objectives 114 9.7.3 Key Conclusions 114 10 ENVIRONMENTAL CONSIDERATIONS 116 10.1 GENERAL ENVIRONMENTAL SUMMARY 116 10.1.1 Single Carriageway 116 10.1.2 Dual Carriageway 118 10.2 ROUTE OPTION DEVELOPMENT 120 10.2.1 Constraints 120 10.2.2 Single Carriageway Option 121 10.2.3 Dual Carriageway Options 121 10.3 SUMMARY OF CONSULTATION WITH PUBLIC BODIES 121 10.3.1 Environmental Liaison Group 121 11 APPRAISAL OF OPTIONS 122 11.1 SUMMARY OF THE STAG APPRAISAL PROCESS TO DATE. 122 11.2 APPRAISAL OF OPTIONS 122 11.3 OPTIONS TO BE TAKEN FORWARD 125 11.4 DISCARDED OPTIONS 125 12 PROGRAMME 126 12.1 BASIS OF PROGRAMME 126 13 PROCUREMENT OPTIONS 127 13.1 CRITERIA 127 13.1.1 ICE 5th/6th/7th Edition Form of Contract. 127 13.1.2 Design and Build (D&B) 127 13.1.3 Early Contractor Involvement (ECI) 127 13.1.4 Private Finance Initiative (PFI/DBFO) 128 13.2 PROCUREMENT OPTION 128 14 SUMMARY 129 14.1 EXISTING TRUNK ROAD 129 14.2 OPTIONS CONSIDERED 129 H:\HHI\JOBS\43696 A40 St Clears to Fishguard\Reports\Options Report\ROR\ROR Vol1 Rev 10.doc December 2004 Page viii A40 WEST OF ST CLEARS ROUTE OPTIONS REPORT 14.3 ROUTE OPTIONS REPORT 130 14.4 ENVIRONMENTAL APPRAISAL 130 14.5 TRAFFIC FLOWS AND ACCIDENTS 130 14.6 ECONOMIC ANALYSIS 131 14.6.1 COBA and QUADRO Analysis 131 14.6.2 Wider economic assessment 131 14.7 STAG APPRAISAL 131 14.8 ROUTES TO BE CONSIDERED FOR TAKING FORWARD TO THE TECHNICAL APPRAISAL REPORT (TAR) 131 14.8.1 Option Appraisal 131 14.8.2 Access to Farm and Private Properties 132 14.8.3 Procurement Option 133 15 CONCLUSIONS 134 TABLES FROM TEXT 137 TABLE 4.1 SINGLE CARRIAGEWAY EARTHWORKS 139 TABLE 4.2 DUAL CARRIAGEWAY EARTHWORKS 143 TABLE 5.1 SINGLE CARRIAGEWAY OPTIONS 147 TABLE 5.2 DUAL CARRIAGEWAY OPTIONS 153 TABLE 8.8 SINGLE CARRIAGEWAY OPTIONS ACCIDENT SAVINGS 159 TABLE 8.9 DUAL CARRIAGEWAY OPTIONS ACCIDENT SAVING S 163 TABLE 9.1 SINGLE CARRIAGEWAY OPTIONS COSTS AND NPV 167 TABLE 9.2 DUAL CARRIAGEWAY OPTIONS COSTS AND NPV 171 TABLE 11.3 SINGLE CARRIAGEWAY OPTIONS DISCARDED 175 TABLE 11.4 DUAL CARRIAGEWAY OPTIONS DISCARDED 179 TABLE 12.1 CONSTRUCTION PERIODS DUAL CARRIAGEWAY 183 TABLE 12.2 CONSTRUCTION PERIODS DUAL CARRIAGEWAY 185 APPENDICES 187 APPENDIX A – OBJECTIVES 189 APPENDIX B -- AST 1 FORMS 193 APPENDIX C – DETAILED COST ESTIMATES 207 SCHEDULE OF ESTIMATING RATES 209 STRUCTURES SUMMARY 213 SINGLE CARRIAGEWAY OPTIONS 219 DUAL CARRIAGEWAY OPTIONS 261 APPENDIX D – ENGINEERING DATA 295 DO MINIMUM 299 SINGLE CARRIAGEWAY 304 DUAL CARRIAGEWAY 309 APPENDIX E – AST2 SHEETS 315 APPENDIX F – OPTIONS MATRICES 317 H:\HHI\JOBS\43696 A40 St Clears to Fishguard\Reports\Options Report\ROR\ROR Vol1 Rev 10.doc December 2004 Page