M25 M26 Connectivity 21/06/2016 Reference number 103712

ECONOMIC CASE STUDY

FINAL REPORT

M25 M26 CONNECTIVITY ECONOMIC CASE STUDY

IDENTIFICATION TABLE Client/Project Kent County Council owner Project M25 M26 Connectivity

Study Economic Case Study

Type of document Final Report

Date 21/06/2016

File name M25M26 Report 2c (final).docx

Reference number 103712

Number of pages 83

APPROVAL

Version Name Date Modifications Ian Wilkinson, Author 07/04/2016 John Stephens Ian Wilkinson, 1 Checked by 07/04/2016 Version 1 Draft for client David Carter consideration Approved David Carter 07/04/2016 by Ian Wilkinson, Version 2 Report including client Author John Stephens, 21/06/2016 feedback: incorporating minor expansion on reporting of scheme David Carter costs, wider consideration of Ian Wilkinson, GIF/SHMA issues and dependent Checked by 21/06/2016 David Carter housing case, as well as minor 2c drafting points Version 2a/b including a few further snagging corrections and other minor Approved changes David Carter 21/06/2016 by Version 2c incorporating final comments from KCC and the study working group

TABLE OF CONTENTS

SUMMARY 6

BACKGROUND AND EXISTING STUDIES 6

HIGHWAY MODEL REVIEW 6

HIGHWAY OUTCOMES 7

WIDER ECONOMIC BENEFITS 10

OVERALL VALUE FOR MONEY CASE 10

LOCAL STAKEHOLDER CONSULTATION 11

CONCLUSIONS 12

1. INTRODUCTION 14

1.1 OVERVIEW 14

1.2 BACKGROUND PROVIDED BY KENT COUNTY COUNCIL (WITH SOME MINOR ADAPTATION) 15

1.3 DATA PROVISION 18

2. QUALITATIVE REVIEW 22

2.1 POLICY CONTEXT 22

2.2 ECONOMIC/VALUE FOR MONEY CASE AND WIDER BUSINESS CASE DELIVERY 23

3. HIGHWAY MODEL REVIEW 26

3.1 INTRODUCTION AND MODEL ROBUSTNESS 26

3.2 HIGHWAY MODEL REVIEW AND ACTIONS 26

3.3 HIGHWAY MODEL VALIDATION 30

4. ECONOMIC APPRAISAL 33

4.1 INTRODUCTION 33

4.2 HIGHWAY MODEL RESULTS AND INTERPRETATION 34

4.3 ECONOMIC ‘TUBA’ APPRAISAL 35

4.4 OUTCOMES OF HIGHWAY MODEL ACTIONS 36

4.5 SCHEME IMPACT OF OPTION 1A – JUNCTION 5 EAST-FACING SLIPS 38

4.6 SCHEME IMPACT OF OPTION 2C – A225 OTFORD SLIPS 41

4.7 FURTHER ANALYSIS OF OPTION 1A AND 2C 41

4.8 OUTCOMES OF HIGHWAY MODEL AND TUBA SENSITIVITY TESTS 46

4.9 ECONOMIC ANALYSIS OF OPTION 2C 47

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4.10 QUANTIFICATION AND MONETISATION OF OTHER BENEFITS 47

5. WIDER ECONOMIC BENEFITS 52

5.1 INTRODUCTION 52

5.2 LAND USE BENEFITS FROM RESIDENTIAL DEVELOPMENT 52

6. OVERALL VALUE FOR MONEY CASE 69

6.1 WEBTAG APPRAISAL TABLE 69

7. LOCAL STAKEHOLDER CONSULTATION 72

7.1 BACKGROUND 72

7.2 KEY FINDINGS 73

7.3 GENERAL COMMENTS 75

7.4 SUMMARY 75

8. CONCLUSIONS 72

APPENDIX A: ANALYSIS OF LABOUR MARKET INTEGRATION 79 APPENDIX B: TEE, PUBLIC ACCOUNTS AND AMCB TABLES 82

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LIST OF FIGURES

Figure 1. Flow Difference Due to Option 1A (2031 PM) (Full Model) 38 Figure 2. Flow Difference Due to Option 1A (2031 PM) (Zoomed) 39 Figure 3. Flow Difference Due to Option 1A (2031 PM) (Google Image) 39 Figure 4. Flow Difference Due to Option 1A (2031 PM) (Indicative Diagram of Key Impacts) 40 Figure 5. Flow Difference Due to Option 2C (2031 PM) (Zoomed) 41 Figure 6. Delay per Vehicle (seconds) Difference Due to Option 1A (2031 PM) (Zoomed) 43 Figure 7. Sector System 45 Figure 8. Sector based analysis of change in travel time Option 1A (2031 PM) (seconds) 45 Figure 9. WebTAG Appraisal Summary Table Template 69

LIST OF TABLES

Table 1. Condensed Appraisal Summary Table 11 Table 2. PB 2009 Study - Summary of Economic Assessment of M25 Junction 5 – Option 1A 20 Table 3. PB 2009 Study - Qualitative Appraisal of Option 1A 21 Table 4. Qualitative Summary of Potential Benefits and Impacts – Initial Review 25 Table 5. Highway Model PM Peak Matrices Sizes and Growth 27 Table 6. Comparison of Observed and Model Vehicle Flow (PM Peak Hour) 31 Table 7. Comparison of Observed and Model Vehicle Speed (PM Peak Hour) 32 Table 8. Summary of AMCB Results – Model Improvement 37 Table 9. Change in Traffic Flow on A25 (2031 PM Peak) (ALL VEHICLES) 42 Table 10. Change in Traffic Flow on A25 (2031 PM Peak) (CARS) 42 Table 11. Change in Traffic Flow on A25 (2031 PM Peak) (HGVs) 42 Table 12. Change in Traffic Flow on A225 Otford Road (2031 PM Peak) 43 Table 13. Change in EASTBOUND Travel Time on A25 (2031 PM Peak) (SECONDS) 44 Table 14. Change in WESTBOUND Travel Time on A25 (2031 PM Peak) (SECONDS) 44 Table 15. Summary of AMCB Results – Sensitivity Tests 47 Table 16. Summary of AMCB Results – Option 2C 47 Table 17. Global Change in Travel Distance (2031) (Vehicle Kilometres) 48 Table 18. Global Change in Travel Time (Vehicle Hours) 48 Table 19. Change in Traffic Flow on A25 (2031 PM Peak) 49 Table 20. Change in Traffic Flow on A225 Otford Road (2031 PM Peak) (HGVs) 49 Table 21. Travel Time on A25 (2031 PM Peak) (SECONDS) 49 Table 22. Accident Assessment 51 Table 23. Actual less predicted trips, separate urban and rural variables 64 Table 24. Sum of actual less predicted trips relative to working age population 65 Table 25. Propensity to travel to London, Surrey and Rest of South East 66 Table 26. Analysis of travel to work data 68 Table 27. Appraisal Summary Table (Part 1) 70 Table 28. Appraisal Summary Table (Part 2) 71 Table 29. Responding Parish & Town Councils Consultees 72 Appendix Table A 1: occupations of residents 80 Appendix Table A 2: qualifications and earnings of residents 80 Appendix Table A 3: workplace earnings and employment structure 81

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SUMMARY This summary reports the main tasks and outcomes for each part of the study. The headings reflect the report chapters which themselves are related to the Tasks in the study tender documents and the technical proposal.

This study should be treated as confidential.

Background and Existing Studies Kent County Council (KCC), Tonbridge & Malling Borough Council (TMBC) and Kent Association of Local Councils (KALC) required the provision of consultancy services to establish whether a robust economic case can be made for new east facing slip roads at an appropriate location in the vicinity of Junction 5 of the M25/M26 to improve connectivity to West Kent and provide congestion relief and wider benefits. The previous study in 2009 by Parsons Brinckerhoff (PB) considered the potential economic benefits of improved transport connectivity by using a cut-out or cordoned version of the Highway Agency’s (now Highways England) M25 SATURN Highway Model and the Department for Transport’s (DfT) Transport User Benefit Analysis (TUBA) software to assess the economic case. This approach identified transport user benefits, largely time savings that could be valued, which when set alongside the scheme costs generated a monetised BCR (Benefit to Cost Ratio) of 2.23. The current study provides a detailed review and, where possible, an update of the elements of the earlier PB model and the associated economic TUBA assessment. We have also considered a number of further qualitative and quantitative analyses and undertaken an assessment of the potential wider economic benefits, including residential development benefits, direct employment benefits and the scope for greater labour market integration.

Highway Model Review In accordance with Department for Transport good practice, as set out in the WebTAG guidance, we have attempted to ensure the robustness of the transport model and economic analysis outputs. However, we need to acknowledge that the modelling tools available to us have their limitations, in part due to the age of the models, but more importantly due to their coverage which is limited in the area to the area west of the A21 and Sevenoaks. Our work has included detailed reviews and improvements of the cordoned (SATURN) highway network model with sensitivity tests where appropriate, including:  assignment parameters including values of time and fuel and model convergence;  accuracy of model flows and travel times;  inclusion of inter-peak and AM peak models;  realism of the routes and locations (origins and destinations) experiencing congestion.

The review of the underlying model identified a number of enhancements and corrections to the model, including improved model convergence, improved representation of time periods (expanding from PM peak only to other periods) and a small but significant correction to the representation of network distances. In addition to using the highway model with its pre-existing representation of the east-facing slip roads at the A21/M25/M26 intersection (Option 1A), we have coded a representation of slip roads at

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the A225 at Otford (Option 2C). This has allowed us to consider the potential differences in traffic impacts between the (strategic accesses) onto the A21 and the (more localised access) to the A225. As the underlying model does not cover the area to the west of the A21 we have not been able to quantify the potential traffic impacts of the option of east-facing slip roads near Westerham.

Highway Outcomes Following the review of the underlying model and resulting enhancements and corrections, the forecasting model and DfT TUBA software were used to estimate the transport benefits of the slip road options. The benefit estimates are primarily driven by the highway outcomes, with re-routeing of traffic and journey time savings generating key economic benefits.

At a headline level, the slip road options fill a broadly 18 miles gap in junctions for M26 users between M26 J2A at Wrotham and M25 J6 at Godstone, allowing eastbound access and westbound egress to and from the M26 around Sevenoaks. Essentially the slip roads provide strategic road access to the Sevenoaks areas from East Kent, and via Dover to mainland Europe, as well as local traffic to and from mid-Kent, both avoiding the use of the A25 east of Sevenoaks towards Borough Green and M26 J6 at Wrotham. Any transfer of traffic flows to the strategic motorway network will provide some local journey time, congestion and environmental benefits, with some nuanced impacts arising from each of the options considered.

Highway Outcomes (A21 slip roads, Option 1A)  some localised movements along the A25 between Borough Green and Sevenoaks and the A21/A225 in Riverhead transfer to the M26 to access west Kent providing localised congestion relief, primarily along the A25 but also on some of the local roads around Stone Street and west towards the A21/A225 junction.  some journeys from the Orpington area could be attracted to divert from routeings using M25 Junctions 3-4 and M20 Junction 1-3 to a route using M25 Junctions 4-5 and M26 by undertaking a u- turn movement at the M25/A21/A25 junction.  Potential for some localised disbenefits due to changes in traffic flows at the A21/A25 junction that may require localised mitigation works to reduce or eliminate any impacts.

Highway Outcomes (A225, Option 2C)  some localised movements along the A25 between Borough Green and the A225 at Bat & Ball transfer to the M26 providing localised congestion relief again, principally along the A25, with net reductions in traffic flows slightly higher east of Bat & Ball than in Option 1A due to easier access into Sevenoaks itself from the M26.

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 Potential for some localised traffic disbenefits due to changes in flows at the Bat & Ball junction that may require localised mitigation works to reduce or eliminate any impacts.

It is noted that there are a number of large land use and transport developments in the south- eastern quadrant of the M25 between the M23/Gatwick Airport and the Dartford Crossing, including the Lower Thames Crossing, the large Paramount Studios visitor attraction, the Dartford, Thames Gateway and Cobble freight/container terminals and possible Gatwick Airport expansion. Whilst all of these developments could influence future year traffic flows, an examination of traffic routeings for all suggest it is unlikely that any will be affected by the east-facing slip roads, either directly or through secondary or wider traffic flow changes. The proposed slip roads are centred on Sevenoaks and predominantly offer improved east to south routeings and vice versa, whereas the large developments and transport infrastructure proposals identified are to the west and north.

Economic Outcomes An indicative economic appraisal has been developed using an updated set of TUBA economic appraisal parameters with a number of sensitivity tests undertaken around key parameters where these can be varied, such as annualisation assumptions that translate single period forecasts from the transport models into annualised benefit estimates. The table below shows a summary of the economic analysis based on our revised forecasts of the traffic impacts of the scheme and on a simple price-base update of the scheme costs used to underpin the 2009 study (capital costs of ~£77m (assumed to be in 2008 prices)); the underlying costs have not been reviewed or revised during this study. However, we provide a sensitivity for a higher scheme cost for Option 1A at the A21 (+15% to represent a possible unit cost premium in addition to any price based change). For Option 2C at Otford we have used a simple assumption that the costs of the slip roads in this vicinity (as well as works to the A225 and potentially the Bat & Ball A25/A225 junction) would be half of the cost of the M26/A21 works which are likely to be far more complex. Further consideration of the scheme will require a detailed analysis of the construction costs, updating the Option 1A A21 costs and estimating costs for Option 2C at Otford and for any Westerham options. The table shows (for Option 1A) high and low benefit assumptions. The ‘high benefits’ include annualisation factors that assume a significant level of benefits will be experienced outside of the weekday peak periods. This is a reasonable assumption, given that the key re-routeing impacts and travel time savings will occur throughout the evening and at weekends. The ‘low benefits’ assume these are restricted to weekdays (in-line with the PB study) together with a 15% uplift on construction costs. The analysis also includes a calculation of potential economic savings as a result of accident reductions based on reduced travel distance in Option 1A in particular. The BCR with and without this impact is shown.

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Indicative Economic Appraisal Summary VALUE 2009 STUDY 2016 STUDY Scheme: Option 1A Option 1A Option 1A Option 2C Westerham High or Low Estimate of benefits Low Benefits High Benefits High Benefits or costs Higher Costs

Present Value of Benefits (PVB) 119 97 69 52 n/a (£m) Present Value of Costs (PVC) (£m) 53 58 67 29 n/a BCR 2.23 1.66 1.03 1.79 n/a BCR (including accident savings) n/a 1.76 1.13 1.79 n/a Price base 2002 2010 2010 2010 2010

Outcomes The appraisal shown in the table clearly identifies a significant reduction in the present value of the benefit stream for Option 1A, primarily due to the small but significant correction to the underlying network model used in the 2009 study which alone reduces the apparent scheme benefits by just under 30%. The Option 1A high benefit assumption generates a BCR of 1.76 which would represent ‘medium value for money’ according to DfT guidance before any wider economic or non-monetised benefits are considered. The low benefit assumption reduces the BCR to 1.13. The Option 2C analysis, which uses the high benefit assumptions generates a BCR of 1.79. This result is similar to Option 1A because although the construction cost based PVC is halved, the PVB is also approximately halved due the reduced traffic flow impacts, limited as noted above to primarily local traffic flows. The Westerham option could not be assessed due to the model coverage limitations.

Environmental Benefits In addition to the monetised transport benefits, primarily arising from travel time savings, there will be a number of environmental impacts of each of the scheme options. For all options these will consist of changes in traffic-related noise and emissions arising from alterations in routeings. The impacts will be primarily reductions in noise and emissions on the A25 between Wrotham and Sevenoaks for the Junction 5 and Otford slip-road options, driven by reductions in traffic flows arising from the scheme. In Borough Green changes in traffic flows are expected to be up to 250 vehicles per hour or 20% of the flow in 2031. The alternative routeings for freight are expected to reduce HGV flows through Borough Green by up to 25%, though goods vehicles only account for around 5% of all vehicles on this section of the A25. Whilst there will be local environmental benefits on the A25, some small localised adverse impacts will arise from use of the new slip-road infrastructure in the vicinity of the Chevening Estate (Junction 5 slips) or on the A225 between Otford and Bat & Ball (Otford slips). For the Chevening estate and the areas of Chipstead on Chevening Road the new traffic flows will be small relative to the nearby background Junction 5 traffic movements, with design and mitigation measures of new slip roads essential to reduce any specific localised impacts. For the Otford slip road options, there will be perceived increases in traffic flows on the A225 as road users access Sevenoaks via the M26 and A225 rather than via the A25. This increase, of around 15%, may result in a need for localised mitigation works to reduce or eliminate any traffic and environmental issues at or in the vicinity of the Bat & Ball junction.

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In addition to the primary noise and emission impacts, there will be an opportunity to deliver local severance and potential quality of life benefits between Seal and Borough Green through lower traffic flows, but also the opportunity to trade-off some travel time benefits with more active provision of improved pedestrian crossings, cycling and road safety interventions.

Wider Economic Benefits The study considered three sources of wider economic benefits, namely dependent housing, use of employment land / employment generation and improved labour market connectivity. Where a transport scheme enables housing development to take place that would not otherwise happen because of the impacts of the development on the transport network, the planning gain from such ‘dependent’ housing development can now be included in the wider economic appraisal. An analysis of the potential value of any significant ‘dependent’ development, for example of a large scale development of say 2,500 housing units, suggests that, providing a ‘dependency case’ can be made, then the value of these benefits could be around £70m (PV in 2010 prices). However, we understand that at present there is a scarcity of known major housing sites in the Sevenoaks, Tonbridge & Malling, Tunbridge Wells areas that could accommodate any significant development volumes. Given the lack of identified housing sites of any significant scale that are considered well enough developed to be eligible for a ‘dependency test’, we can conclude this source will not contribute any value to an appraisal of the east facing slips, at least at present. However, whilst there may be some sites that could be considered as ‘emerging’, these have no status beyond that of a ‘Call for Sites’ exercise, with local authorities such as Tonbridge & Malling undertaking an assessment, concurrent with this study, to examine whether the locations identified have any development potential based on their suitability, availability and achievability during the current Local Plan period. In due course, if such sites become available, and the scale or value of development is enhanced by the provision of the slip roads, then the potential magnitude of any planning gain could fundamentally change the value for money assessment of the slip road options. Similarly, the assessment of employment land did not establish any links between east facing slips and the scale or timing of development on any employment sites in Kent. There are possible wider benefits associated with better access to Biggin Hill Airport; development scenarios suggest these benefits could be worth between £4m and £8m (in 2010 prices). However, this development and the potential use of the Moorhouse/Redland Tile Works site for distribution and storage activities are subject to planning consents which are not dependent on access considerations. East facing slips would, however, make both locations more accessible to Kent residents, and would also mitigate any increase in goods traffic on the A25 that would follow should consent be granted for distribution development at the Moorhouse/Redland Tile Works site. Analysis of travel to work patterns and modelling to identify ‘missing’ work trips in the A25 corridor did not indicate that accessibility has much effect on where people go to for work. Rather, socio- economic characteristics and access to London by rail exert a much greater effect on work travel patterns, especially in the Sevenoaks area.

Overall Value for Money Case In addition to the economic analysis reported above this considered a set of additional quantitative indicators as recommended in WebTAG. Chapter 6 of the report includes the full appraisal table in the format recommended by the DfT including both qualitative and quantitative assessments.

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Condensed Appraisal Summary Table The table below is reduced version of the full appraisal showing key economic, environmental and social indicators, in qualitative form and with supporting quantitative evidence.

Table 1. Condensed Appraisal Summary Table Qualitative and Non-Monetary Quantitative Junction 5 Slips (Option 1A) A225 Otford (Option 2C) A233 Westerham

ECONOMIC

 Little or no expected benefit for  Slips provide good direct  Slips provide good direct access to Sevenoaks from the east Connectivity / Travel Time access to Sevenoaks, Maidstone access to Sevenoaks and employment opportunities.  Access to Biggin Hill / Oxted

Change in PM Peak Vehicle Hours  -118 -0.21%  -64 -0.11% ENVIRONMENTAL  Reduced traffic flows on A25  Reduced traffic flows on A25  Limited local noise and air Noise and Air Quality may improve local noise/ air may improve local noise/ air quality impacts expected on A25 quality east of Sevenoaks quality east of Sevenoaks Change in PM Peak Vehicle Flow on A25  -110 -7%  -105 -7% SOCIAL

 Potential benefits in Seal,  Potential benefits in Seal,  Limited local noise and air Borough Green on A25 Borough Green on A25 quality impacts expected on A25 Quality of Life  Very localised impacts  Local impacts possible on the  Local impacts possible in possible near to J5 affecting A225 Westerham Chevening and local area  Reduced local severance in  Reduced local severance in  Potential for increased Severance Seal, Borough Green on A25 Seal, Borough Green on A25 severance around Westerham  Likely decrease in vehicle-km  Likely decrease in vehicle-km = Limited impacts of vehicle-km Safety and Accidents on local road network on local road network across the road network Change in PM Peak Vehicle Kilometres  -1967 -0.07% = -16 0.00%

Local Stakeholder Consultation

In partnership with Kent County Council and the Kent Association of Local Councils (KALC) a round of stakeholder consultation was undertaken with all local Parish and Town Councils in the Sevenoaks, Tonbridge & Malling, Tunbridge Wells and Maidstone areas to understand the different perceptions of the proposed scheme. . KALC initiated the consultation sending out a letter and questionnaire in December 2015 and January 2016 with 13 council’s responding to the consultation, and through these contacts two responses were received from political parties. The consultation questions focused on the three specific areas:

1. Journeys that people would like to make, but do not because of the time / inconvenience the journey would involve; 2. Sites that could be developed or existing sites in the area, that have been hampered by a lack of access to the motorway network; and 3. Traffic congestion, network resilience, accessibility or safety issues for motorists, pedestrians and cyclists that could arise if there is a new motorway access to the M25 and M26. ‘

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While many of the responses received did not provide specific answers on a question by question basis, relevant comments received have been collated from the responses and summarised against each of the three questions stated in the consultation.

 Six Parish and Town Councils responses indicated general support for a new east facing slip;  A total of three consultees confirmed their opposition to a new east facing slip; and  Six responses neither confirmed support or opposition to a new east facing slip.

Conclusions

Our review of the transport and wider economic benefits for the east-facing slip roads suggests some changes in emphasis from the earlier study in 2009. The transport journey time case for either of the options considered using the transport model, is weaker than initially set out in the 2009 report, with only modest localised benefits being apparent from either option, as opposed to some on-line benefits to M26 motorway users apparent in the earlier appraisal. Based on current travel patterns, there will be some net congestion relief on the local road network, primarily on the A25, although flow changes will be modest relative to the wider congestion issues in and around Sevenoaks. The localised transport benefits will include modest environmental benefits through reduced traffic growth on the A25, although the opportunity to introduce improved pedestrian crossings and cycle facilities, itself a benefit, could erode some of these environmental benefits through impeding free-flow traffic on the core section of the A25 west of Borough Green. For Option 1A with slip roads at the A21, the economic value of the key transport benefit streams generate a present value of around £70-95m (PV 2010 prices) relative to the present value of the engineering cost of £50-65m (PV 2010 prices) depending on the movement of underlying costs since their initial development as part of the 2009 study [note these figures are present values discounted to 2010]. This modest performance reflects the fairly limited and local catchments for the east- facing slip roads and modest traffic flows arising. Both benefits and costs of Option 2C at Otford are expected to be lower, but generating a similar monetised benefit to cost ratio.

At present it has not be possible to undertake a similar monetised analysis for the Westerham option due to the coverage of the transport model. A detail enhancement of the model, to the west in particular, would enable a comparative assessment across all options, as well as moving towards a WebTAG compliant model that will be required to meet later scheme appraisals and funding approval requirements. In the shorter term some expansion of the existing model could be undertaken to monetise the transport benefits of the Westerham option, as well as testing other options such as Dunton Green and providing more detail of the transport impacts of the existing options considered to date.

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The additional network capacity will however provide the potential to support some development growth. The increasing emphasis on transport to facilitate additional housing and employment growth is helpful for supporting the case for investment with methodologies now becoming established to assessing the benefits. Our review of the case for development support has included dependent housing and commercial sites, direct employment impacts, and greater labour market integration. As there is a lack of identified housing sites of any significant scale that are considered well enough developed to be eligible for a ‘dependency test’, we can conclude that there are no dependent housing benefits associated with any of the slip road options, at least present. Other potential developments are far more modest, or for example, at Fort Halstead, in locations clearly not reliant on the east-facing slip roads. In due course new significant sites may become available, and if the scale or value of these development is enhanced by the provision of the slip roads, as assessed through a ‘dependency test’, then the value of the 'dependent' housing could fundamentally change the value for money assessment of the slip road options.

It is suggested that Sevenoaks and Tonbridge & Malling both carefully consider all potential major development sites emerging through the planning processes, examining in detail their impacts on the capacity of the transport network and the potential for new infrastructure to enable additional development quantum and densities, as well as earlier delivery programmes1. Through undertaking technical work on forecasting the transport impacts and potential land value uplifts, it may be possible to identify stronger development-led support for major infrastructure proposals than has been established for the east-facing slips based on current development expectations working their way through the planning system. In respect of employment land, there are few potential sites available and pressure exists to convert sites from employment to residential use to meet housing targets. Our assessment suggests that better access to the M26 would have little impact on the demand for employment land in Tonbridge & Malling or Sevenoaks. However, east-facing slips around Westerham could support larger scale development over the Kent county boundary at Biggin Hill and the Moorhouse/Redland Tile Works sites, both developments are, however, subject to planning consents being granted. Overall, there appears to be an economic case for investment in the east-facing slip roads, but this is relatively weak, and with some key risks around scheme costs. The case as it stands relies largely on monetised transport benefits arising from journey time savings and reductions in accidents, alongside some modest localised environmental and other amenity benefits for residents living in the A25 corridor. Due to the lack of any significant housing developments in the area, at least sufficiently developed in planning terms, the scale of any monetised wider economic benefits will be limited. The study has reported on an initial consultation with the relevant local authorities, suggesting a range of responses from guarded support to local opposition, with some awaiting indications of potential performance from this study. Further consultation is clearly required if the proposals are to be developed further, and we suggest this is done in a structured way through a consultation strategy, particularly given some apparent opposition to the proposals, especially for residents and landowners in locations immediately adjacent to the new slip road locations.

1 Additional in the sense that such development would not take place without the transport scheme.

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1. INTRODUCTION

1.1 Overview

1.1.1 Kent County Council (KCC), Tonbridge & Malling Borough Council (TMBC) and Kent Association of Local Councils (KALC) required the provision of consultancy services to establish how a robust economic case can be made for new east facing slips at an appropriate location in the vicinity of Junction 5 of the M25/M26.

1.1.2 The main outcomes to be gained from this high level economic study, as defined by KCC, are as follows:  to establish the economic benefits of the proposed schemes  to establish the amount of additional development and jobs which can be supported by the proposed schemes and their impact on GVA  to make clear the link between the Local Road Network issue and the Strategic Road Network solution  to identify issues and opportunities in delivering the proposed schemes  to recommend which of the connectivity options considered is likely to offer the strongest economic case.

1.1.3 The study included tasks specified by KCC which are reflected the chapters of this report. Task 1 - Review of existing studies is briefly described in Chapter 2: Qualitative Review. The previous studies provided have been reviewed and the key outcomes taken forward for consideration in this study. Previous model work and economic analysis has been used as the starting point for this study where possible and applicable. Task 2 - Qualitative review of scheme options taking account of previous studies, is also described in Chapter 2.

1.1.4 Chapter 3 Highway Model Review addresses Task 3 - Propose a way forward for the economic case by describing the reviews, actions undertaken and further recommendations for both the highway and economic models.

1.1.5 Chapter 4 Economic Appraisal addresses Task 4 - Quantify economic benefits and disbenefits and includes the outcomes of both the highway modelling and the subsequent economic appraisal. We have expanded our assessment here to include quantitative reporting of both Option 1A (Junction 5 east-facing slips at the A21, as considered in the previous studies) and new quantitative analysis for Option 2C (Otford slips).

1.1.6 The remaining chapters relate directly to the further tasks as follows:  Task 5 - Estimate wider economic benefits of the schemes (Chapter 5)  Task 6 - Overall Value for Money Case (Chapter 6)  Task 7 - Consult with Partners was partly covered in Task 5, however the KALC consultation with local stakeholders is described in Chapter 7.  Chapter 8 provides conclusions to the study as included in the summary

1.1.7 The study will be used for lobbying Government on their decision making process, so a proposed scheme can be considered as a priority in the Highways England (HE) Route

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Strategy for London Orbital and M23 to Gatwick1, and provide evidence to ensure that this scheme is identified for development work to feed into HE’s second Route Investment Strategy (RIS). The Department for Transport’s (DfT) Transport Analysis Guidance (WebTAG) and best practices have been followed on a proportionate basis.

1.2 Background provided by Kent County Council (with some adaptation and expansion)

1.2.1 The M26 (opened in 1980) was originally part of the M25 orbital motorway route in the old London Ringways Plan. The decision was made to bring the M25 orbital motorway closer to London, turning the M25 north at Junction 5 to complete the ring to the Dartford Crossing. This left the M26 as a link road to the M20. As a result, a new section of the M25 between Junctions 5 and 3 was constructed between 1984 and 1986. This northbound section of the M25 was essentially a continuation of the northbound A21 Sevenoaks By-Pass. The resulting alignment of the M25 is therefore such that traffic continuing on the M25 at Junction 5 uses slip roads to remain on the M25, with the main alignment leading into the M26 in an eastbound direction and into the A21 in a southbound direction.

1.2.2 The Government’s decision not to provide an all-movements junction at Junction 5 was apparently based on traffic needs with the assumption that any traffic needing to travel to destinations south of Sevenoaks would have left the motorway network at earlier junctions and used local roads. The practical effect of this has been increasingly high reliance and consequently high traffic flow impacting communities on the alternative road network, especially along A25.

1.2.3 Junction 5 is of major importance to the Strategic Road Network (SRN) as it links the A21, the M26 and the M25, and is a vital link to the national freight network. However, this junction offers limited functionality.

1.2.4 Freight and general traffic approaching westbound, from the Channel Ports via the M20 and the M26 to the Sevenoaks area, is unable to use the junction to join the A21. The traffic is forced to exit the motorway network prematurely at Junction 2(A) of the M26 and travel along the A25 (a strategic trunk route classified by Kent County Council). This ‘A’ road passes through numerous villages, including Riverhead, Sevenoaks Bat & Ball, Seal, Borough Green and St Mary Platt. The A25 route is often heavily congested, especially at the main junctions (e.g. Sevenoaks Bat & Ball) and during peak periods.

1.2.5 Equally, traffic from the Sevenoaks area (including Westerham) is unable to take the logical route direct on to the M25/M26 at Junction 5 when travelling east towards Maidstone. This leads to unnecessary traffic congestion in several villages on route to Sevenoaks, with freight and long-distance vehicles mixing with commuters, shoppers and local traffic.

1.2.6 Kent County Council (KCC) has stated its intention to lobby Government for east facing slips to relieve the pressure on county roads in its Local Transport Plan2 with support for the scheme stated in other key documents including Growth without Gridlock3 and South East Local Enterprise Partnership Strategic Economic Plan4. Kent County Council’s Freight Action Plan5 also identifies the impacts of freight movements in the local communities in Kent and whilst focused on some of the key headline concerns arising from the county’s role as the gateway to mainland Europe, it also notes that many rural

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businesses, distribution centres and other generators of freight put a strain on the local road network. Of specific relevance to this study are two objectives setting out the need to effectively manage freight traffic routeings to encourage journeys to remain on the Strategic Road Network for as long as possible, and noting the need to address problems caused by freight traffic on local communities (objectives 3 and 4, respectively).

1.2.7 A number of studies have been carried out to assess the feasibility of east facing slips both at the M25 Junction 5 and on the A225 in Otford. These studies are:

 Kent County Council M25/M26 East Facing Slip Roads: Scheme Identification Study (September 1990);  Mouchel 1991 Study and 1993 Stage 1 Scheme Assessment Report;  London Orbital Multi Modal Study (ORBIT) (2001);  Hyder Rapid Widening, Junction 5 Improvements – Stage 1 Report Volume 6 (April 2004); and  Parsons Brinckerhoff M25 Junction 5 Study into the Provision of East Facing Slip Roads (February 2009).

Route Strategy for London Orbital and M23 to Gatwick Evidence Report (April 2014)

1.2.8 The Highway Agency’s (now Highways England) Route Strategy6 for London Orbital and M23 to Gatwick formulates their future work programmes. Kent County Council has fed in the need for this scheme as part of the process. This Route Strategy has investigated the need for a full Junction 5 layout with respect to its operation and value for money. A summary of key observations from the Route Strategy is given below:

 The M25 from Junctions 5 to 6 has an average speed of about 50 mph, which in the clockwise direction is likely to be caused by a high merging flow from the M26 and the A21;  The network performance 2012/13 delay level at the M25 J5 ranks the top 10% vehicles hour delay7, thought it has been subsequently noted that the network delay at J5 has moved due to the impacts of a “Smart Motorway” between Junctions 5 and 7, with the impact of free-flow tolls at the Dartford Crossing on the network performance at Junction 5 unknown at the time drafting; and  The key opportunities and challenges at this junction with respect to social & environment, operation and capacity are:

 air quality issues near Sevenoaks;  congested junction, compounded in its original design, suffering from merging goods vehicles and no eastbound movements from the A21;  poor journey time reliability, high merging flow from the M26;  limited availability of technology to control traffic, despite congestion towards Junction 5

1.2.9 In December 2014, the Government announced in their Route Investment Strategy that east facing slips at Junction 5 of the M25/M26 was not a top priority scheme and no funding was allocated for its development or construction. Highways England confirmed, however, that they remain open to work with KCC, Tonbridge & Malling Borough Council and Sevenoaks District Council to investigate the economic feasibility of the scheme.

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The Proposed Schemes

East Facing Slips at Junction 5 of M25/M26 (Option 1A)

1.2.10 Hyder (2004) study concluded that a scheme to facilitate movements between the A21 and the M26 was the preferred option (East Facing Slips at Junction 5). A HE plan for a full M25/M26 junction (to facilitate movements between the A21 and M26) is shown in Appendix 2 and summarised below:

 A21 Northbound to M26 Eastbound - This link would diverge from the A21 northbound and pass through a tunnel under the A21. Further eastwards it would pass over the M26 carriageways on a bridge before joining the M26 west of the A224 London Road.  A21 Northbound to M25 Westbound - To accommodate the above, the existing slip road would be replaced by one with a greater radius.  M26 Westbound to A21 Southbound - This link would diverge from the M26 westbound carriageway east of junction 5, passing under the southernmost span of the Chevening Road Viaduct.

1.2.11 The 2004 Hyder study estimated a total cost for the Junction 5 (Option 1A) scheme of £67m at 2001 prices. Following an update of the costs to 2008 prices, the 2009 Parsons Brinckerhoff (PB) study8 provided a new estimate for the total scheme costs as £77.4m.

1.2.12 The study concluded that east facing slips at an appropriate location in the vicinity of Junction 5 on the M25/M26 will help relieve traffic pressure, environmental degradation and poor air quality standards in communities along the A25 corridor through villages including Borough Green, Ightham, Seal and Riverhead. This was found to be the case for Option 1A considered in the PB report. This improvement will also deliver economic benefits in terms of addressing congestion, increasing accessibility on key routes and supporting development in the area.

East Facing Slips on the M26 at the A225 near Otford (Option 2C)

1.2.13 A potential location for east facing slips in the vicinity of Junction 5 of the M25/M26 could be at the A225 near Otford.

East Facing Slips on the M25 at the A233 near Westerham:

1.2.14 A potential location for east facing slips in the vicinity of Junction 5 of the M25/M26 could be at the A233 near Westerham.

Environmental Issues and Opportunities

1.2.15 The A25 from Wrotham Heath to Chipstead is a strategic trunk route, which provides an alternative route for traffic travelling to the M26 (East) from the Tonbridge and Sevenoaks areas and the A21 (South). Most of the villages along the A25 between Wrotham Heath and Westerham have areas designated as Air Quality Management Areas (AQMAs),e.g. Westerham, Riverhead, Sevenoaks Bat & Ball, Seal, Borough Green and St Mary Platt.

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1.2.16 It is anticipated that the proposed east facing slips would remove traffic along the A25 route onto the M20, M26 and M25, which will help delivering significant environmental benefits (notably in terms of air quality and health, but also for noise and vibration, and amenity) to those villages on or close to the A25. The removal of freight from the A25 could also substantially improve road safety for pedestrians and other users.

1.2.17 The proposed scheme will help to improve network resilience and accommodate the increasing number of HGV movements from the A21 to the M26, on approach to the Channel Tunnel and Port of Dover.

1.2.18 A report produced by ‘J5-Slips.Org’9 believes that the following AQMAs within which traffic reduction could potentially be brought about by the proposed schemes are:

 Tonbridge & Malling BC - Borough Green, Tonbridge High Street and Wateringbury  Sevenoaks DC - Westerham, Riverhead, Sevenoaks Bat & Ball and Seal  Tunbridge Wells BC - A26 Corridor

1.2.19 However, the ‘J5-Slips.Org’ report also states that there are a small number of residential properties which could experience an increase in traffic flow on the nearby road (and therefore a potential increase in air pollution). The properties within 100m of the following roads require specific attention to evaluate any adverse impacts which could potentially arise as a consequence of the proposed scheme:

 M26 between Junction 2(A) (Wrotham Heath) and Junction 5  A21 through Chipstead, Sundridge and Hildenborough.  A25 through Westerham town, and possibly also Limpsfield and Oxted. It is not clear how the proposed schemes would affect traffic flows along the M25 and A25 between Junctions 5 and 6. Junction 5 and its proposed east facing slips, notably those dwellings on the bridge of Chevening Lane, Chipstead.

______

1 https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/364210/London_Orbital_and_M23_to_Gatwick.pdf 2 2 http://www.kent.gov.uk/about-the-council/strategies-and-policies/transport-and-highways-policies/local-transport-plan 3http://www.kent.gov.uk/about-the-council/strategies-and-policies/transport-and-highways-policies/growth-without-gridlock 4 http://www.southeastlep.com/resources 5 https://www.kent.gov.uk/__data/assets/pdf_file/0012/6105/Freight-action-plan.pdf 6 https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/364210/London_Orbital_and_M23_to_Gatwick.pdf 7 Vehicle Hours Delay is an estimate of the total travel time experienced by all road users over and above the expected theoretical free- flow travel time 8 Parsons Brinckerhoff M25 Junction 5 Study into the Provision of East Facing Slip Roads (February 2009) 9 J5-Slips.

1.3 Data Provision

1.3.1 The SATURN Highway Model used in for the 2009 PB Study was provided by KCC. This was a sub-area/cut-out from the Highways Agency’s 2004 M25 Model and included PM peak hour only models for the base year (2007) model and 2015, 2021 and 2031 forecast models. The forecast models included the ‘with Option 1A’ (Junction 5 east- facing slips) and ‘without’ scenarios. SYSTRA requested a zone plan from WSPPB in order to understand the areas covered by the model zones, however this was not available.

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1.3.2 Similarly, the associated TUBA economic appraisal run files were requested from WSPPB for review and use as the starting point in this study. However for reasons associated with the age of the previous study they could not be provided.

1.3.3 The reports provided for this study were:

 M25 Junction 5, Review into the Provision of East Facing Slip Roads, Parsons Brinckerhoff (PB) for Highways Agency, April 2009. This report was provided by WSPPB on Thursday 17 December 2015 superseding the earlier February version provided by Kent County Council. The full appendices were also provided on this date;  M25 Rapid Widening, Junction 5 Improvements, Stage 1 Report Volume 6, Highways Agency; and  Air Quality Impact Assessment for M25 J5 East Facing Slips Scoping Study. Dr Yasmin Vawda for J5-Slips.org, March 2014

Key outcomes of 2009 Study

Quantitative

1.3.4 Chapter 10 of the 2009 PB study was a quantitative economic analysis using the Department for Transport’s TUBA software was undertaken for the Junction 5 east facing slips (Option 1A). The benefit-to-cost ratio (BCR) was reported to be 2.23. Table 2 below shows the full monetary detail provided for the PB 2009 economic analysis.

Qualitative

1.3.5 Chapter 11 of the 2009 PB study was a detailed qualitative appraisal of impacts for Option 1A. The approach was based the Department for Transport’s appraisal process: New Approach to Appraisal (NATA).

1.3.6 Table 3 below shows the qualitative impacts of option 1A upon each of the NATA objectives. A full Appraisal Summary Table was not been completed at this stage of the review, instead an assessment was carried out in the spirit of WebTAG Unit 2.5. However to assist with using this assessment for the 2016 study the objective are arranged and presented in WebTAG Appraisal Summary Table format (see Chapter 6).

1.3.7 Each subsection under the 5 key objectives was qualitatively assessed and broadly scored based on the WebTAG scoring levels as outlined below:

 Beneficial;  Slight beneficial;  Neutral;  Slight adverse, and;  Adverse

1.3.8 The review of this appraisal provided a useful qualitative assessment for Option 1A, the east facing slip roads at Junction 5. In Chapter 2: Qualitative Review of this report we add a summarised qualitative appraisal of Option 2C (east-facing slip roads at Otford)

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and the A233 at Westerham east-facing slip roads, alongside a summarised version for Option 1A.

1.3.9 In Chapter 6: Overall Value for Money Case quantitative indicators are available from the highway modelling and economic appraisal modelling and so these are merged with the qualitative assessment accordingly.

Parsons Brinkerhof 2009 Study – Key Indicators

Table 2. PB 2009 Study - Summary of Economic Assessment of M25 Junction 5 – Option 1A

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Table 3. PB 2009 Study - Qualitative Appraisal of Option 1A ECONOMIC Junction 5 Slips (Option 1A) The cost benefit analysis undertaken by PB suggests that the scheme has a Benefit to Cost Ratio of 2.23. This suggests a very good rate of Public Accounts Beneficial return on the proposed central government funding. Transport Economic Business users serving local towns along the A25 are likely to benefit from less traffic on this road. Through traffic travelling between the Efficiency: Business Users & M26 and A21 would also benefit from a more efficient use of road classes. Business users would also benefit from reduced costs due to Beneficial Transport Providers lower travel delays. Transport Economic The proposal makes better use of the different roads classes in the area by removing through traffic from local roads onto the strategic road Beneficial Efficiency: Consumers network. This makes travelling more efficient and so contributes to lower travelling costs. Improved connectivity at M25 Junction 5 is likely to enable local towns to benefit from the improved access. Consequently, this could attract more businesses to the area, potentially creating more employment opportunities and improving the local economy. However, since Wider Wider Impacts Neutral Economic Impact only applies to identifiable ‘Regeneration Areas’ and since none are located in the locality then the impact is assessed to be neutral. ENVIRONMENTAL Junction 5 Slips (Option 1A) Following the implementation of Option 1A, it is expected that the volumes of traffic on the A25 would reduce. The A25 is a predominantly urban road through towns with some properties fronting onto the road. In comparison, the M26, the route to which traffic would divert to, Slight Noise and Air Quality does not run through built-up areas and it also has a high level of existing ambient noise. Therefore the additional noise level due to beneficial increased traffic on this route is not expected to affect a significant number of receptors. Furthermore the change in traffic flows is low so the net impact on the M26 is considered neutral. In general terms moving traffic from a slow moving road onto a faster free flowing road would be beneficial in terms of air quality and Neutral / Greenhouse gases greenhouse gas emissions. However, there are a number of Air Quality Management Areas (AQMA) in the Study area and given that the HA Slight is advised not to move any traffic into an AQMA, the impact on these sensitive areas must be reviewed as part of this assessment. adverse

M25 Junction 5 is located within an Area of Natural Beauty (AONB). The implementation of Option 1A would result in additional infrastructure construction in this sensitive area. An ancient woodland site is also located within the study area, at this stage the scheme Slight Landscape designs do not encroach into this sensitive area. However, further assessment of the potential impact on this area during and post adverse construction would need to be considered as part of a detailed environmental assessment in future phases of work. The M25 Junction 5 is located at some distance away from nearby towns; hence the presence of new slip roads is not expected to generate Slight Townscape any impacts. The resultant reduction in traffic volume along the A25 could, however, help restore the local characteristics of towns such as beneficial Chipstead. The proposed slip roads do not affect any known heritage sites, although it is recommended that this is monitored during the course of the Historic Environment Neutral construction. The proposal is not expected to impact on any known areas with wildlife value. However, further investigation should be undertaken at a later stage to ascertain that no protected species are likely to be affected by the scheme. In addition, it is a Government policy to protect the Biodiversity “best and most versatile land” as defined in PPS7. According to DEFRA’s Agricultural Land Classification, the land affected by the scheme is Neutral Grade 3b land which falls outside the grades defined as the most versatile agricultural land. Using grade 3b land is in line with national planning policy. Darent Valley, south of M25 Junction 5, is identified as a fluvial floodplain. However, there is no indication that the proposed slip roads Water Environment would exacerbate existing conditions. Likewise, it is not expected that the scheme would impact on ground water quality. However, this Neutral must be assessed in detail as part of any future work. SOCIAL Junction 5 Slips (Option 1A) The proposed slip roads are located at an existing motorway junction where pedestrian or cyclist movements are not permitted. Some Severance Neutral existing footbridges may, however, be affected during construction. Local residents along the A25 could benefit from reduced traffic level.

Accident statistics indicate that at the M25 / A21 / A25 junction there were 8 accidents in the 5 year period from January 2003 to December 2007, one of which was fatal. The proposed scheme could potentially reduce the amount of weaving at this junction and hence could Safety and Accidents Neutral improve safety. However a full accident and road safety audit would need to be completed as part of any future assessment to confirm this assessment. It is not expected that the proposed east facing slips would be heavily used by transport providers. However, buses on routes running along Reliability impact on Slight the A25 are likely to benefit from reduced traffic levels, which may result in improved patronage due to less traffic congestion. Private Commuting and Other users Beneficial vehicles also would benefit from improved journey reliability. The proposed improvements aim at improving journeys already being made by car. In this case, the provision of slips on the motorway Physical activity network where access by pedestrians and cyclist is not permitted makes it neither practical nor safe to make provision for pedestrians or Neutral cyclists. Slight Journey quality It could be expected that the proposed scheme would provide an improved journey experience by routing traffic onto a higher quality road. beneficial Option 1A aims at diverting through traffic away from local roads. It is not expected that drivers and passengers would be subject to any Security Neutral significant changes to the level security. Slight Access to services The scheme increases interchange options at the M25 Junction 5, thereby improving local access to the trunk road network. beneficial At present, in the event of traffic incidents along the A25 requiring partial closure, there are no alternative routes without convoluted Slight Option and non-use values diversions. The presence of east facing slip roads provides the option to divert traffic along the M26, reducing the impact on local accesses beneficial that may otherwise suffer during emergencies. Transport Interchange The scheme does not propose any changes to existing transport interchange. Neutral The proposal is expected to have a neutral impact on national policies. For regional policies, the Kent and Medway Structure Plan 2006 apply. The provision of east facing slips is likely to give rise to slight adverse effects on two policies: EN3 – Protecting and Enhancing Slight Land-Use Policy Countryside Character; and EN4 – Protecting AONB. Similar policies can also be found in the local policies, namely Sevenoaks District adverse Sustainable Community Action Plan 2007-2010. The M25 Junction 5 is located in an area within the AONB. M25 Junction 5 is located in both AQMA and AONB areas, implementing Option1A could therefore contravene government environmental Slight Other Government Policies objectives. As discussed above in section 11.2, Further analysis will be necessary as part of any future study to determine the extent to adverse which sensitive areas could be affected by the scheme.

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2. QUALITATIVE REVIEW

2.1 Policy Context

Kent Connectivity

2.1.1 A good transport network is vital for Kent’s residents and businesses to have:

 access to opportunities, goods and services;  to attract new companies into the County;  to stimulate economic growth and regeneration; and  meet the demand for increased housing.

2.1.2 The grounded view in KCC’s Growth without Gridlock maintains that, while car travel remains the only realistic option for many, a fully integrated high quality transport network is required to unlock these development opportunities for housing, services and regeneration.

2.1.3 Recent transport investment in Kent’s connectivity has seen the delivery of HS1, significantly reducing train journey times to the capital and, along with the introduction of the Fastrack BRT around Dartford, unlocking development potential in the Kent Thameside regeneration area of the Thames Gateway. Highway investment has improved A2/M25 access and the recently completed East Kent Access 2 has enhanced access to some of Kent’s most deprived areas in Thanet and Sandwich. While a long- term and resilient strategy is required to tackle Operation Stack, future investment in transport will focus on enabling the growth areas with improved M20 access at Maidstone and Ashford and supporting a second crossing at Dartford.

2.1.4 Kent has traditionally had excellent lateral connectivity between the M25 and sea ports, whereas north-south movement is hampered by congested infrastructure and slow journey times. The 2017 completion of the A21 Tonbridge to Pembury dualling scheme will start to address this imbalance and tackle peak time congestion, potentially unlocking latent development potential in the prosperous west Kent area and improving journey times to the south coast. The proposed A228 Colts Hill Strategic Link would also improve north-south movement for road traffic between Tunbridge Wells and Maidstone.

2.1.5 The proposals for east facing slips and an improved westbound slip at Junction 5 of the M25/M26 would strongly complement these wider west Kent schemes and tackle specific transport issues in and around Sevenoaks District including town centre air quality and congestion on the A25 and A225 corridors.

Unlocking Development

2.1.6 The emerging and adopted Core Strategies of the largely rural west Kent authorities demonstrate varying development trajectories over the next 20 years. Based on the Kent & Medway Growth and Infrastructure Framework (GIF2) document of September 2015, Sevenoaks District set out a relatively modest need for 3,300 - 3,600 houses, with

2 Aecom, September 2015

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Tunbridge Wells and Tonbridge & Malling Boroughs seeking to deliver 6,000 and 13,300 homes respectively.

2.1.7 Strategic Housing Market Assessments (SHMA) reported for Sevenoaks and Tunbridge Wells in September 20153 and for Tonbridge & Malling in June 20154 identify an objectively assessed need for additional housing units of 12,400 in Sevenoaks and 12,960 in Tunbridge Wells between 2013 and 2033, and 13,640 in Tonbridge & Malling between 2011 and 2031.

2.1.8 With these volumes of new housing identified, it has been suggested by KCC, as part of the exercise ‘selling’ the development potential in west Kent, that the Junction 5 scheme could either directly or indirectly contribute to the delivery of some of the 40,000 housing starts over the next 20 years in the west Kent and Maidstone areas. This is one of the key areas of our work in this study, as reported in detail in Chapter 5.

2.1.9 With a focus on redeveloping and rebalancing use on existing employment land, the strategy to deliver employment floor space in west Kent is designed to counter the area’s recent lag in economic growth within the South East region. Kent’s recent investment focus has been on larger regeneration initiatives at Kent Thameside and Ashford, with west Kent’s connectivity issues affecting journey times and public transport acknowledged to influence the retention and attraction of business. Moderate growth forecasts for the three west Kent authorities expect to see a net gain of approximately 40,000m2 of new commercial floorspace, however this includes uptake of approximately 175,000m2 of existing vacant floorspace. A key constraint identified in Tunbridge Wells Borough’s 2010 Employment Land Review included indirect access and slow journey times between the main employment centres and the motorway network.

2.1.10 It has been suggested by KCC that the Junction 5 scheme could assist with the connectivity of employment centres within the area, improve access to the motorway network and facilitate economic regeneration of significant vacant, pipeline and new commercial floorspace at key sites, such as Paddock Wood and Kings Hill, to reverse the trends of recent years. Again, this is one of the key areas of our work in this study, as reported in detail in Chapter 5.

2.2 Economic/Value for Money Case and Wider Business Case Delivery

2.2.1 Developing and delivering major transport schemes requires skills in a very wide range of technical disciplines, combined with a strong stakeholder and community engagement and a commitment of the promoters throughout the scheme gestation periods from feasibility through to detailed design and implementation. This study forms an important early part of the scheme development and has been undertaken with a wider appreciation and awareness of both strategic and tactical needs of scheme development.

2.2.2 Considering the economic case for the east-facing slip roads, in its widest sense, will need to include two-way feeds of strategic messages to/from the strategic case, developing readily articulated assessments to key stakeholders including elected

3 GL Hearn, SHMA Final Report, September 2015 4 GL Hearn, SHMA Update Report, June 2015

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members, lobby groups, potentially the general public, and crucially potential funding and delivery agencies through the South East Local Enterprise Partnership (LEP) and Highways England (HE).

2.2.3 At this stage of the scheme development, and within the agreed timescale, the study has focused on a higher level assessment than will be ultimately required in developing formal business cases for scheme funding; the immediate needs are to firmly establish the case for intervention that can be used to lobby Government, the LEP and HE to ensure the scheme is considered in the second round of the Road Investment Strategy programme (the first round of which included relatively little new or committed investment in Kent).

2.2.4 Our approach to this commission was focussed on undertaking and reporting on a robust high level review, informed by both technical work using existing tools (such as the transport model) combined with strong judgements, particularly in respect of the case for dependent housing to support the scheme economics.

2.2.5 There was need to leave positive legacies for future development, for example by not over-selling benefits or under-costing in any quantified assessment. The scheme options can deliver a range of real benefits to both the local communities in west Kent as well as strategical benefits to the motorway network, without the need to raise unrealistic expectations that will (by necessity) be revealed during later scrutiny through both planning and funding approvals processes.

2.2.6 Our early high level thoughts on the potential benefits and impacts of the options, based on discussions during the development of this proposal, are shown in Table 4; these and a wider range of indicators are developed further, quantified where appropriate, later in the report.

2.2.7 Highways England (HE) are likely to be the implementation body for any improvements. HE has a clearly defined and staged Project Control Framework (PCF). PCF stage 0 is ‘Strategy, shaping and prioritisation’ and stage 1 is ‘Option identification’. We therefore ensure that our analysis and reporting here is consistent with the early PCF requirements and that the initial versions of relevant PCF ‘products’ can readily use the information and data generated from the study in order to provide HE with a sound basis to support and commence scheme development.

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Table 4. Qualitative Summary of Potential Benefits and Impacts – Initial Review

JUNCTION 5 A225 OTFORD A233 WESTERHAM

Vehicle Flow -  Significant relief for A25  Partial relief for A25  Limited relief to A25 Wider Impacts  Access to A21 s/b for  Avoids additional direct journeys south of Sevenoaks pressure to J5 and A21

Vehicle Flow - = Traffic remains on the trunk  Implications for A225  Increased traffic flow via Local Impacts road network, except for Westerham accessing M25 access

Connectivity /  Slips provide good direct  Slips provide good direct  Little or no benefit for Travel Time access to Sevenoaks, access to Sevenoaks access to Sevenoaks from Maidstone and employment the east

opportunities.  Access to Biggin Hill / Oxted

Network  Improved motorway  Improved motorway  Improved motorway ECONOMIC Reliability and resilience, but local resilience, but local resilience, but local Resilience implications implications implications

Dependent  Greatest accessibility  Local accessibility impacts  Local accessibility Housing impact but support to new may provide support to new impacts may provide housing sites will be location location specific housing support to local sites and in specific sites Biggin Hill

Employment  Larger catchment area for  Larger catchment area for = Limited increases Support Maidstone area employers in Maidstone area employers employer access to workers accessing Sevenoaks workers in accessing Sevenoaks workers

Noise and Air  Reduced traffic flows on  Reduced traffic flows on  Limited local noise and air Quality A25 may improve local noise/ A25 may improve local quality impacts on A25

air quality east of Sevenoaks noise/air quality east of Sevenoaks

Climate  Reduced impacts due to  Reduced impacts due to = Limited impacts due to Change decrease in vehicle-km decrease in vehicle-km changes in vehicle-km

ENVIRONMENTAL Landscape =/ Impacts depend on  Impacts depend on design  Impacts depend on design. Existing multi-level design junction

Quality of Life  Potential benefits in Seal,  Potential benefits in Seal,  Limited local noise and air Borough Green on A25 Borough Green on A25 quality impacts on A25  Local impacts possible on  Local impacts possible in the A225 Westerham

Severance  Reduced local severance in  Reduced local severance  Potential for increased Seal, Borough Green on A25 in Seal, Borough Green on severance around SOCIAL A25 Westerham

Safety  Likely decrease in vehicle-  Likely decrease in vehicle- =? Limited impacts of km on local road network km on local road network vehicle-km across the road network

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3. HIGHWAY MODEL REVIEW

3.1 Introduction and Model Robustness

3.1.1 In accordance with good practice we have taken steps to ensure the reliability of the transport model and economic analysis outputs. These include detailed reviews of the (SATURN) highway network model with sensitivity tests where appropriate, including:

 assignment parameters including values of time and fuel and model convergence;  accuracy of model flows and travel times (model validation);  inclusion of simple inter-peak and AM peak models;  realism of the routes and locations (origins and destinations) experiencing congestion and benefitting from the new Junction 5 slips.

The highway model reviews and actions are described in this Chapter.

3.1.2 A similarly diligent approach has been taken to the economic analysis which uses the DfT’s TUBA (Transport User Benefit Analysis) software. We have undertaken several reviews and sensitivity tests including:

 TUBA parameter review;  annualisation assumptions;  inclusion of simple inter-peak and AM peak models.

The economic analysis work is described in Chapter 4.

3.2 Highway Model Review and Actions

3.2.1 The comprehensive model review identified some aspects of the highway modelling which required actions and/or recommendations in further work. These are described below from paragraph 3.2.5 onwards.

3.2.2 The impact of the actions undertaken on the economic appraisal are described in Chapter 4.

3.2.3 This section contains some modelling terminology, it is however important to document this process in order to demonstrate, robust and WebTAG compliant procedures and checks are being undertaken.

Model Testing

3.2.4 On receipt of the existing model used in the 2009 Study the model files were tested. This was particularly important given that the model is seven years old. The main action required was correction of a matrix-network mismatch in the number of zones. This was due to a network connectivity issue resulting in zones 61105, 61123, 61127, 61185 being missing in network.

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Value of Time and Fuel Costs

3.2.5 These were reviewed and updates were made to current WebTAG recommendations. In the highway model these are coded by vehicle class as pence per minute (PPM) and pence per kilometre (PPK) and ensure that relative considerations of journey time and distance are realistically represented to ensure realistic route choices.

Convergence

3.2.6 Highway models work iteratively to balance the costs between the numerous route choices available for a particular origin-destination journey.

3.2.7 The model convergence is critical to robust model performance. The assignment was forced to terminate after 120 simulation loops (SATURN parameter MASL=120). The maximum number of assignment loops has been increased to 300 to ensure better convergence.

Model Dimensions: Periods and User Classes

Limitations and Implications

3.2.8 The 2009 model is a PM only and includes two user classes: car and goods, the matrices sizes are as follows:

Table 5. Highway Model PM Peak Matrices Sizes and Growth Number of trips Growth 2007 2015 2021 2031 2007-15 2015-21 2021-31 No. Zones 229 233 233 233 UC1 120,427 129,796 135,697 142,836 7.8% 4.5% 5.3% UC2 13,517 13,993 14,331 14,809 3.5% 2.4% 3.3% Total 133,945 143,789 150,028 157,645 7.3% 4.3% 5.1% 3.2.9 The 2009 Study economic analysis was reliant on the PM peak conditions only. This will lead to misleading conclusions on the locations of users experiencing benefits and also the scale of the benefits. There could be conditions in the AM peak and inter-peak that are overlooked and these are likely to be at different locations to the PM peak, particularly given the tidality of peak hour traffic in the area.

3.2.10 The model correctly predicts congested conditions in parts of the network that could be relieved by the Junction 5 slips scheme. As this congestion is likely to be lower in other periods it is possible that reliance on the PM peak could over-estimate benefits when used to estimate over a full day.

3.2.11 The future year growth estimates for years up to 2031 were as estimated by the 2009 study. Future growth within the model would be expected to have comprised of general growth (arising from growth in economic activity in general) and specific interventions (development or transport interventions). It is not known which specific developments

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have been included or not in the 2009 model forecasts (implicitly or explicitly) nor how these related to general background demand growth. The potential specific developments, mostly uncommitted at present, include the Lower Thames Crossing, the large Paramount Studios visitor attraction, the Dartford, Thames Gateway and Cobble freight/container terminals and possible Gatwick Airport expansion.

3.2.12 Whilst all of these developments could influence future year traffic flows in the south- eastern quadrant of the M25 between the M23, Gatwick Airport and the Dartford Crossing, an examination of traffic routeings for all suggest it is unlikely that any will be affected by the east-facing slip roads, either directly or through secondary or wider traffic flow changes.

Recommended Actions in Future Work

3.2.13 Consideration should be given to upgrading the model to include an AM peak hour and an inter-peak hour, which would be required for DfT WebTAG compliance.

3.2.14 An initial AM matrix could be generated by transposing the PM with checks or refinement using Census Journey to Work and traffic counts. The inter-peak could use a combination of AM and PM travel patterns adjusted to appropriate traffic volumes. This would not be fully DfT WebTAG compliant but preferable to basing economic/TUBA analysis on a PM peak only. This view is broadly consistent with the recommendations in the PB study (para 1.9.6), beyond current budget but required in due course for a compliant business case as this develops more formally.

3.2.15 Models are usually developed with four user classes, plus a taxi user class in London models. These are:  Car Private Use (eg commuting)  Car Business Use  Light Goods Vehicle (LGV)  Heavy Good Vehicle (HGV)

3.2.16 For economic analysis in particular the different values of time and fuel costs for these user classes would provide a more accurate outcome in terms of travel time and cost changes resulting from the scheme. Consideration should be given to upgrading the model to include these user classes in due course.

Action Taken in this Study

3.2.17 In order to work towards addition of the detail required, but also to provide more confidence in model outcomes we have used a very simple procedure to create inter- peak and AM peak matrices for use in the SATURN model and economic (TUBA) analysis.

3.2.18 Inclusion of a less congested inter-peak model additionally provides a useful check of less congested traffic conditions and network routing patterns, which increases understanding and confidence in the model.

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Scheme Coding

3.2.19 Some corrections were undertaken to distances and speeds which had resulted in inconsistency between the ‘with’ and ‘without’ scheme models. This included an inappropriate change in the distance of the westbound M26 approach to Junction 5 which resulted in a significant inappropriate benefit due to the large traffic flow on the motorway.

Model Coverage

Limitations

3.2.20 There are some concerns regarding the coverage of the model to the west. The model area was extracted from the M25 Model (Highways England). It is considered that the model was cut too abruptly on western edge excluding key areas such as Westerham, Biggin Hill and M25 Junction 6. Implications

3.2.21 The restricted coverage could be limiting the accuracy and/or scale of potential benefits such as for travel times and congestion delay. In terms of scale of benefits it is most likely that these will be underestimated because journeys to/from the west are being prevented from potentially rerouting to take advantage of the scheme. There are some travel time benefits being experienced close to the western edge of the model and so if the model was extended these benefits could extend to areas where the impact is currently excluded from the analysis.

3.2.22 The lack of model coverage west of the A21 is a technical concern, but also one in terms of perception of fairness of treatment of options, particularly as it is not be possible to test the Westerham option at all using the current model.

Recommended Actions in Future Work

3.2.23 In order to work towards a WebTAG compliant model some detail enhancement to the west in particular will be of value. This would be to an area covered in detail by Transport for London’s South London Highway Assignment Model and making use of this could be considered. However, in the shorter term some treatment of the existing model at relatively low cost could be undertaken making use of Census Outputs Areas and Journey to Work to disaggregate zones.

3.2.24 Enhancement to the west will be of value for all options, particularly as the model predicts benefits are experienced for journeys towards south-east London and it is acknowledged that Biggin Hill and Biggin Hill Airport will be affected by the proposed schemes.

3.2.25 Given the age of the M25 Model revisiting this to extend the area westward towards Westerham would not be recommended.

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Further Option Testing

Limitations

3.2.26 The current scope of this study has been to include only the Junction 5 east facing slips option in the quantitative economic analysis. The options considered at Otford and Westerham are considered only at a qualitative level, guided by the quantitative outcomes for the Junction 5 scheme.

Implications

3.2.27 In addition to being unable to make direct quantitative comparison between the schemes, not testing other options in the model has some implications for providing confidence in model realism. Testing of an alternative option(s) would provide increased confidence in the model’s ability to realistically simulate the outcomes of differences between the schemes, some of which will quite subtle. The Otford option will probably achieve similar outcomes to Junction 5 slips for many journeys, however the local impacts at Riverhead and Bat and Ball will be different and it will be useful to see the impact of this.

Recommended Actions in Future Work

3.2.28 Full testing of the other options (Otford, Westerham and possibly Dunton Green) in the model alongside the Junction 5 slips, rather than making qualitative assessment, would not be too onerous and more logical, in order to make a fair comparison and this could include both Otford and Dunton Green options to illustrate that we have really covered all options. As noted elsewhere, in the short-term we are not able test the Westerham option due to the current model’s western coverage problem.

Action Taken in this Study

3.2.29 As it also increases confidence in the model we have undertaken testing of the Otford slips enabling some traffic flow and economic comparison of the schemes. For full economics a construction cost of half of the Option 1A cost is assumed, however given the uncertainty of this the focus of outcomes and comparison with other options would be on the traffic flows/delays and economic benefits rather than the ratio of benefits to cost.

3.3 Highway Model Validation

3.3.1 An exercise was undertaken to check the model’s 2015 ‘forecast’ year against actual 2015 traffic flows and speeds. The highway model base year is 2007 so although 2015 is in the past in terms of the function of the model it remains effectively a forecast year.

3.3.2 The observed flow and travel time information is provided by Highways England from their online databases.

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Traffic Flow Validation

3.3.3 Table 6 shows a comparison major road observed and modelled vehicles flows. In most instances the flows are broadly in-line which each other and therefore the model is regarded as suitably realistic for the purposes of this study.

Table 6. Comparison of Observed and Model Vehicle Flow (PM Peak Hour) Observed Link Length Model Flow Road Dir Flow % Diff (km) (Vehicles) (Vehicles) A21 between A225 and M25 NB 7.22 1,612 1,611 0% M25 between A21 and M25 J5 NB 1.22 1,948 1,700 -13% M25 between M25 J5 and A21 SB 0.84 1,690 2,108 25% A21 between M25 and A225 SB 7.22 2,049 2,205 8% A2 between A2018 and M25 J2 EB 4.32 5,266 5,004 -5% A2 between M25 J2 and A296 EB 2.95 5,983 5,557 -7% A2 between A227 and M2 J1 EB 6.57 6,514 4,476 -31% M2 between M2 J1 and M2 J2 EB 3.08 5,024 3,582 -29% M2 between M2 J2 and M2 J3 EB 5.97 4,928 4,456 -10% M2 between M2 J3 and M2 J4 EB 6.56 4,007 3,590 -10% M2 between M2 J4 and M2 J3 WB 6.56 2,666 2,652 -1% M2 between M2 J3 and M2 J2 WB 5.97 3,440 3,816 11% M2 between M2 J2 and M2 J1 WB 2.78 3,555 3,102 -13% A2 between M2 J1 and A227 WB 6.47 4,442 3,544 -20% A2 between A296 and M25 J2 WB 1.85 4,469 3,801 -15% A2 between M25 J2 and A2018 WB 5.75 3,893 3,064 -21% M20 between M20 J1 and M20 J2 EB 12.18 3,179 2,613 -18% M20 between M20 J2 and M20 J3 EB 4.22 2,529 2,542 1% M20 between M20 J3 and M20 J4 EB 5.74 5,122 5,439 6% M20 between M20 J4 and M20 J5 EB 5.38 5,593 5,267 -6% M20 between M20 J5 and M20 J6 EB 2.94 4,816 4,659 -3% M20 between M20 J6 and M20 J7 EB 2.21 5,536 5,009 -10% M20 between M20 J7 and M20 J8 EB 6.40 3,523 3,258 -8% M20 between M20 J8 and M20 J7 WB 5.90 2,785 3,438 23% M20 between M20 J7 and M20 J6 WB 2.21 3,927 4,259 8% M20 between M20 J6 and M20 J5 WB 2.82 4,139 3,850 -7% M20 between M20 J5 and M20 J4 WB 4.60 3,907 3,018 -23% M20 between M20 J4 and M20 J3 WB 5.45 2,998 2,664 -11% M20 between M20 J3 and M20 J2 WB 3.53 1,341 2,035 52% M20 between M20 J2 and M20 J1 WB 13.69 1,654 1,438 -13% M25 between M25 J2 and M25 J3 CW 5.10 4,651 4,484 -4% M25 between M25 J3 and M25 J4 CW 5.49 3,704 3,581 -3% M25 between M25 J4 and M25 J5 CW 7.74 3,260 2,943 -10% M25 between M25 J5 and M25 J4 AC 6.64 3,662 3,032 -17% M25 between M25 J4 and M25 J3 AC 6.19 4,220 3,640 -14% M25 between M25 J3 and M25 J2 AC 5.07 4,209 4,334 3% M26 between M25 J5 and M26 J2A EB 14.21 2,177 1,781 -18% M26 between M26 J2A and M25 J5 WB 14.55 1,230 1,700 38%

Speed Validation

3.3.4 Table 7 shows a comparison major road observed and modelled vehicle congested speeds. In most instances the speeds are consistent each other and therefore the model is regarded as suitably realistic for the purposes of this study.

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Table 7. Comparison of Observed and Model Vehicle Speed (PM Peak Hour)

Link Length HE Speed Model Speed Road Dir % Diff (km) (kph) (kph)

A21 between A225 and M25 NB 7.22 103 92 -10% M25 between A21 and M25 J5 NB 1.22 97 95 -2% M25 between M25 J5 and A21 SB 0.84 98 91 -7% A21 between M25 and A225 SB 7.22 101 89 -12% A2 between A2018 and M25 J2 EB 4.32 65 65 0% A2 between M25 J2 and A296 EB 2.95 74 36 -51% A2 between A227 and M2 J1 EB 6.57 92 64 -30% M2 between M2 J1 and M2 J2 EB 3.08 98 97 -1% M2 between M2 J2 and M2 J3 EB 5.97 91 90 -2% M2 between M2 J3 and M2 J4 EB 6.56 98 98 0% M2 between M2 J4 and M2 J3 WB 6.56 105 105 0% M2 between M2 J3 and M2 J2 WB 5.97 110 95 -13% M2 between M2 J2 and M2 J1 WB 2.78 104 103 -1% A2 between M2 J1 and A227 WB 6.47 103 88 -14% A2 between A296 and M25 J2 WB 1.85 97 86 -11% A2 between M25 J2 and A2018 WB 5.75 93 89 -5% M20 between M20 J1 and M20 J2 EB 12.18 93 100 8% M20 between M20 J2 and M20 J3 EB 4.22 107 104 -3% M20 between M20 J3 and M20 J4 EB 5.74 54 49 -10% M20 between M20 J4 and M20 J5 EB 5.38 66 56 -14% M20 between M20 J5 and M20 J6 EB 2.94 83 83 0% M20 between M20 J6 and M20 J7 EB 2.21 84 67 -20% M20 between M20 J7 and M20 J8 EB 6.40 104 97 -6% M20 between M20 J8 and M20 J7 WB 5.90 104 97 -6% M20 between M20 J7 and M20 J6 WB 2.21 98 93 -5% M20 between M20 J6 and M20 J5 WB 2.82 100 99 -1% M20 between M20 J5 and M20 J4 WB 4.60 99 79 -20% M20 between M20 J4 and M20 J3 WB 5.45 103 95 -7% M20 between M20 J3 and M20 J2 WB 3.53 107 106 0% M20 between M20 J2 and M20 J1 WB 13.69 118 109 -7% M25 between M25 J2 and M25 J3 CW 5.10 101 72 -29% M25 between M25 J3 and M25 J4 CW 5.49 105 99 -6% M25 between M25 J4 and M25 J5 CW 7.74 105 100 -5% M25 between M25 J5 and M25 J4 AC 6.64 99 99 1% M25 between M25 J4 and M25 J3 AC 6.19 79 97 22% M25 between M25 J3 and M25 J2 AC 5.07 46 81 75% M26 between M25 J5 and M26 J2A EB 14.21 72 98 37% M26 between M26 J2A and M25 J5 WB 14.55 105 86 -18%

Model Validation Conclusions

3.3.5 It is concluded that for the purposes of this study the highway model provides a realistic enough reflection of current traffic conditions on the network, in terms of both traffic volumes and travel speeds and times.

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4. ECONOMIC APPRAISAL

4.1 Introduction

4.1.1 This Chapter reports the main quantitative and monetary outcomes of this study through use of the SATURN highway and the TUBA economic appraisal, the main quantitative tools available for this (or any) major highway scheme.

4.1.2 The Department for Transport provides useful advice on value for money assessment of transport schemes. The full document can be found at the following link: https://www.gov.uk/government/publications/value-for-money-advice-for-local- transport-decision-makers

4.1.3 At this stage the document provides useful guidance on the considerations to be included in the quantitative and qualitative assessments, providing an overview of the Value for Money process including advice on the different stages of the assessment and how these contribute to the final Value for Money statement.

4.1.4 Whilst this advice note does provide some advice on the development of the Initial BCR, the main focus of this document is outlining the Value for Money assessment process and providing detail on the impacts that contribute to the BCR. This note should therefore be seen as complementary to, and be used in conjunction with, WebTAG.

4.1.5 A key consideration when applying both the advice in this note and WebTAG guidance is the need for proportionality. The scale and severity of the impacts of the scheme and the uncertainty in assessment should define the level of effort needed for each element of the assessment.

4.1.6 The advice provided on the monetisation of quantitative and qualitative information for the BCR reflects best practice in the DfT. These uplifts and values have not been included in WebTAG, but provide an indicative order of magnitude of the benefits. The results are not intended to provide precise estimates but may be used to help judge the Value for Money of a scheme.

Benefit to Cost Ratio

4.1.7 The Benefit Cost Ratio (BCR) considers the impacts to the economy, society, the environment and the public accounts. It offers an estimate of the value of benefit generated for every £1 of public expenditure on a project or scheme.

4.1.8 The Initial BCR is constructed using the DfT's WebTAG guidance. WebTAG Unit 3.5.4 provides advice on monetising the benefits and costs of a transport intervention and also outlines the different assumptions for the appraisal of such impacts.

4.1.9 Benefits and costs that contribute to the Initial BCR can be presented in the Analysis of Monetised Costs and Benefits (AMCB) Table.

4.1.10 The Initial BCR defines the initial Value for Money category. Proposals are judged to offer poor, low, medium, high and very high Value for Money based on the BCR boundaries. These categories include:

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 Poor VfM if BCR is below 1.0  Low VfM if the BCR is between 1.0 and 1.5  Medium VfM if the BCR is between 1.5 and 2.0  High VfM if the BCR is between 2.0 and 4.0  Very High VfM if the BCR is greater than 4.0

4.1.11 The Value for Money assessment should then account for quantitative and qualitative information. The following sections of this advice note provide more advice on the use of this information, construction of the BCR and final Value for Money categorisation.

Presentation of a Range for the Benefit Cost Ratio

4.1.12 Given that Benefit Cost Ratios are responsive to changes in key parameters, the presentation of only a central BCR estimate is unlikely to provide a full picture of the VfM of a scheme. Scheme assessments should therefore include a range of sensitivity tests and these can be determined on a case-by-case basis. Typically however, the expectation is that the BCR is reported in a range determined by the high and low demand forecast upon which the appraisal is based and the high and low ranges for the Value of Travel Time Savings. Where cost ranges are available, these should also form the basis of an additional range along with sensitivities around any key assumptions that are material to the decision in a proportionate way.

Value for Money Statement

4.1.13 A Value for Money statement (Chapter 6) provides a summary of the conclusions from the Value for Money assessment. The statement should provide a concise summary of the economic, social, environmental, and public account, impacts that transport interventions may have and, based upon these, give advice for investment boards and Ministers about the economic case for a proposal.

4.1.14 A VfM statement, summarising the conclusions from the VfM assessment, should be included within the body of submissions to Department for Transport investment boards and Ministers. It is usually included in the Economic Case section of submissions. The VfM statement should report:

 the VfM category of the scheme  the present value of benefits, present of costs, and the range around the Benefit Cost Ratio (see below for further detail)  a concise summary of benefits and costs have been assessed, including any assumptions that influence the results  assessment of non-monetised impacts  identification of any key risks, sensitivities and uncertainties

4.2 Highway Model Results and Interpretation

4.2.1 The main outcomes of the work is presented in the next section ‘Economic ‘TUBA’ Appraisal’. This section introduces the highway model analysis that was undertaken and describes the tools that key analysis tools used to ensure full understanding of the impacts of the schemes.

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Future Year Highway Model Understanding

4.2.2 A comprehensive review of the model has been undertaken and this deep understanding of the workings of the model has been further developed in the studying of the model’s response to the Option 1A scheme. The analysis tools use are geared towards understanding of routeing changes and changes to delays, and also a detailed analysis of the impact on travel time for all journeys being undertaken. This complete analysis ensure that no impacts are overlooked and equally importantly that there are no unrealistic impacts that could skew the economic analysis.

4.2.3 The key analysis tools are:

 Flow difference maps showing clearly the changes in traffic flow (in 2031) that would be expected as a result of the scheme;  Delay difference maps which are critical to understanding of the impact as these changes drive the changes in route choice;  A sector based analysis of change in travel time due to the scheme (in 2031)

4.2.4 These analyses, which have been studied at length, provide an ongoing review of the model in addition to their primary purpose of establishing the impact of the scheme.

4.2.5 Although, as described above, an ‘interim’ AM peak and inter-peak model have been added the analyses are usually only shown and discussed for the PM peak model.

Sector System

4.2.6 The sector system mentioned above provides manageable way of observing changes in travel time by grouping model zones together in a suitable way so as to provide to balance convenience and detailed required. As such the sector are more detailed in the areas where highest impacts are expected and larger further from the scheme.

4.2.7 The sectors are constructed by aggregating model zones with alignment to local authority boundaries to enable wider understanding without knowledge of the model. Sevenoaks and Tonbridge & Malling Districts are divided into smaller sectors as the scheme impact is expected to vary across these districts. The sector system is shown in Figure 7.

4.3 Economic ‘TUBA’ Appraisal

Introduction

4.3.1 Following 2015 validation of the model (reported in Chapter 3) this study now introduces the analysis of the future years 2021 and 2031 with and without the scheme. At this point we also introduce the economic appraisal work (using TUBA) and include this in the model runs and analysis.

4.3.2 The approach taken is to report that analysis in the order in which it was undertaken.

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Scheme Costs: Option 1A - M25 Junction 5 East Facing Slips

4.3.3 TAG Unit A1.2 – Scheme Costs provides guidance on estimating scheme investment and operating costs, including on applying adjustments for risk and optimism bias. This section describes how the outputs from that guidance are reported in the Department’s standard tables.

4.3.4 The TUBA Manual 5.3.2 states that for construction costs, account must be taken of any change in the cost of road construction relative to the general price level. This used to be done in TUBA by using the Relative Price Factor (RPF). However, the current WebTAG Unit A-2 ‘Scheme Costs’7 recommends the use of inflation rates relevant to the delivery of transport schemes. These should now be used in the preparation of base cost inputs for TUBA.

4.3.5 The 2009 Study described the calculation of scheme costs, noting a headline scheme cost of £77.4m (2008 prices). We have not updated this cost estimate as part of this study, but it is possible that the project costs could have increased over and above any further price base changes (that are considered implicitly in the scheme appraisal). Such changes could arise due to scope changes (for example, through stronger environmental mitigation measures) and/or due to specific real cost inflation affecting particular cost components (say, differentially affecting labour or technology costs). We consider the potential impact on the scheme appraisal of an increase in underlying costs as part of a ‘low benefit, high cost’ sensitivity, as reported in Test 5c below.

4.3.6 The price base used in the economic analysis is 2010.

4.4 Outcomes of Highway Model Actions

4.4.1 A series of highway model runs and economic analyses were undertaken. These were a combination of improvements, corrections and sensitivity tests (described in Chapter 3) with the objective being to attain a robust assessment with a thorough understanding of the likely upper and lower limits in the economic outputs such as the benefit to cost ratio (BCR).

4.4.2 A description of the analyses undertaken is described below with the impacts on the Analysis of Monetised Cost and Benefits (AMCB) summarised in Table 8

Test T1: Replicating the PB Study

4.4.3 The first exercise was to rerun the economic analysis with the highway models as they were received. The TUBA run files from the previous study were not available.

4.4.4 Running the highway models as received and replicating the TUBA runs from the information available (and using updated TUBA economics and 2010 price base) resulted in a BCR of 2.32, broadly similar the 2.23 BCR reported in the 2009 Study.

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Test T2: Value of Time and Fuel Costs (Improvement)

4.4.5 Updating of the highway model values of time and fuel led to a small decrease in the present value of benefits (PVB) and hence the BCR.

Test T3: Convergence (Improvement)

4.4.6 Improvements to the convergence of the highway model in accordance with current WebTAG recommendation led to an increase in the PVB and BCR. This is because with better convergence route choices are better optimised.

Test T4: Model Periods (Improvement)

4.4.7 The previous modelling used a PM peak hour model only to provide the highway model inputs to the economic appraisal. The interim creation of AM peak and inter-peak models has revealed that the PM peak only modelling led to over-estimation of benefits. The use of all three highway model periods has a negative impact on the BCR.

Test T5: Scheme Coding (Correction)

4.4.8 The distance and speed correction resulted in a significant impact on the PVB and BCR.

Impacts on Analysis of Monetised Cost and Benefits (AMCB)

4.4.9 Table 8 summarises the economic outcomes of the model improvements and corrections. Test T5 was adopted as the final improved version of the SATURN highway model to take forward to further analysis and sensitivity testing.

4.4.10 Although the adjustments have caused some significant reduction in PVB and BCR this is recovered to a degree by consideration of annualisation factors (see Section 4.8).

Table 8. Summary of AMCB Results – Model Improvement PVB PVC NPV TEST BCR (£M) (£M) (£M)

0 As received (PB 2009 Study) 119 53 66 2.23

1 As received (Rerun using standard TUBA 2010 price base) 135 58 77 2.32

2 Value of Time and Fuel Costs Updated 110 58 52 1.89

3 Convergence Enhancements 142 58 84 2.44

4 AM Peak and Inter-Peak Matrices Added 97 58 39 1.67

5 Scheme Coding Corrections 69 58 11 1.19

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4.5 Scheme Impact of Option 1A – Junction 5 East-Facing Slips

4.5.1 Figure 1 (full model) and Figure 2 (zoomed to area of effect) are flow difference maps showing the changes in traffic flow (in 2031) that would be expected as a result of the scheme. Figure 3 shows a similar area to Figure 2 making use of improved visualisation making use of google mapping.

4.5.2 There are two key routeing impacts due to the scheme which are as follows:

 Movement along A25 is transferring to M26 This is the impact that is most expected as a result of the scheme.

 Movement from M25 Junctions 3-4 and M20 Junction 1-3 is transferring to M25 Junctions 4-5 and M26 This impact is less obvious. It is facilitated by the additional east facing slips effectively freeing all movements through use of the M25/A21/A25 junction for a u-turn.

4.5.3 Figure 4 shows a map-based diagram of the above impacts.

Figure 1. Flow Difference Due to Option 1A (2031 PM) (Full Model)

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Figure 2. Flow Difference Due to Option 1A (2031 PM) (Zoomed)

Figure 3. Flow Difference Due to Option 1A (2031 PM) (Google Image)

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Figure 4. Flow Difference Due to Option 1A (2031 PM) (Indicative Diagram of Key Impacts)

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4.6 Scheme Impact of Option 2C – A225 Otford Slips

4.6.1 Figure 5 (zoomed to area of effect) is a flow difference map showing the changes in traffic flow (in 2031) that would be expected as a result of the scheme. The figure is comparable to Figure 2 which is the equivalent for Option 1A and the traffic flow resulted are similar in terms of movement along A25 is transferring to M26.

Figure 5. Flow Difference Due to Option 2C (2031 PM) (Zoomed)

4.7 Further Analysis of Option 1A and 2C

4.7.1 Table 9, Table 10 and Table 11 show in more detail the changing traffic flow on the A25 between the A21 near Riverhead and Wrotham Heath as result of Option 1A and Option 2C. The tables shows this for all vehicles, cars and HGVs respectively, are the figures are the traffic total for both directions.

4.7.2 The key outcomes are:

 On average there is a reduction of around 100 cars (6-7%) on the A25 as result of Option 1A  The reduction varies along the route and peak in Borough Green where the reduction is over 200 vehicles (20%)  In Option 2C reduction on the A25 between Riverhead and Bat and Ball is not seen due to the location of the slips roads on A225 Otford Road

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Table 9. Change in Traffic Flow on A25 (2031 PM Peak) (ALL VEHICLES) NO LOCATION OP 1A DIFF % OP 2C DIFF % SCHEME

A21 <> Riverhead 1943 1916 -27 -1% 1925 -18 -1%

Riverhead <> Bat and Ball 1791 1624 -167 -9% 1811 20 1%

Bat and Ball <> Seal 1193 1058 -135 -11% 1008 -185 -15%

Seal <> Borough Green 1437 1287 -150 -10% 1254 -182 -13%

Borough Green 1221 1003 -218 -18% 972 -249 -20%

Borough Green <> A20 / M20 J2A 1409 1292 -117 -8% 1250 -158 -11%

Wrotham Heath 2060 2101 42 2% 2100 40 2%

Average 1579 1469 -110 -7% 1474 -105 -7%

Table 10. Change in Traffic Flow on A25 (2031 PM Peak) (CARS) NO LOCATION OP 1A DIFF % OP 2C DIFF % SCHEME

A21 <> Riverhead 1913 1889 -25 -1% 1894 -20 -1%

Riverhead <> Bat and Ball 1754 1591 -163 -9% 1772 18 1%

Bat and Ball <> Seal 1160 1029 -131 -11% 988 -171 -15%

Seal <> Borough Green 1387 1244 -143 -10% 1220 -168 -12%

Borough Green 1158 954 -203 -18% 925 -233 -20%

Borough Green <> A20 / M20 J2A 1339 1236 -103 -8% 1197 -142 -11%

Wrotham Heath 1993 2032 39 2% 2027 34 2%

Average 1529 1425 -104 -7% 1432 -97 -6%

Table 11. Change in Traffic Flow on A25 (2031 PM Peak) (HGVs) NO LOCATION OP 1A DIFF % OP 2C DIFF % SCHEME

A21 <> Riverhead 30 27 -3 -9% 32 1 5%

Riverhead <> Bat and Ball 37 33 -4 -11% 39 2 6%

Bat and Ball <> Seal 33 29 -4 -12% 19 -13 -41%

Seal <> Borough Green 49 43 -6 -13% 35 -14 -29%

Borough Green 63 49 -14 -23% 48 -16 -25%

Borough Green <> A20 / M20 J2A 70 56 -14 -20% 54 -16 -23%

Wrotham Heath 67 69 2 3% 73 6 9%

Average 50 44 -6 -12% 43 -7 -14%

4.7.3 Table 12 highlights a key issue for Option 2C which is resulting additional traffic on the A225 Otford Road between M26 and Bat and Ball.

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Table 12. Change in Traffic Flow on A225 Otford Road (2031 PM Peak)

NO LOCATION OP 1A DIFF % OP 2C DIFF % SCHEME

All VEHICLES 1327 1326 -1 0% 1524 197 15%

Cars 1310 1309 -1 0% 1495 184 14%

HGVs 17 17 0 0% 29 12 75%

Link-based Delay Analysis

4.7.4 Figure 6 shows a SATURN delay difference maps showing the changes in traffic delay per vehicle (in 2031) that would be expected as a result of the scheme. The blue bars denote a reduction in delay as a result of the schemes and the green bars denote an increase in delay.

Figure 6. Delay per Vehicle (seconds) Difference Due to Option 1A (2031 PM) (Zoomed)

4.7.5 The reduction in traffic on the A25 leads to a significant reduction in delays along the A25 as shown by the blue bars.

4.7.6 Table 13 and Table 14 show in more detail the resulting travel times on the A25 between the A21 near Riverhead and Wrotham Heath.

 Overall the model reports potential travel time saving of up to around a minute (3-4%) for journeys in both direction along this stretch of road.

The savings vary along the routes, they are largest between Bat and Ball and Seal.

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4.7.7 The corresponding increase in traffic on the M26 leads to small increased delays of a few seconds along the M26.

Table 13. Change in EASTBOUND Travel Time on A25 (2031 PM Peak) (SECONDS) NO LOCATION OP 1A DIFF % OP 2C DIFF % SCHEME

A21 <> Riverhead 136 145 8 6% 139 3 2%

Riverhead <> Bat and Ball 153 141 -12 -8% 154 1 0%

Bat and Ball <> Seal 178 168 -10 -6% 161 -18 -10%

Seal <> Borough Green 445 422 -22 -5% 410 -35 -8%

Borough Green 13 12 0 -2% 12 0 -2%

Borough Green <> A20 / M20 J2A 195 188 -7 -4% 184 -11 -6%

Wrotham Heath 259 262 4 1% 268 10 4%

Total 1378 1339 -39 -3% 1327 -51 -4%

Table 14. Change in WESTBOUND Travel Time on A25 (2031 PM Peak) (SECONDS) NO LOCATION OP 1A DIFF % OP 2C DIFF % SCHEME

A21 <> Riverhead 116 113 -3 -3% 115 -1 -1%

Riverhead <> Bat and Ball 105 101 -4 -4% 104 -1 -1%

Bat and Ball <> Seal 167 155 -12 -7% 154 -14 -8%

Seal <> Borough Green 349 344 -6 -2% 344 -5 -2%

Borough Green 13 14 1 10% 14 1 9%

Borough Green <> A20 / M20 J2A 161 153 -8 -5% 152 -9 -6%

Wrotham Heath 416 408 -8 -2% 409 -7 -2%

Total 1328 1288 -40 -3% 1291 -36 -3%

4.7.8 Sector Analysis of Origin-Destination Travel Time

4.7.9 Figure 7 shows the sector system used for this analysis as described earlier. Figure 8 shows sector based analysis of all travel times, without and with the scheme (in 2031).

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Figure 7. Sector System

Figure 8. Sector based analysis of change in travel time Option 1A (2031 PM) (seconds)

Sevenoaks West Sevenoaks East Sevenoaks District North Sevenoaks District South Sevenoaks Westerham Tonbridge and Malling Central Tonbridge Aylesford, Ditton, Snodland Maidstone District West Maidstone District East Maidstone Tunbridge Wells DistrictTunbridge Wells and North Rochester Medway and Gillingham Chatham / Canterbury / M2 East Thanet / AshfordM20 East / Folkestone (town) A20 East A21 South towards Hastings A25 towards West Westerham M25 West M25 (DartfordNorth Crossing) Overall Sevenoaks West 6 -9 1 -1 -4 -34 -2 -252 -253 -36 -245 0 -2 -75 -267 -275 -314 -298 0 0 14 -1 -12 Sevenoaks East -5 -8 -9 0 -4 -14 -5 -14 -17 -30 -14 1 -4 -9 -12 -23 -13 -14 1 -16 6 -6 -6 Sevenoaks District North -4 -12 -1 -6 -10 -36 -8 -27 -30 -36 -30 -5 -8 8 -5 -27 -23 -21 -6 -8 7 -5 -6 Sevenoaks District South 0 -9 -3 0 0 -12 -3 -89 -62 -21 -75 -4 -11 8 -80 -85 -84 -91 -9 0 8 1 -4 Westerham -1 1 4 0 5 -38 -7 -335 -327 -105 -275 -5 -10 -8 -373 -324 -250 -310 -7 1 11 12 -6 Tonbridge and Malling Central -25 -14 -6 -1 -17 -1 -1 0 -6 -12 -13 -3 -3 3 -9 -11 -10 -6 -6 -37 7 -2 -5 Tonbridge -1 -11 -6 0 1 -5 -1 -7 -17 -16 -9 0 -2 -15 -9 -6 -14 -24 0 0 7 0 -3 Ditton, Aylesford, Snodland -290 -6 -11 -42 -348 -2 -6 -1 -3 -5 -1 -3 -2 3 0 2 0 3 -5 -382 5 -19 -4 Maidstone -254 -14 -5 -22 -302 -3 -2 0 -1 -1 0 -6 -2 0 0 0 -1 -1 -4 -332 2 -5 -1 Maidstone District West -19 -23 -10 -1 -39 -1 -1 1 -2 -1 -1 -5 -1 3 1 -2 -4 -2 -2 -55 15 -9 -1 Maidstone District East -322 -13 -7 -25 -374 -3 -4 2 -4 -2 0 -3 -2 0 1 0 0 0 -3 -407 4 0 -2 Tunbridge Wells 3 -8 4 -2 2 -4 1 -5 -14 -8 -16 -4 -3 -17 -16 -32 -28 -34 -6 2 8 1 -4 Tunbridge Wells District 3 -6 5 1 1 -3 0 -4 -4 -2 -6 -5 -1 -9 -7 -18 -22 -2 -1 0 7 6 -2 Rochester and North Medway -200 -15 -5 -35 -271 4 -7 3 -3 -2 -1 12 9 2 -2 -1 0 6 -8 -251 3 0 -1 Chatham and Gillingham -344 -13 -14 -17 -361 -3 -12 -1 -3 -2 0 0 -2 -2 0 -1 0 0 -3 -398 6 1 -1 M2 East / Canterbury / Thanet -288 -13 -7 -30 -379 -4 5 -1 -6 -3 0 -4 -4 -1 0 -3 -409 5 0 -1 M20 East / Ashford (town) / Folkestone -274 -13 -4 -47 -365 -3 4 -2 -4 -2 -1 -4 1 -1 -1 0 -414 5 -8 -2 A20 East -270 -13 -3 -51 -359 -4 -8 -2 -1 -2 -1 -8 -4 0 -1 0 -4 -414 6 -8 -3 A21 South towards Hastings 5 -4 6 1 2 -2 1 -3 1 -1 -2 0 0 -3 -2 -3 -1 1 8 1 2 A25 West towards Westerham -4 -5 -1 0 10 -49 -7 -473 -467 -131 -473 -4 -8 -1 -389 -448 -548 -500 -5 -1 -10 M25 West -23 -29 -15 -32 -25 -18 -33 19 19 -3 13 -28 -33 13 18 18 18 3 -30 -26 -1 4 M25 North (Dartford Crossing) -16 -26 -1 -28 -24 -2 -30 -7 -9 0 -8 -26 -38 -2 -7 -3 -18 -10 -27 -25 3 -6 Overall -11 -13 -2 -2 -13 -8 -6 -1 -4 -5 -4 -4 -4 0 -1 0 -2 -1 -13 -39 5 -2 -2 4.7.10 The key outcomes from this analysis are:

 The scheme results in travel time savings of up to around 8 minutes for journey transferring from the A25 to the M26. This is shown by the green highlighted cells.

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 Journeys which remain on or need to use the A25 for access are also experiencing small benefits due to less traffic and less delay on the A25 between Sevenoaks and Wrotham Heath. These savings are smaller – up to around 30 seconds.

4.8 Outcomes of Highway Model and TUBA Sensitivity Tests

4.8.1 A series of sensitivity tests were undertaken to increase confidence and robustness of the modelling and to provide more information on the likely range in the economic outputs. Good practice recommends that the BCR should be presented as a likely range rather than one figure. Table 15 shows the impact of these tests on the Analysis of Monetised Cost and Benefits (AMCB).

Test 5a: Weekends added

4.8.2 The default annualisation settings assume 1518 inter-peak hours per year. However this only represent the six hour period (10am-4pm) on weekdays. It is considered that the scheme benefits will be experienced to a significant degree at weekend (and the off- peak/evening and early morning period – see below). In this test we assume that weekends benefits are included as the equivalent of 12 hours (per day) of inter-peak conditions.

 12 hours * 2 days * 52 weeks = 1248 additional inter-peak effective hours

Test 5b: Weekday off-peak added

4.8.3 In this test we assume six further additional inter-peak equivalent hours to overnight hours to account for the period from 7pm to 7am.

 6 hours * 5 days * 52 weeks = 1560 additional inter-peak effective hours

Test 5c: Construction Costs

4.8.4 This test assumes a 15% increase in the construction costs. This test recognises that the project costs have not been updated since the 2009 study, other than through general any price base changes implicitly included in the scheme appraisal, and could have increased significantly due to scope changes and/or specific real cost inflations affecting particular cost components.

Test 5d: Large Development at Westerham

4.8.5 Although at the extremity of the highway model it was considered that the location of a large development at Westerham could provide some additional benefit.

4.8.6 Assuming 1000 dwellings and typical trip rates this would result in approximately:

 200 origin trips in AM peak hour

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 100 origin and 100 destination trip in inter-peak hour  200 destination trips in PM peak hour

4.8.7 The additional trips are applied to zone 61187 in 2031 only.

Table 15. Summary of AMCB Results – Sensitivity Tests

PVB PVC NPV TEST BCR (£M) (£M) (£M)

5 Improved Model 69 58 11 1.19

5a Weekends added 81 58 23 1.40

5b Weekend and off-peak added 97 58 38 1.66

5c Construction costs +15% (based on test 5) 69 67 2 1.03

Large Development (1000 homes) at Westerham 5d 80 58 22 1.37 (based on 5b Weekend and off-peak added)

4.9 Economic Analysis of Option 2C

4.9.1 Table 16 shows the outcome of the economic analysis for Option 2C compared to Option 1A. The present value of benefits (PVB) for this option is shown to be nearly halved compared to Option 1A. However, it should be considered that the cost of the scheme is likely to be much lower and the sensitivity of this is demonstrated in Table 16.

Table 16. Summary of AMCB Results – Option 2C

PVB PVC NPV TEST BCR (£M) (£M) (£M)

5b Option 1A Junction 5 Slips 78 58 19 1.335

6b Option 2C Otford Slips (same construction price assumed) 41 58 -18 0.699

6b Otford Slips (halved construction price assumed) 41 29 12 1.397

4.10 Quantification and Monetisation of Other Benefits

4.10.1 In addition to the standard economic TEE and AMCB tables inputs the highway model can be used to provide a range of further monetary and quantitative assessment to inform the appraisal. These include:

 Economic: Land-use value benefits (this is covered in Chapter 5)  Environmental: Noise and Air Quality, both local areas of and further afield  Social: Quality of Life, Severance and Safety and Accidents

4.10.2 The following quantitative assessment have been included in the overall assessment (Chapter 6) alongside a supporting the respective relevant indicator and their qualitative remarks.

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Global (Full Model) Travel Distance Indicator

4.10.3 Table 17 shows a comparison of total travel distance in 2031 (in vehicle kilometres) for without the scheme, Option 1A (Junction 5 east-facing slips) and Option 2C (Otford)

Table 17. Global Change in Travel Distance (2031) (Vehicle Kilometres)

NO OP 1A DIFF % OP 2C DIFF % SCHEME

2031 AM Peak 2,861,299 2,859,332 -1,967 -0.07% 2,861,284 -16 0.00%

2031 Inter-Peak 1,980,301 1,979,356 -945 -0.05% 1,980,376 75 0.00%

2031 PM Peak 2,868,127 2,866,598 -1,529 -0.05% 2,868,339 212 0.01%

4.10.4 This indicator is used to support the following items in the appraisal summary table in Chapter 6:

 ECONOMIC Vehicle Flow – Wider Impacts  SOCIAL Safety and Accidents

Global (Full Model) Travel Time Indicator

4.10.5 Table 18 shows a comparison of total travel time in 2031 (in vehicle hours) for without the scheme, Option 1A (Junction 5 east-facing slips) and Option 2C (Otford Road east- facing slips).

Table 18. Global Change in Travel Time (Vehicle Hours)

NO OP 1A DIFF % OP 2C DIFF % SCHEME

2031 AM Peak 55,607 55,489 -118 -0.21% 55,543 -64 -0.11%

2031 Inter-Peak 29,146 29,118 -28 -0.10% 29,132 -14 -0.05%

2031 PM Peak 54,117 54,056 -61 -0.11% 54,078 -40 -0.07%

4.10.6 This indicator is used to support the following items in the appraisal summary table in Chapter 6:

 ECONOMIC Connectivity / Travel Time

Local (A25) Traffic Flow Indicator

4.10.7 Table 19 summarises average total (two-way) traffic flow on the A25 between the A21 near Riverhead and Wrotham Heath. This is effectively a summary of Table 9, Table 10 and Table 11.

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Table 19. Change in Traffic Flow on A25 (2031 PM Peak)

NO LOCATION OP 1A DIFF % OP 2C DIFF % SCHEME

All Vehicles 1579 1469 -110 -7% 1474 -105 -7%

Cars 1529 1425 -104 -7% 1432 -97 -6%

HGVs 50 44 -6 -12% 43 -7 -14%

4.10.8 This indicator is used to support the following items in the appraisal summary table in Chapter 6.

 ECONOMIC Vehicle Flow – Local Impacts  ENVIRONMENTAL Noise and Air Quality  SOCIAL Quality of Life and Severance

Local (A225 Otford Road) Traffic Flow Indicator

4.10.9 Table 20 shows average total (two-way) traffic flow on the A225 between the M26 and Bat and Ball. This is a repetition of Table 12.

Table 20. Change in Traffic Flow on A225 Otford Road (2031 PM Peak) (HGVs)

NO LOCATION OP 1A DIFF % OP 2C DIFF % SCHEME

All VEHICLES 1327 1326 -1 0% 1524 197 15%

Cars 1310 1309 -1 0% 1495 184 14%

HGVs 17 17 0 0% 29 12 75%

4.10.10 This indicator is used to support the following items in the appraisal summary table in Chapter 6:

 ECONOMIC Vehicle Flow – Local Impacts

Local (A25) Travel Time Indicator

4.10.11 Table 21 summarises travel time on the A25 between the A21 near Riverhead and Wrotham Heath. It is effectively a summary of Table 13 and Table 14.

Table 21. Travel Time on A25 (2031 PM Peak) (SECONDS)

NO LOCATION OP 1A DIFF % OP 2C DIFF % SCHEME

Eastbound (A21 to Wrotham Heath) 1378 1339 -39 -3% 1327 -51 -4%

Westbound (Wrotham Heath to A21) 1328 1288 -40 -3% 1291 -36 -3%

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4.10.12 This indicator is used to support the following items in the appraisal summary table in Chapter 6:

 ECONOMIC Connectivity / Travel Time

Safety and Accidents Monetary Calculation

4.10.13 The TAG Data Book contains the following tables of monetary values for the prevention of casualties:

 A4.1.1: Average value of prevention per casualty by severity and element of cost  A4.1.2: Average value of prevention per road casualty by class of road user

4.10.14 Being a matrix-based program, TUBA cannot calculate accident rates and benefits as these are based on link flows and road standards.

4.10.15 Table 22 shows a calculation of the monetary value of potential accident savings due to the reduction in travel distance. This is included in the AMCB table in Chapter 6 to demonstrate the potential impact.

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Table 22. Accident Assessment

OPTION 1A OPTION 2C

PCU km saved AM Peak Hour -1,967 -16 Inter-peak -945 75 PM Peak Hour -1,529 212 Annualisation Factors AM Peak Hour 759 759 Inter-peak 4326 4326 PM Peak Hour 759 759 Annualised Change in Vehicle kilometres AM Peak Hour -1,493,105 -11,765 Inter-peak -4,085,907 324,883 PM Peak Hour -1,160,663 161,136 Total -6,739,675 474,254 Kent Casualty Rate 2010 - 2014 (per million vehicle km) All casualties 0.41 0.41 KSI 0.03 0.03 Change in Number of Accidents per year All casualties -2.76 0.19 KSI -0.20 0.01 Accident Cost All casualties £77,825 £77,825 KSI £235,791 £235,791 Cost Change per year All casualties -£215,051 £15,133 KSI -£47,675 £3,355 Cost change - 60 year discounted period (multiply by 20.67) All casualties -£5,591,402 £15,133 KSI -£1,239,556 £3,355 Total -£6,830,958 £18,487

4.10.16 This could be regarded as a conservative estimate because there are likely to be further saving resulting from moving traffic from an ‘A’ road to a motorway.

Land-Use Value Gain Monetisation

4.10.17 This is also included as a potential ‘what-if’ scenario based on the analysis described in Chapter 5.

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5. WIDER ECONOMIC BENEFITS

5.1 Introduction

5.1.1 The work on the wider economy effects of better access to the M26 has considered three areas:

 Land use benefits arising from use of land for residential development;  Direct employment impacts due to better access to employment sites; and  The scope for greater labour market integration within Kent, through better accessibility and reduced journey times.

5.2 Land use benefits from residential development

Background

5.2.1 Guidance on transport appraisal now includes the specific situation where residential development is enabled by a transport scheme, and the Department for Transport’s appraisal guidance, WebTAG, sets out how an appraisal is to be undertaken5. In brief, this requires the appraisal to identify residential development that would not take place without the transport project – termed dependent housing - and to value that development as the uplift in land value associated with the development. Land value uplift benefits that arise when transport measures affect development are likely to be substantial in the study area, reflecting the final values of completed properties and the relatively low alternative use value of land used for agriculture. The background research and subsequent analysis has followed the principles enunciated in the WebTAG guidance, but does not include detailed research to assess potential changes in land values. WebTAG indicates the use of data from the Government Valuation Office Agency as a starting point, but recommends the using specific valuations for the locations under consideration when undertaking an appraisal.

5.2.2 The identification of dependent housing is complicated by the fact that the current situation is very fluid in planning terms, as local authorities are re-assessing land availability and housing targets. Measures which fail to deliver housing or “divert” housing to second best locations represent a substantial loss of benefits, and consequently delivery of new housing delivers large benefits which, in a properly functioning market, are captured as land value uplift. For example, one consequence of a lack of housing is growth in shared living, such as grownup children remaining at home with parents because they are unable to form a new household in the area where they would prefer to live. Enabling new household formation delivers benefits to the new household group and to others involved in shared living.

5.2.3 Another consequence is where people move to other areas because the housing that is available within their preferred market area is outside what can be afforded at the income level of the would-be purchaser. Areas which offer a high quality of life and fast

5 See WebTAG guidance for the appraisal practitioner: TAG Unit A2-3. https://www.gov.uk/government/publications/webtag-tag-unit-a2-3-transport-appraisal-in-the-context-of- dependent-development

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travel times to London attract commuters who have highly productive jobs located outside their area of residence. In the absence of housing supply, people who cannot access (externally located) highly paid jobs, for example because of a lack of skills or qualifications, will be those most likely to migrate or to remain at home with parents or in shared accommodation. In turn, migration can limit the ability of an area to attract business investment, unless the area is accessible from other lower-wage areas. The provision of land for housing is therefore closely linked with employment growth; where people and jobs do not “match” locally, some of the difference is addressed through commuting between areas. A key benefit of transport is that it extends effective labour markets to improve the matching between demand for and supply of skills.

5.2.4 In the appraisal of options, it is important to identify the value of benefits from residential development that can be attributed to transport infrastructure. This depends on how much housing is constrained by a lack of or poor transport infrastructure, and the value uplift compared with having development take place in other locations or not happen at all or to a reduced density or significantly extended timescale. Planning and other factors also exert significant influence on what goes where, and planning policies are in turn influenced by decisions on transport investment.

The Kent & Medway Growth and Infrastructure Framework and Strategic Housing Market Assessments

5.2.5 The Kent & Medway Growth and Infrastructure Framework document (GIF6) is a top- down analysis of population and employment changes across the whole of Kent and Medway, and provides forecasts of housing, people and jobs for each council area for the period 2011 to 2031 (and therefore includes developments already approved up to May 2015 when the GIF was published). The GIF aims to present an overall balance between demand and supply, so that, for example, the jobs forecast is the matching of additional labour supply with labour demand. The key forecasts for Tonbridge & Malling and Sevenoaks Council areas provide for: increases in housing numbers of 13,300 and 3,600 respectively; population increases of 28,200 and only 1,600 respectively for each authority; and additional jobs of 7,700 for Tonbridge & Malling and 7,000 for Sevenoaks.

5.2.6 The GIF estimates are at some variance with those generated through a number of “bottom up” forecasting exercises undertaken by district and borough councils, including economic forecasts and Strategic Housing Market Assessments (SHMA).

Strategic Housing Market Assessments

5.2.7 The Economic Futures Forecasting Report for Tonbridge & Malling of January 20147 identifies a large increase in labour supply in the Borough, which was modelled through the SHMA. Additional labour supply is forecast to be 11,272 to 2031 (labour market scenario): to maintain existing levels of inward and outward travel to work, labour demand would also have to increase by this amount. The labour supply forecast is consistent with an increase in dwellings of 11,461 and an increase in population of 21,2408. However, this report indicated a baseline labour demand increase of 8,410

6 Kent & Medway GIF, Aecom, September 2015 7 Nathaniel Lichfield & Partners, January 2014 (see also addendum of December 2014) 8 Ibid, table 3.6.

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across all sectors, and what is described as a policy-on scenario (with, for example, regeneration initiatives) increasing labour demand to 9,950. This imbalance between supply and demand implies additional net outward travel to work.

5.2.8 The report was updated in December 2014 based on the SHMA Addendum which presented an objectively assessed housing need in Tonbridge & Malling of 12,513 dwellings (626 per annum), following the release of the 2012-based Sub-National Population Projections. However, in response to market signals and evidence of suppressed household formation, this was adjusted to 13,300 or 665 dwellings per annum9. The June 2015 SHMA Update10 identified an objectively assessed need for 646 dwellings per annum, but when allowance was made for London migration (as part of a sensitivity analysis) and an affordability uplift, an alternative forecast of 673 dwellings per annum ( a total of 13,640 dwellings) was presented11.

5.2.9 The report revised the labour supply forecast to 12,459 for Tonbridge & Malling, also between 2011 and 2031, an average requirement of 623 jobs per annum in order to maintain existing levels of travel to work. The December 2014 Addendum to the Economic Futures Forecasting Report continued to identify a baseline scenario in which labour demand increases by 8,410 and a policy-on scenario in which labour demand increases by 9,950. Both scenarios are lower than the annual average growth observed between 1997 and 2011, and both imply an increase in net outward commuting to jobs elsewhere.

5.2.10 The Strategic Housing Market Assessment reported for Sevenoaks and Tunbridge Wells in September 2015 (Strategic Housing Market Assessment Final Report for Sevenoaks and Tunbridge Wells Councils12). This indicated that an appropriate trend-based demographic projection would see population growth of 19,900 in Sevenoaks in the period 2013-33 (an increase of 17.0%). The demographic-led need for dwellings would amount to 524 dwellings per annum13, a total of 10,480 over the period 2013-33).

5.2.11 This projection required modification on the basis of likely economic growth and changes in migration. The East of England Forecasting Model suggested that employment could grow by between 8.9% and 16.5% in Sevenoaks over the period 2013-33. If this quantum of growth were achieved, it would generate higher in- migration to Sevenoaks relative to past trends, and consequently the demographic-led projections require to be adjusted upwards14. The report identified an objectively assessed need for additional housing units of 12,400 in Sevenoaks (620 dwellings per annum) between 2013 and 2033, the additional 96 dwellings per annum being required to address affordability and to support economic growth. Both needs assessments indicate significantly more dwellings than identified in the GIF. It should, however, be

9 As reported in the Addendum Report, December 2014 by Nathaniel Lichfield & Partners 10 GL Hearn, SMHA Implications of 2012-Based Household Projections 11 GL Hearn, SHMA Final Report, September 2015 12 GL Hearn, SHMA Final Report, September 2015 13 Comprising a base demographic need of 516 and 8 for out-migration from London: Ibid, Figure 1. 14 GL Hearn Sevenoaks & Tunbridge Wells SHMA Final Report September 2015. The report also highlights housing affordability issues in Sevenoaks; it follows that the forecast economic growth would need to comprise high-value jobs in order to attract people to migrate there without adding to the underlying affordability problem. Most available evidence suggests that high value jobs will cluster in London.

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noted that the GIF was assessing potential market equilibria between supply and demand, not unconstrained need or demand as is the case with the SMHA process.

Use of SHMAs

5.2.12 The SHMAs set out an objective assessment of the need for housing to address population growth, economic growth, migration and issues such as suppressed household formation which are a symptom of “affordability” issues. Need is not what is termed effective demand, that is, demand backed by willingness and ability to pay. In many areas, people who need housing exceed the numbers able to pay the going market prices. Scarcity relative to need gives rise to property prices that are well in excess of building and associated costs of housing, and consequently the high residual land values which characterise many parts of the region under consideration.

5.2.13 The objective assessment of housing needs, undertaken at the district or borough council level, is followed by a “call for sites”. Landowners and others submit sites which form a list of potential sites for assessment. There is then a site by site assessment which will generate a land availability assessment. Sites are assessed on the basis of suitability, availability and whether development is achievable during the period of the (next) local plan. The assessment includes a review of constraints, including a Green Belt review, which typically reduces the number of sites, and can result in a potential volume being identified to meet the assessed need. Proposals for use of sites are reviewed by a Planning Inspector, which could lead to sites being added back in or new ones having to be found.

5.2.14 The SHMAs do not set housing targets, and it is for the local Councils to bring together evidence of housing need, with information regarding available land, environmental and policy constraints, including Green Belt, and issues related to delivering infrastructure, through the plan-making process to set housing targets.

Tonbridge & Malling

5.2.15 A large proportion of Tonbridge & Malling’s land is in the Green Belt, which will be expected to limit options available for development. Overall however, Tonbridge & Malling is almost certainly going to be able to meet its post-2015 assessed housing need; this amounts to some 5,000 to 7,000 housing units, in addition to development already in place since 2011. This need can be met by further development at Kings Hill and at other sites close to the boundary with Maidstone, plus more limited development around Tonbridge itself.

5.2.16 The Borough could, however, face an increase in labour supply which is greater than the forecast increase in labour demand (see paragraph 0). Depending on the outcome of policy measures to increase the numbers of jobs in the Borough, net outward commuting could increase by between 1,300 and 2,800 people. Depending on the characteristics of outward commuters, this could create additional demands for travel to work to locations in Kent, Surrey or into London. The latter would tend to be people travelling to high-productivity jobs, which would benefit the Borough through re-cycling

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of salaries locally15; such commuting implies demand for additional capacity by rail and possibly for housing close to railway stations.

Sevenoaks

5.2.17 Sevenoaks Council’s Core Strategy for the period 2006-2026 looked for the development of 3,300 houses (165 per year). Of these at least two thirds were to be located in Swanley, Sevenoaks and Edenbridge and at least half in Swanley and Sevenoaks. This would enable the Green Belt to be protected. The more recent Allocations and Development Management Plan (ADMP) notes that completions (2006-2014) and permissions amounted to 2,755 units16. In an update at 1 April 2014, the Council identified a housing land supply of 4,282 units for the period 2006-2026, excluding 450 units at Fort Halstead. On this basis there was an apparent oversupply of land for residential development. Most if not all of the 3,300 target would be achieved through development of three sites at Westerham to the west of Sevenoaks, with some being met at two sites north of the Bat and Ball junction.

5.2.18 However, Sevenoaks has an objectively assessed housing need of 12,400 dwellings in the period 2013-33, which is significantly in excess of the ADMP target and the Council’s identified land supply. Therefore, one reasonable observation might be that Sevenoaks will be under pressure to develop more than just 3,300 new housing units in order to address economic growth, migration and affordability issues.

5.2.19 In common with Tonbridge & Malling, a high proportion of Sevenoaks District is Green Belt17 or of outstanding natural beauty (or both), and therefore it is likely that this and other constraints will mean that the emerging Local Plan will not identify enough suitable or achievable land to enable the need for 620 dwellings per annum to be achieved.

5.2.20 In view of the constraints in the Green Belt and in the M25-M26 corridor, a high proportion of any additional development in Sevenoaks District is likely to take place in Swanley and Edenbridge, rather than in Sevenoaks itself or in the immediate surrounding area. The only potential large new residential development in proximity to Sevenoaks is at Fort Halstead, a former MOD site. In addition to new industrial and commercial investment, the site could be developed for up to 450 houses at current rural densities of 40 per hectare18. This density indicates a predominance of “family” type housing and therefore potentially providing accommodation for 850-950 people. The location would not be impacted by any of the potential locations for east facing slips to the M26.

Potential for including dependent housing benefits

5.2.21 For there to be a dependent housing benefit to be considered within the transport appraisal, that housing has to be dependent on the transport project. This implies that there must one or more sites in the M26 / M25 corridor where there is potential for

15 That is, induced demand as part of a local multiplier process. 16 Allocations and Development Management Plan 2015, para 3.5. 17 It is claimed that 93% of the land area is Green Belt. 18 An average lot size of 250 m2.

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development but where development cannot go ahead because of the impacts of that development on the level of service of the transport network. The economic case also requires a substantial level of development with significant uplift in land values.

5.2.22 The test of dependency to be applied according to WebTAG19 is whether the residential development would cause a significant deterioration in the level of service or increase in costs to existing transport users. The point at which a significant deterioration would occur depends on the scale, location and timing of any potentially dependent development. In the absence of a site or sites that Councils would wish to include in their future Local Plans but where there are likely to be significant transport constraints, it is currently not feasible to point to a site and to assess the possible scale of a dependent housing benefit.

5.2.23 Nonetheless, a hypothetical example is useful as a way of looking at the potential value of possible sites whose development could be linked to the creation of new access to the M26 / M25. For example, if a new large scale development site could accommodate up to 3,500 dwellings20 but only 1,000 dwellings could be built before causing a significant deterioration in the level of service or increase in costs to existing transport user, 2,500 houses could be considered to be “dependent”. The benefits from “dependent” housing comprise planning gain less net external costs caused by the “dependent” housing, where planning gain is the uplift in land value when consent is given to the housing development. This amounts to residential land value less existing land value. The latter is usually agricultural value, but might not always be the case.

5.2.24 While land value data could be used (where available), it is possible to drill down into the value data, which might be necessary to confirm the estimates obtained using land value data. WebTAG recommends gathering local data from surveyors and property and land agents, and this should be done if the study is extended to a full appraisal of the housing benefits. However, based on data from a report by the Government’s Valuation Office Agency21 (VOA), the private benefit of 2,500 “dependent” houses can be calculated22.

5.2.25 To undertake the calculation, it is necessary to create one or more plausible scenarios for development and to use credible land values. The VOA report does not quote values for the study area; for the South East values range from £1.4million per ha for the Medway Towns to £4.0 million for Oxford. For locations in the M26 / M25 corridor, a value of £2.0 million appears appropriate23, with an agricultural land value of £25,000 per ha. As the requirement is to generate a present value, a critical consideration is the timing and phasing of development, which can be illustrated using scenarios to indicate the scale of potential benefits.

19 See WebTAG guidance for the appraisal practitioner: TAG Unit A2-3. https://www.gov.uk/government/publications/webtag-tag-unit-a2-3-transport-appraisal-in-the-context-of- dependent-development 20 At a density of some 40 dwellings per hectare on a site of around 85 to 90 hectares. 21 See VOA’s Property Market Report 2011, which provides values of land by type and region during 2010 at https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/371470/pmr_2011.pdf 22 That is, ignoring external effects such as loss of visual amenity that do not form part of private benefit. 23 A higher value would be appropriate in locations that had good rail access as well as road access.

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5.2.26 For illustration, two development scenarios have been considered:

 Slow growth - in which none of the new development takes place prior to 2020 when 2 ha are developed, after which only 2 ha are developed each year until 2026, when 4 ha are assumed to be developed, after which the rate of development increases to 10 ha per annum from 2028 to 2031. Development ceases at the end of 2031 when the land needed to accommodate 2,500 dependent houses is fully developed. The net present value of planning gain using this scenario is £67.57 million (discounted to 2010, in 2010 prices); and

 More rapid growth - in which 4 ha are developed in 2020, increasing in increments of 2 ha per annum until 2023 when 10 ha are developed per annum until 2026, with a final 4.5 ha being developed in 2027. The net present value of planning gain using this scenario is £77.13 million (discounted to 2010, in 2010 prices).

5.2.27 The value of planning gain would of course be greater if all 3,500 houses were “dependent” and if development took off earlier and more rapidly24. Further work, including gathering data on land values, would be required to refine this appraisal. Nonetheless, the scenarios give an outline of what “dependent” housing development would add to the transport appraisal. As noted above the key issue here is the test of dependency, with this requiring more detailed assessment of the distribution of journeys to and from the new developments and their implications on the local and wider road networks.

5.2.28 These are potentially large benefits, and therefore while more substance cannot be given to a dependent housing component at the present time, it is suggested that the scope for enabling housing that would be dependent be kept under review as part of the overall planning process, with a view to making a more positive case for improved motorway access sometime in the future.

Employment land

5.2.29 The review identified only small potential employment sites within the area of Sevenoaks, Tonbridge & Malling and Maidstone; an important characteristic of the area is that there is considerable pressure to allow change of use of sites and premises from employment to residential use.

Tonbridge & Malling

5.2.30 In Tonbridge & Malling a study by Nathaniel Lichfield and Partners (NLP 2014) estimated that up to 33 ha could be required to serve employment land needs to 2031. This was based on the highest of four employment growth scenarios, in which future demand for employment space could be up to some 393,960 metres squared with a land requirement of 92.7ha. Demand was expected to be chiefly for B1c/B2/B8 uses. As there is an estimated 63ha of land available allowing for various factors the consultants indicated a potential shortfall of up to 33ha. Given the existing sites, and the balance

24 If all development were deemed dependent, with a 2020 start and a maximum development rate of 10 ha per annum, the NPV of planning gain would be £103.58 million (discounted to 2010, in 2010 prices).

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between demand and supply, the shortfall is for industrial uses, while there could be a small surplus of land for office developments.

5.2.31 In the A25 / M26 corridor (corresponding roughly to NLP’s Malling Area and Medway Gap Rural Area), demand for all industrial and commercial uses is local and low in quantity, despite good accessibility in the latter area. The Council will undertake a further review of land requirements in financial year 2016-17.

Sevenoaks

5.2.32 In Sevenoaks District there is only limited evidence of demand for new employment land, which was said by Council economic development personnel to be due to a known lack of availability deterring prospective firms from bothering to look for employment sites. The Council’s Allocation and Development Management Plan (ADMP 2011) to 2026 states that, post-recession, demand for manufacturing space continued to decline, demand for office space was flat, while demand for storage and distribution space was growing in line with the economy. The ADMP identifies total provision of 79.6 ha of employment land, of which 75.5ha is existing sites excluding Major Developed Sites. In the Sevenoaks urban area the ADMP identifies 27.1ha with an additional 3.7ha at Westerham. Of the total of 30.8ha, 29ha is allocated for offices plus other development, including industry, warehousing and residential development. It is known that there is pressure to have some locations in the urban area re-allocated for conversion to residential use.

5.2.33 The above excludes Major Developed Sites. There is a planned employment and residential development at Fort Halstead, which could meet demand for employment land in this area. This is a former MOD site which is used by defence related industries, but a major user, Defence Science and Technology Laboratory, will vacate the site by 2018. Sevenoaks Council hopes to replace some 1,200 jobs that will be lost in 2018, but recognises that redevelopment will not be possible solely as an employment-led development. Therefore, while Fort Halstead has potential for office use, clean industries, business incubators and research facilities, plus a possible hotel development, a major element of the regeneration plan is the development of around 450 residential units. Fort Halstead is therefore allocated as a Major Employment Site within the Green Belt. As well as being within the Green Belt and an AONB, the site currently suffers from poor access, and it is recognised that spending on access infrastructure will be required if the regeneration plan is to succeed.

Other Locations

5.2.34 It is likely that better access to the M26 would have very little impact on demand for employment land in Tonbridge & Malling Borough or Sevenoaks District, apart from an indirect effect whereby better access enables residential developments to go ahead, which in turn would create demands for local services which would require land, principally for retail and local office-based services. However, better accessibility could affect the rate and/or scale of development of two sites just over the county boundary, namely:

 Moorhouse Tile Works, which was formerly used by Redland Tiles; and  Biggin Hill airport.

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5.2.35 Enhanced development at these locations would provide employment opportunities for Kent residents. Better accessibility for Kent residents to these sites could reasonably be expected to increase the share of Kent residents in total employment on both these sites25.

5.2.36 The scale of the possible employment impacts are difficult to judge. In the case of the Moorhouse Tile Works site, a planning application for B8 use (storage and distribution) was made to Tandridge District Council in 2015 by Roxhill Developments. The application, for 20,938m2 of space, was rejected. It is understood that Amazon was a possible user of the space, had consent been granted. It is possible that a modified application will be submitted and that at some point the site will be used for distribution activities. In terms of employment, 20,000m2 of large scale high bay distribution space would generate around 180 – 250 jobs26 within the distribution facility, plus jobs for heavy and light goods vehicle drivers and for support activities such as vehicle maintenance.

5.2.37 A review of the planning officer’s report on the application27 indicates that the information provided in the application created uncertainties with regard to the likely traffic impacts of the development. The report identified 15 constraints on development, of which road classification was one constraint. The principal issues were, however, the fact that the proposal was for development in the Green Belt and AONB. Objectors cited potential traffic impacts, in particular Sundridge with Ide Parish Council highlighted the impacts of additional traffic along the A25, noting the likely adverse impacts on air quality, access to properties, congestion, parking outside local business premises and quality of life in general.

5.2.38 The future of this proposal is currently uncertain. Given the number and the nature of the constraints cited, it is unlikely that measures which reduce traffic on the A25 will by themselves enable development to go ahead, and therefore the development cannot be regarded as dependent on transport infrastructure investment. However, if other issues are addressed in a future application, transport could then be the “deal breaker”, with the development becoming conditional on measures that address impacts along the A25.

5.2.39 With regard to Biggin Hill, it is currently not possible to make reliable estimates of how better access to the M26 could affect development there. However, it is possible to use scenarios to illustrate what could happen.

5.2.40 It is well known that there are ambitious plans to develop sites at and closely adjoining the infrastructure that comprises the airport. Biggin Hill Airport Ltd (BHAL) has aspirations to create an additional 2,300 jobs28 over the next 20 years, in three phases.

25 There is of course a potential two-way street effect, as residents of East Sussex would be better able to compete for jobs in west Kent due to better accessibility to those jobs. 26 The estimate of 250 jobs is based on data in the report Employment Densities by Arup in 2001 for English Partnerships. However, as warehouse activity has been increasingly automated, the figure of 200 jobs is probably more realistic. 27 Tandridge District Council Application 2015/1217. http://tdccomweb.tandridge.gov.uk/Planning/lg/GFPlanningDocuments.page 28 This is a central estimate: note that all job numbers here have been rounded to the nearest 100.

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The development builds upon airport activities which are solely based around business and general aviation, involves relatively small numbers of air travellers. Both the users of business aviation services and people working in support of these services are characterised by high earnings (and high productivity), and therefore making productive use of time is a commercial imperative. Consequently time saved while travelling by business aviation users and by people working in support of these services has a much higher than average value.

5.2.41 The intended growth in employment could require around 80,000 to 90,000m2 of floorspace, roughly half of which would be refurbished or relocated space. The estimated employment gain could potentially be higher, as it does not include “densification” in the use of premises by existing or new businesses. The scale and timing of development depends upon a range of factors, including how planning issues are addressed regarding development in the Green Belt, the overall growth of business aviation activity especially in the greater London area, competition from Le Bourget and other airports for activities that serve business aviation. The resolution of planning issues is critical, because businesses need to be confident that they can expand on site or close by as business expands.

5.2.42 In broad terms, the phasing of development at Biggin Hill over the 20 year period is as follows:  Phase 1, 600-700 jobs, of which the main component would be original equipment manufacturers;  Phase 2, 500-600 jobs, where the main components would be aircraft management and sales, downstream maintenance and service providers and specialist technical support companies such as software and avionics; and  Phase 3, 1,000 – 1,200 jobs principally offices and manufacturing.

5.2.43 The first phases of development are predicated on attracting business air services and support, including servicing and maintenance by aircraft manufacturers. While historically business aviation has grown at roughly twice the rate of growth of GDP, this relationship might not continue into the short or even medium term, thanks to low rates of economic growth and global uncertainties about major markets including China. Similarly it is unclear how information technology will affect demand for travel; while most evidence suggests that technology has actually increased demand for face to face business interaction, further advances might have the opposite effect.

5.2.44 Setting aside planning issues and future growth in business aviation, Biggin Hill’s “offer” to a competitive market for mobile investment associated with business aviation is affected by a range of factors that include surface access. Access is important not only for aviation users but also for staff employed by businesses located there. Various reports have highlighted the poor quality of surface access to the north towards Bromley, but access to the M25 is also poor. The M25 lies within 4 miles of the airport boundary, but the closest junctions are junction 4 (using the A233 and A21), and junction 6. It is also possible to access and leave the M25 at junction 5, involving use of the A25 and A233.

5.2.45 In discussions, BHAL has noted that aviation-related jobs include very specialist occupations which will involve drawing on a small and potentially highly dispersed

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labour pool, and that poor accessibility is likely to affect how possible recruits will view the prospect of working at Biggin Hill. The ability of Kent-based workers to access Biggin Hill will therefore affect the share of Kent-based workers in the workforce at the airport site.

5.2.46 Given that both the workforce and the locations of off-site suppliers and service providers is likely to be highly dispersed, access from both north and south of the airport will be important. In particular, if suppliers have clustered mainly around larger airports such as Heathrow and Gatwick then access to and from the M25 will be important. BHAL has suggested that between 50% and 60% of traffic to and from the airport uses the A25 from either the Sevenoaks or Godstone direction; this includes both employees and logistics and operational traffic.

5.2.47 It is unclear whether poor access currently affects staff recruitment or retention or the attraction of business investment, and similarly there is no evidence on which to base estimates of how access might affect the rate of growth of employment. However, for illustrative purposes three scenarios have been considered:

 Section 1 - Central estimate for employment at Biggin Hill remains unchanged, but that better access accelerates employment growth by 5% each year from 2020 for 10 years, with employment growth slowing in the last three years of Phase 329. If each job creates £85,000 of GVA per annum (in 2010 prices), this scenario adds £17.1 million to GVA over the 20 year horizon when the stream of additional GVA is discounted at 3.5% to a 2010 base;

 Scenario 2 - with the same assumptions, a lower final “build out” to 1,800 jobs would add a cumulative GVA total of £14.5 million; and

 Scenario 3 - using the same GVA and acceleration effect of 5%, it is assumed that this effect continues from 2020 to 2035, so that the total number of jobs in 2035 is fractionally under 2,400 instead of constrained to 2,300. Under this scenario, the cumulative GVA impact amounts to £25.5 million.

5.2.48 These GVA scenarios cannot simply be added to the transport analysis. As part of the guidance on wider impacts, the WebTAG guidance considers the case where workers move to more productive jobs. This is likely to be the case here, as the types of skills required for the jobs likely to be located at Biggin Hill tend to be in high demand and therefore the people moving to these jobs leave other jobs. If the labour resource is treated as fixed and if all labour is fully employed, there must be adjustments across the economy involving other job movements, ultimately creating a loss of output in other sectors which has to be netted out. Alternatively, jobs that become vacant due to people moving to more productive jobs can be filled by new people entering the labour market, which is arguably the more reasonable assumption to make.

5.2.49 Therefore the approach set out in WebTAG can be adopted30, but with the caveat that the transport benefits which lead to people moving to more productive jobs are not

29 So that the total remains 2,300 jobs. 30 See https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/427091/webtag-tag- unit-a2-1-wider-impacts.pdf

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included, and therefore the benefits are an under-estimate. WebTAG defines the wider benefit (that is, in addition to the transport benefit) to be the change in tax revenues that results from the labour market impacts. This is to be estimated from the change in GVA from the move to more productive jobs. This is estimated to be 30% of the change in GVA arising from the move to more productive jobs. On this basis, the wider impacts would be:

 Scenario 1 £5.14 million  Scenario 2 £4.35 million  Scenario 3 £7.65 million.

5.2.50 It is stressed that the above are simply scenarios, but they are useful as a means of indicating how better accessibility could affect the value of development of a strategic site to the South East. The value that accrues specifically to Kent would necessarily be lower, depending on the numbers of Kent residents who secure employment at the site. It should be noted that these scenarios do not include multiplier effects such as supply chain linkages; it is assumed that resources are at or close to full employment, so that the creation of demands on suppliers does not generate new output31.

Labour market integration

5.2.51 The analysis of labour market integration looked for evidence that, for some origin- destination pairs, travel to work trips by car were “missing”, when compared with other origin-destination pairs within the same region. “Missing” trips could indicate that transport factors deter travel between these origin-destination pairs and might therefore reduce the degree of labour market integration in the region. Where labour markets are not well joined up, employers might find it harder to recruit the right staff, which imposes a cost on businesses and lowers aggregate productivity. Employers might also find it difficult to retain skilled staff, for example where transport issues cause someone to move to a less productive job which involves a lower commute cost compared with travelling to a more productive job. Commute costs include travel time, convenience and flexibility as well as car-related costs. Again the loss of skilled staff imposes costs on businesses and lowers aggregate productivity.

5.2.52 An analysis of travel to work by car (as car driver) was undertaken using finely grained geographic areas around Tonbridge & Malling, Sevenoaks, Tunbridge Wells, Medway and Maidstone, and less finely grained areas across the remainder of Kent. Several model specifications were tested, all of which used a combination of data on working age population and a proxy for jobs obtained from the travel to work data. The modelling aspects of the analysis and additional details regarding findings are discussed in Appendix A. The analysis was undertaken for all of Kent, but did not include London, the rest of the South East or rest of UK. For rest of South East and rest of UK it is impossible to assign a travel time and therefore it was decided not to include these.

5.2.53 Table 23 shows the results using the final specification of the model; the table shows actual less predicted trips, and therefore a negative number represents a ‘missing’ trip, that is, a trip that might be expected to be made based on the variables shown and the

31 This is an extreme assumption, but it is considered important not to over-state the effects of the proposal by claiming unrealistic multiplier effects.

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calculated journey times by car. Table 24 following shows the sum of actual less predicted trips relative to working age population for each area.

5.2.54 Together these tables show a good fit for all areas with the exception of travel from Sevenoaks West, where actual trips are significantly fewer than those predicted by the model. In terms of destinations, there are significant numbers of “missing” trips from Sevenoaks West to Sevenoaks District North, Tonbridge & Malling Central, Maidstone and Tunbridge Wells. However, there are also “missing” trips from Sevenoaks West to other parts of Kent, in particular to Chatham and Gillingham and Dartford32. There is also a good fit for trips to Sevenoaks West, with minimal under or over-estimation of travel.

Table 23. Actual less predicted trips, separate urban and rural variables

Central

noaks West noaks

Seve East Sevenoaks Sevenoaks North District Sevenoaks South District Westerham & Tonbridge Malling Tonbridge Aylesford, Ditton, Snodland Maidstone Maidstone West District Maidstone East District Wells Tunbridge Wells Tunbridge District Seve noaks West -818 -974 -327 -882 -946 -761 -687 -1,069 -143 -232 -1,074 -483

Sevenoaks East 50 42 -32 -14 -429 -75 -264 -347 -46 -74 -217 -125

Sevenoaks District North 68 612 -79 45 -136 -95 -675 -1,203 -176 -252 -415 -192

Sevenoaks District South -48 -232 -547 -30 -452 -405 -442 -810 -105 -165 -304 -213

Westerham -123 -211 -420 -61 -309 -232 -300 -433 -57 -91 -342 -146

Tonbridge & Malling Central 25 117 13 -20 19 132 134 -85 7 -45 100 170

Tonbridge 49 340 -6 61 35 -259 -90 -269 44 -68 593 207

Ditton, Aylesford, Snodland 8 38 -166 -31 -9 1,182 163 1,083 40 131 -2 115

Maidstone 26 110 -54 -24 9 1,232 267 2,018 718 1,543 215 506

Maidstone District West -15 -176 -541 -73 -50 -340 -120 -501 -1,216 -8 -276 354

Maidstone District East -1 -65 -214 -45 -17 -3 -84 219 -276 160 -125 131

Tunbridge Wells 50 292 52 217 55 97 1,010 -57 -14 54 -20 -104

Tunbridge Wells District -2 22 -123 7 -11 44 523 -85 -16 275 88 -1,368

Source: model estimates: the model uses census population and travel to work data and RAC travel time data; sum of actual less predicted trips relative to working age population

32 Interviews highlighted that north – south travel is also an issue for the Sevenoaks area generally.

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Table 24. Sum of actual less predicted trips relative to working age population ALL KENT IMMEDIATE STUDY AREA Sevenoaks West -2.60 -1.40 Sevenoaks East -0.27 -0.12 Sevenoaks District North -0.14 -0.06 Sevenoaks District South -0.64 -0.34 Westerham -0.99 -0.50 Tonbridge & Malling Central -0.04 0.02 Tonbridge -0.07 0.02 Ditton, Aylesford, Snodland 0.05 0.09 Maidstone 0.10 0.09 Maidstone District West -0.61 -0.23 Maidstone District East -0.12 -0.01 Tunbridge Wells 0.00 0.03 Tunbridge Wells District -0.08 -0.02 Source: model estimates from census and travel to work data and RAC travel time data

5.2.55 The above findings suggest that, while travel times and costs by road are likely to be among the factors affecting travel by car, there are other factors at work as well. This is especially the case in relation to Sevenoaks West. One factor is likely to be a lack of “fit” between skills within the working age population in the Sevenoaks area and jobs in areas such as Maidstone. This lack of fit would tend to make residents of these areas travel elsewhere for work. It is also likely that people with jobs elsewhere have chosen to live in locations such as Sevenoaks West, East and Westerham because of the high amenity of these areas and their road and rail links.

5.2.56 Therefore a second factor that is likely to be important, especially in the case of Sevenoaks West and East and also Westerham, is travel into Sussex and Greater London, including travel by train rather than by car. Table 25 shows propensities to travel (trips per 100 people of working age) for travel to London, Surrey and the rest of the South East for travel as car driver and by train. This shows that for all of the Sevenoaks sub- areas and Westerham, the propensity to travel to London is high, with Dartford being the only other area with comparable propensities to travel to London33.

33 Dartford has the highest propensity of all areas to travel to London by car, with a “score” of 14. Sevenoaks North has a ”score” of 13 for travel to London by car.

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Table 25. Propensity to travel to London, Surrey and Rest of South East CAR DRIVER TRAIN34

London Surrey Rest of SE London Sevenoaks West 5 1 1 21 Sevenoaks East 4 1 1 18 Sevenoaks District North 13 1 1 10 Sevenoaks District South 6 5 4 9 Westerham 10 5 2 10 Tonbridge & Malling Central 6 1 1 7 Tonbridge 3 1 1 10 Ditton, Aylesford, Snodland 5 1 1 2 Maidstone 3 0 1 2 Maidstone District West 3 0 1 6 Maidstone District East 3 0 1 4 Tunbridge Wells 2 1 4 9 Tunbridge Wells District 2 0 3 6 Rochester and North Medway 6 0 0 3 Chatham and Gillingham 3 0 0 4 Dartford 14 0 0 10 Gravesham 7 0 0 5

Source: model estimate from census and travel to work data and RAC travel time data

5.2.57 This analysis suggests that factors other than measured journey times have a significant influence on travel to work within the immediate study area. In particular, the very large differences in travel between Sevenoaks and Maidstone and Tonbridge & Malling and Maidstone suggest that other factors are dominant. These might include differences in socio-economic characteristics within the populations, differences in types of jobs and differences between the journey times used for the analysis and journey times that are experienced by people who travel or those that are perceived by people who choose not to travel (for work).

5.2.58 Table 26 shows a further analysis of travel to work and census data. This indicates that, of the areas under consideration, Sevenoaks residents display a higher propensity to travel to work locations that are outside the defined “local” sub-region. Sevenoaks could be considered to perform a stronger role as an exporter of labour to the wider economy of South East England than the other areas considered here, with the exception of Dartford. This is true whether one considers all travel modes or travel as driver of a car or van. These differences appear not to be due to the proportion of residents of working age who are working, as these ratios are similar for all areas. A more likely explanation is, therefore, that differences in socio-economic and/or skills composition underlie the particular characteristics of Sevenoaks’ labour supply, especially when compared with Maidstone and Tonbridge & Malling.

34 Train travel to Surrey and Rest of South East was negligible.

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5.2.59 From this analysis a strong case cannot be made for the project on the basis of how it would help integrate the sub-regional economy and in particular open up job opportunities in Maidstone for Sevenoaks residents and vice-versa. The analysis indicates that constraints on accessibility between Maidstone and Sevenoaks play only a limited role in explaining the lower than expected level of travel to work between these areas. The data on earnings indicate that neither area offers highly paid (high productivity) jobs, relative the South East region. Therefore the incentives to residents to make the journey between Maidstone and Sevenoaks for work are low, especially when Sevenoaks benefits from good accessibility to the London conurbation, including relatively fast rail access to several main stations in London. As noted above, Sevenoaks has particular socio-economic characteristics which make it different: it seems likely that good accessibility plus other factors such as the local environment have enabled Sevenoaks to attract a greater number of people with high end skills, compared with other areas in Kent on the edge of the London conurbation. This is reflected in the relatively high earnings that accrue to residents.

5.2.60 It therefore appears to be the case that relatively poor accessibility between Sevenoaks and Maidstone has a limited effect on economic performance, and therefore it could be difficult to make a strong case based around achieving greater labour market integration by improving accessibility within the sub-region as defined here.

Other benefits

5.2.61 In addition to the wider benefits considered here, it is important to note that a significant reduction in traffic on the A25 will deliver environmental and amenity benefits to residents of towns and villages on this route, and these constitute benefits that are in addition to those that arise due to new housing.

5.2.62 In standard transport appraisal (following WebTAG), benefits such as reduced noise, improved air quality and reduced severance would be captured outside the economic appraisal. However, in principle, and also in keeping with Green Book appraisal principles, such benefits could be monetised as part of the full cost benefit appraisal. This would be achieved by applying appropriate willingness to pay values to those effects for which physical measurements of impacts can be obtained. This would, however, require the analysis also to capture any negative externalities from the “dependent” housing (either within the “dependent” housing analysis or within the environment analysis, avoiding double counting). For example, additional residents might cause more local congestion, such as traffic making school runs.

5.2.63 This has not been considered here, in the absence of data on physical impacts of reduced traffic on the A25 or on the external effects arising from the development of “dependent” housing.

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Table 26. Analysis of travel to work data

PLACE OF RESIDENCE TOTAL WORKING AS TRAVEL TO WORK IN TRAVEL TO WORK IN WORKING IN AREA TRAVELLING TO PERCENTAGE OF “LOCAL” SUB- “LOCAL” SUB- OF RESIDENCE AS “NON-LOCAL” WORKING AGE REGION REGION PERCENTAGE OF AREAS TO WORK AS POPULATION (EXCLUDING AREA (EXCLUDING AREA TOTAL WORKING PERCENTAGE OF OF RESIDENCE) AS OF RESIDENCE) AS RESIDENTS TOTAL WORKING PERCENTAGE OF PERCENTAGE OF RESIDENTS TOTAL TRAVEL TO TOTAL WORKING WORK OUTSIDE RESIDENTS AREA OF RESIDENCE

% % % % %

Sevenoaks 55.2 26.9 19.0 29.5 51.5

Tonbridge & Malling 57.9 55.8 35.5 36.4 28.1

Maidstone 56.9 54.6 27.5 49.6 22.9

Tunbridge Wells 55.8 37.6 18.9 49.7 31.4

Dartford 59.9 20.8 13.8 33.8 52.4

Gravesham 55.0 48.7 32.4 33.5 34.1

Medway 55.4 44.9 21.8 51.4 26.8

Source: calculated from Census 2011 and NOMIS data

List of Consultees

5.2.64 The following individuals were consulted in connection with our assessment of the Wider Economic Impacts. We would like to thanks all for their cooperation and insights provided.

 Tonbridge & Malling Borough Council: Ian Bailey (Planning Policy Manager) and Jeremy Whitaker (Economic Regeneration Officer)  Sevenoaks Borough Council: Emily Haskell (Economic Development Officer) and Simon Taylor (Planning Officer - Planning Policy)  Kent County Council: Nicholas Abrahams (Economic Development)  Biggin Hill Airport: Bethany Russell (Policy and External Affairs Coordinator)

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6. OVERALL VALUE FOR MONEY CASE

6.1 WebTAG Appraisal Table

6.1.1 The value for money case is one of the key components of any major scheme business case in providing a concise summary of the primary economic, social, environmental and public account impacts that transport interventions may have. Whilst initially focused on the monetised benefit cost ratio developed from the TEE and associated table, the value of money case draws together both quantified and qualitative assessments, primarily from Tasks 4 and 5. We also check for consistency with any earlier value for money assessments (explaining any significant changes as required) as well as with the qualitative review of scheme benefits and dis-benefits identified.

6.1.2 A key aspect is be to ensure that all opportunities and issues are considered in order to strengthen and ensure robustness of the economic case, including where possible monetisation of additional impacts, such as environmental, social and health. To ensure this we are making use of the WebTAG Appraisal Table Templates as shown in Figure 9 and at www.gov.uk/government/publications/webtag-appraisal-tables.

Figure 9. WebTAG Appraisal Summary Table Template Appraisal Summary Table Date produced: Contact:

Name of scheme: Name Description of scheme: Organisation Role Promoter/Official Impacts Summary of key impacts Assessment Quantitative Qualitative Monetary Distributional £(NPV) 7-pt scale/ vulnerable grp Business users & transport Value of journey time changes(£) providers Net journey time changes (£) 0 to 2min 2 to 5min > 5min

Economy

Reliability impact on Business users Regeneration Wider Impacts Noise Air Quality Greenhouse gases Change in non-traded carbon over 60y (CO2e) Change in traded carbon over 60y (CO2e) Landscape

Environmental Tow nscape Historic Environment Biodiversity Water Environment Commuting and Other users Value of journey time changes(£) Net journey time changes (£)

Social 0 to 2min 2 to 5min > 5min

Reliability impact on Commuting and Other users Physical activity Journey quality Accidents Security Access to services Affordability Severance Option and non-use values Cost to Broad Transport Budget

Public Indirect Tax Revenues Accounts

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Table 27. Appraisal Summary Table (Part 1) A225 Otford Monetary Impacts Junction 5 Slips (Option 1A) A233 Westerham (Option 2C) Test Description: PB Report Rerun Final HIGH Final LOW HIGH Test Code: T0 T1 T5b Diff to T1 T5c T6b Diff to 1A ECONOMIC (£000s) Analysis of Monetised Costs and Benefits (calculated by TUBA) Greenhouse Gases 815 1,267 1,883 616 1,275 644 -1,239 Economic Efficiency: Consumer Users (Commuting) 21,143 17,940 -3,203 16,124 10,044 -7,896 Economic Efficiency: Consumer Users (Other) 55,725 39,673 -16,052 25,621 20,726 -18,947 Economic Efficiency: Consumer Users (All) 56,360 76,868 57,613 -19,255 41,745 30,770 -26,843 Economic Efficiency: Business Users and Providers 62,205 59,987 41,054 -18,933 28,664 21,854 -19,200 Wider Public Finances (Indirect Taxation Revenues) -3,025 -4,030 -1,005 -2,729 -1,277 2,753 Present Value of Benefits (PVB) 119,380 135,097 96,520 -38,577 68,955 51,991 -44,529

Present Value of Costs (PVC) 53,529 58,114 58,114 0 66,831 29,057 -29,057

OVERALL IMPACTS Net Present Value (NPV) 65,851 76,983 38,406 -38,577 2,124 22,934 -15,472 Benefit to Cost Ratio (BCR) 2.23 2.32 1.66 -0.66 1.03 1.79 0.13

Items not Calculated by TUBA but recommended for inclusion by WebTAG Accidents Saving Value Gain (see Chapter 4) 5,591 5,591 -15 PVB including impact of accidents 102,111 74,546 51,976 BCR including impact of accidents 1.76 1.12 1.79 Noise Not considered Local Air Quality Not considered Journey Quality Not considered Physical Activity Negligible

Further Items (see Chapter 5) Land-use value gain 77,000 77,000 PVB including impact of land-use value gain 179,111 151,546 BCR including impact of land-use value gain 3.08 2.27

Qualitative and Non-Monetary Quantitative Junction 5 Slips (Option 1A) A225 Otford (Option 2C) A233 Westerham

ECONOMIC

 Significant relief for A25  Significant relief for A25  Limited relief to A25 Vehicle Flow - Wider Impacts  Access to A21 s/b for journeys  Avoids additional direct south of Sevenoaks pressure to J5 and A21

Quantitative Evidence (see Chapter 4):

Change in PM Peak Vehicle Kilometres  -1967 -0.07% = -16 0.00% Change in PM Peak Car Kilometres  -945 -0.05% = 75 0.00% Change in PM Peak HGV Kilometres  -1,529 -0.05%  212 0.01%

 Increased traffic flow via Vehicle Flow - Local Impacts `  Implications for A225 Westerham accessing M25 Quantitative Evidence (see Chapter 4): Change in PM Peak Vehicle Flow on A25 between A21  -110 -7%  -105 -7% and Wrotham Heath Change in PM Peak Car Flow on A25 between A21 and  -104 -7%  -97 -6% Wrotham Heath Change in PM Peak HGV Flow on A25 between A21 and  -6 -12%  -7 -14% Wrotham Heath

Change in PM Peak Vehicle Flow on A225 Otford Road = -1 0%  197 15% between M26 and Bat and Ball Change in PM Peak Car Flow on A225 Otford Road = -1 0%  184 14% between M26 and Bat and Ball Change in PM Peak HGV Flow on A225 Otford Road = 0 0%  12 75% between M26 and Bat and Ball

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Table 28. Appraisal Summary Table (Part 2) Qualitative and Non-Monetary Quantitative Junction 5 Slips (Option 1A) A225 Otford (Option 2C) A233 Westerham

 Little or no expected benefit for  Slips provide good direct  Slips provide good direct access to Sevenoaks from the east Connectivity / Travel Time access to Sevenoaks, Maidstone access to Sevenoaks and employment opportunities.  Access to Biggin Hill / Oxted

Quantitative Evidence (see Chapter 4): Change in PM Peak Vehicle Hours  -118 -0.21%  -64 -0.11% Change in PM Peak Car Hours  -28 -0.10%  -14 -0.05% Change in PM Peak HGV Hours  -61 -0.11%  -40 -0.07% Change in PM Peak EASTBOUND Travel time on A25  -39 -3%  -51 -4% between A21 and Wrotham Heath (SECONDS) Change in PM Peak WESTBOUND Travel time on A25  -40 -3%  -36 -3% between A21 and Wrotham Heath (SECONDS) Travel time Savings for East-West Movements Up to 8  tranferring from A25 to M26 mins

 Improved motorway  Improved motorway  Improved motorway Network Reliability and Resilience resilience, but local implications resilience, but local implications resilience, but local implications

 Greatest accessibility impact  Local accessibility impacts  Local accessibility impacts Dependent Housing but support to new housing sites may provide support to new may provide support to local will be location specific location specific housing sites sites and in Biggin Hill

 Larger catchment area for  Larger catchment area for = Limited increases employer Employment Support Maidstone area employers in Maidstone area employers in access to workers accessing Sevenoaks workers accessing Sevenoaks workers

ENVIRONMENTAL  Reduced traffic flows on A25  Reduced traffic flows on A25  Limited local noise and air Noise and Air Quality may improve local noise/ air may improve local noise/ air quality impacts expected on A25 quality east of Sevenoaks quality east of Sevenoaks Quantitative Evidence (see Chapter 4): Change in PM Peak Vehicle Flow on A25  -110 -7%  -105 -7% Change in PM Peak Car Flow on A25  -104 -7%  -97 -6% Change in PM Peak HGV Flow on A25  -6 -12%  -7 -14%

 Reduced impacts due to  Reduced impacts due to = Limited impacts due to Limited Climate Change decrease in vehicle-km decrease in vehicle-km changes in vehicle-km

=/ Impacts depend on design. Landscape  Impacts depend on design  Impacts depend on design Existing multi-level junction

SOCIAL

 Potential benefits in Seal,  Potential benefits in Seal,  Limited local noise and air Borough Green on A25 Borough Green on A25 quality impacts expected on A25 Quality of Life  Very localised impacts  Local impacts possible on the  Local impacts possible in possible near to J5 affecting A225 Westerham Chevening and local area  Reduced local severance in  Reduced local severance in  Potential for increased Severance Seal, Borough Green on A25 Seal, Borough Green on A25 severance around Westerham Quantitative Evidence (see Chapter 4): Change in PM Peak Vehicle Flow on A25  -110 -7%  -105 -7% Change in PM Peak Car Flow on A25  -104 -7%  -97 -6% Change in PM Peak HGV Flow on A25  -6 -12%  -7 -14%

 Likely decrease in vehicle-km  Likely decrease in vehicle-km = Limited impacts of vehicle-km Safety and Accidents on local road network on local road network across the road network Quantitative Evidence (see Chapter 4): Change in PM Peak Vehicle Kilometres  -1967 -0.07% = -16 0.00% Change in PM Peak Car Kilometres  -945 -0.05% = 75 0.00% Change in PM Peak HGV Kilometres  -1,529 -0.05%  212 0.01%

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7. LOCAL STAKEHOLDER CONSULTATION

7.1 Background

7.1.1 There are a number of local sensitivities surrounding the potential location of east facing slips. In partnership with Kent County Council and the Kent Association of Local Councils (KALC) an initial round of stakeholder consultation was undertaken with all local Parish and Town Councils in the Sevenoaks, Tonbridge & Malling, Tunbridge Wells and Maidstone areas to understand the different perceptions of the proposed scheme. Through these contacts responses were received from local political parties. It should be noted that these responses were not part of a comprehensive consultation exercise.

7.1.2 This chapter analyses the consultation responses from the stakeholder group. KALC initiated the consultation sending out a letter and questionnaire in December 2015 and January 2016 with a total of 13 councils responding to the consultation, including the following.

Table 29. Responding Parish & Town Councils Consultees

RESPONDING CONSULTEES:

Borough Green Parish Council Chevening Parish Council Eynsford Parish Council

Goudhurst Parish Council Hawkhurst Parish Council Kensing Parish Council

Leybourne Parish Council Otford Parish Council Platt Parish Council

Riverhead Parish Council Seal Parish Council Wouldham Parish Council

Wrotham Parish Council

7.1.3 Responses were also received from the Tonbridge & Malling Green Party and the Tunbridge Wells Green Party.

7.1.4 The letter set out the objectives of this study to examine the economic feasibility of:

 East facing slips at Junction 5 of the M25 / M26;  East facing slips on the M26 at the A225 near Otford;  East facing slips at the A233 near Westerham; and  Any other locations for east facing slips in the vicinity of Junction 5 of the M25.

7.1.5 The consultation questions focused on the following three specific areas:

1. Journeys that people would like to make, but do not because of the time / inconvenience the journey would involve; 2. Sites that could be developed or existing sites in the area, that have been hampered by a lack of access to the motorway network; and 3. Traffic congestion, network resilience, accessibility or safety issues for motorists, pedestrians and cyclists that could arise if there is a new motorway access to the M25 and M26. ‘

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7.2 Key Findings

7.2.1 While many of the responses received did not provide specific answers on a question by question basis, relevant comments received have therefore been collated from the responses and summarised against each of the three questions stated in the consultation.

7.2.2 The first question focused on any well-known reasons amongst the Parish and Town Councils about its residents opting not to make a journey due to existing difficulties in accessing the M26 (Eastbound). The question was phrased:

‘Are you aware of journeys that people in your area would like to make, for example, to travel further to access job opportunities, but which they do not make now because of the time or inconvenience the journey would involve?

7.2.3 The majority of responses did not highlight specific journeys that were not being made due to the inconvenience / time it takes to access the motorway network and the wider Kent area. Instead, the Parish and Town Councils perceived that commercial vehicles and commuters were still likely to make their journeys via the local highway network rather than the adjacent motorway network. This highlighted existing concerns surrounding congestion, pollution and safety implications for the villages / towns that experience through traffic.

7.2.4 Those who did respond specifically to this question, highlighted:

 A new slip in the vicinity of the M25 J5 would provide missing road capacity to enable better and more reliable access to Sevenoaks Railway Station (Wrotham Parish Council);  Whilst not specifying specific journeys, it was acknowledged that there would be reduced journey times (Wouldham Parish Council).

7.2.5 The second question focused on sites that the Parish and Town Councils considered suitable for development, but were not able to be progressed due to poor access to the motorway network. The question also invited the Parish and Town Councils to highlight existing development sites that they felt were hampered by the poor access and what type of development the Council would either oppose, or support. The question was phrased:

‘Are there sites that you believe could be developed for commercial, industrial, residential or other uses whose development has been hampered by lack of access to the motorway network? If such development(s) were proposed, would the Council support development / what type of development would the Council support / oppose?

7.2.6 The responses indicated that there is a general consensus that local and industrial sites are hampered more by the extreme congestion experienced on the routes used as a ‘rat run’ by HGVs and commuters, which is directly linked to the lack of access to the motorway network.

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7.2.7 Specific sites highlighted amongst the responses included:

 Platt Industrial Estate;  Nepicar Park; and  Fort Halsted.

7.2.8 The responses can be geographically split into two streams, with those that regard the need for improved motorway access to relieve existing pressures and those that perceive the implementation of new east facing slips would simply redistribute the problems rather than provide a long term solution:

 Councils potentially near a new link to the M26 (eastbound) expressed concern about an increase in congestion that would further hamper local businesses; whilst  Councils that currently experience severe congestion and high volumes of HGVs, due to the lack of access to the motorway network, confirmed local businesses were hampered by the congestion experienced on the local highway network.

7.2.9 The third question asked Councils about concerns they had on traffic congestion, network resilience and safety issues that might arise from a new motorway access to the M25 / M26, either through increases or reduction in traffic flows. The question was worded:

Are there any traffic congestion, network resilience, accessibility or safety issues for motorists, pedestrians, cyclists that you think might arise if there are new motorway accesses to the M25 and M26, both from any increases or reductions in traffic flows?

7.2.10 Many of the responses received were applicable to this question, in particular severe congestion, which was identified as acting as a barrier to potential new development as well as existing local businesses in many of the Council areas.

7.2.11 One of the key complaints raised included the number of HGVs using the local highway network as through traffic to access the M26. The key concerns linked with a new motorway access can be summarised as:

 Impact of air quality;  Viability on local businesses because of severe congestion on the local highway network;  Significant maintenance cost on KCC roads because of extreme volume of HGVs; and  Pedestrian and cyclist safety on the local highway network.

7.2.12 As discussed above, the concerns expressed by those consulted are either existing or perceived problems depending on the geographical location of the Council i.e. those close to the proposed scheme and those affected by existing through traffic on the local highway network.

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7.3 General Comments

7.3.1 A total of 15 responses were received. Many of the comments made by the Parish and Town Councils did not specifically answer the questions posed in the consultation letter and have been summarised where possible to provide an overview of the different perspectives. The key findings include:

 Whilst pedestrian crossing facilities on the nearby local highway network enhance safety, they do also aggravate noise and air pollution, by impeding the smooth flow of traffic;  There is no need for the study to investigate further west facing slips, with adequate access to the motorway present;  The need for robust vehicle data / traffic flows, which if not obtained as part of the study, would compromise any perceived conclusion; and  The study should be more wide ranging and consider ways to affect a modal shift in transport, away from the private motor vehicle and towards alternative and more economically, socially and environmentally sustainable means of transport.

7.4 Summary

7.4.1 In summary, the responses can be split between respondents who indicated a) support for a new east facing slip, b) opposed any new east facing slip and c) those who did not confirm either way. In total:

 Six Parish and Town Councils responses indicated general support for a new east facing slip;  A total of three consultees confirmed their opposition to a new east facing slip; and  Six responses neither confirmed support or opposition to a new east facing slip. These respondents either welcomed the study and confirmed they would await the findings of the study before confirming whether they would support or oppose the scheme or perceived the study to be irrelevant to their constituency.

7.4.2 As discussed above, the responses can be geographically split with those that regard the need for improved motorway access to relieve existing pressures and those that are concerned a new east facing slip would simply redistribute the problems. The six respondents who indicated general support for improved motorway access are likely to oppose a scheme that would adversely impact its local highway network or result in a further increase of through-traffic in their locality.

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8. CONCLUSIONS

8.1.1 Our review of the transport and wider economic benefits for the east-facing slip roads suggests some changes in emphasis from the earlier study in 2009.

8.1.2 The transport journey time case for either of the options considered using the transport model is weaker than initially set out in the 2009 report, with only modest localised benefits being apparent from either option, as opposed to some on-line benefits to M26 motorway users apparent in the earlier appraisal. Based on current travel patterns, there will be some net congestion relief on the local road network, primarily on the A25, although flow changes will be modest relative to the wider congestion issues in and around Sevenoaks.

8.1.3 The localised transport benefits will include modest environmental benefits through reduced traffic growth on the A25, although the opportunity to introduce improved pedestrian crossings and cycle facilities, itself a benefit, could erode some of these environmental benefits through impeding free-flow traffic on the core section of the A25 west of Borough Green.

8.1.4 For Option 1A with slip roads at the A21, the economic value of the key transport benefit streams generate a present value of around £70-95m (2010 prices) relative to the present value of the engineering cost of £50-65m (2010 prices). This modest performance reflects the fairly limited and local catchments for the east-facing slip roads and modest traffic flows arising. Both benefits and costs of Option 2C at Otford are expected to be lower, but generating a similar monetised benefit to cost ratio.

8.1.5 At present it has not be possible to undertake a similar monetised analysis for the Westerham option due to the coverage of the transport model. A detail enhancement of the model, to the west in particular, would enable a comparative assessment across all options, as well as moving towards a WebTAG compliant model that will be required to meet later scheme appraisals and funding approval requirements. In the shorter term some treatment of the existing model could be undertaken making use of Census Outputs Areas and Journey to Work to disaggregate zones. Such expansion may also be useful to consider other options, including, for example at Dunton Green, as well as identifying in more detail the transport impacts of the existing options considered to date.

8.1.6 The additional network capacity will generate wider benefits than just to the transport networks. Improved capacity and resulting accessibility will provide the potential to support development growth. The increasing emphasis on transport to facilitate additional housing and employment growth is helpful for supporting the case for investment with methodologies now becoming established to assessing the benefits.

8.1.7 Our review of the case for development support has included dependent housing and commercial sites, direct employment impacts, and greater labour market integration.

8.1.8 An economic value of ‘dependent’ housing developments can now be included in the wider appraisal for transport investments where the transport scheme enables additional residential development to take place that would not take place without the scheme. This is termed dependent development. The land value uplift associated with

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this dependent development is counted as a benefit within the appraisal. It is clear that, at present, there is a scarcity of major housing sites in the Sevenoaks, Tonbridge & Malling, Tunbridge Wells areas that could accommodate any significant development volumes and that could be considered well enough developed in planning terms to be eligible for a dependent housing appraisal.

8.1.9 However, whilst there may be some sites that could be considered as ‘emerging’, these have no status beyond that of a ‘Call for Sites’ exercise, with local authorities such as Tonbridge & Malling undertaking an assessment, concurrent with this study, to examine whether the locations identified have any development potential based on their suitability, availability and achievability during the current Local Plan period.

8.1.10 An analysis of the potential value of a hypothetical ‘dependent’ development, for example, a large scale development of say approximately 2,500 housing units, suggests that, providing a ‘dependency case’ can be made, then the value of these benefits could be around £70m (PV in 2010 prices).

8.1.11 These are potentially large benefits and of a potential magnitude that could fundamentally change the value for money assessment of the slip road options. Therefore whilst no major sites are available or well enough developed in planning terms at the present time, it is suggested that the scope for enabling housing be kept under review as part of the overall planning process, with a view to making a more positive case for improved motorway access sometime in the future.

8.1.12 In any on-going work to develop their Local Plans it is suggested that Sevenoaks and Tonbridge & Malling both carefully consider all potential major development sites and connectivity to both the public transport and highway networks, examining in detail their impacts on the capacity of the transport network and the potential for new infrastructure to enable additional development quantum and densities, as well as earlier delivery programmes. Such work could be undertaken using strategic or more local modelling tools (such as an expanded version of the model used in this assessment), and backed up by enhanced technical work on potential land value uplifts. The resulting assessments could point to a stronger development-led support for major infrastructure proposals than has been established for the east-facing slips based on current development expectations working their way through the planning system.

8.1.13 In respect of employment land, there are few potential sites available and pressure exists to convert sites from employment to residential use to meet housing targets. Our assessment suggests that better access to the M26 would have little impact on the demand for employment land in Tonbridge & Malling or Sevenoaks. However, east- facing slips around Westerham could support larger scale development over the Kent county boundary at Biggin Hill and the Moorhouse/Redland Tile Works sites, both developments are, however, subject to planning consents being granted.

8.1.14 Overall, there appears to be an economic case for investment in the east-facing slip roads, but this is relatively weak, and with some key risks around scheme costs. The case as it stands relies largely on monetised transport benefits arising from journey time savings and reductions in accidents, alongside some modest localised environmental and other amenity benefits for residents living in the A25 corridor. Due to the lack of

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any significant housing developments in the area, at least sufficiently developed in planning terms, the scale of any monetised wider economic benefits will be limited.

8.1.15 The study has reported on an initial consultation with the relevant local authorities, suggesting a range of responses from guarded support to local opposition, with some awaiting indications of potential performance from this study. Further consultation is clearly required if the proposals are to be developed further, and we suggest this is done in a structured way through a consultation strategy, particularly given some apparent opposition to the proposals, especially for residents and landowners in locations immediately adjacent to the new slip road locations.

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APPENDIX A: ANALYSIS OF LABOUR MARKET INTEGRATION

The analysis of labour market integration used a model to predict car driver trips between origins and destinations in Kent. The model specification that provides the best representation of the factors that underlie travel to work decisions was: 푃푖 ∗ 퐽푗 푇푖푗 = 퐾 ∗ [ ] 퐽푖 ∗ 푡푛 Where  푇푖푗 is all trips between i and j with origin I and destination j (that is, in one direction only)  K is a constant  n is a variable applied to t, the journey time, to yield a deterrence function  Pi and Pj are working age populations in i and j respectively  Ji and Jj are jobs in i and j respectively.

Travel to work between locations was considered using the flows in each direction separately. The underlying logic is that differences in the number of jobs between an origin area and a destination area and the travel time will affect the proportion of the working age population that will travel out of the area of residence in order to work. Therefore actual numbers travelling in one direction depends upon the size of the working age population in the area of origin, the number of jobs in each destination area and the travel impedance. Thus more jobs in an external area relative to local jobs would be expected to increase travel outwards, while a larger travel impedance would tend to reduce travel outwards.

An analysis of travel to work by car (as car driver) was undertaken using finely grained geographic areas around Tonbridge & Malling, Sevenoaks, Tunbridge Wells, Medway and Maidstone, and less finely grained areas across the remainder of Kent. Several model specifications were tested, all of which used a combination of data on working age population and a proxy for jobs obtained from the travel to work data.

The analysis was undertaken for all of Kent, but did not include London, the rest of the South East or rest of UK. For rest of South East and rest of UK it is impossible to assign a travel time and therefore it was decided not to include these.

The final version of the model estimated different values of K and n for rural and urban areas, which provided a better fit between actual and predicted trips than applying single values across the whole region.

Appendix Table A 1 shows occupations of residents and Appendix Table A 2 shows residents’ qualifications and earnings. There is a marked difference between Sevenoaks and Maidstone in terms of the proportions of workers engaged in management and professional occupations, which tend to be among the highest paid jobs and which tend to be concentrated in large urban areas. This is reflected in residents’ earnings, shown in Appendix Table A 2: qualifications and earnings of residents . The proportion of residents who possess higher level qualifications (NVQ 3, 4 and above) is also markedly different, which is consistent with both the occupations and earnings data.

In contrast, as shown in Appendix Table A 3, median workplace earnings are quite similar in both Sevenoaks and Maidstone, at least for male full time workers, while median earnings for full-time female workers is somewhat higher in Sevenoaks. However, (median) earnings of both male and female full-time workers are markedly below those of the South East region. The difference between local and South East earnings could be expected to provide an incentive to travel to better-paid (more productive) jobs, which are chiefly located within the London conurbation. Finally, differences in workplace earnings cannot readily be explained by differences in employment structure: a more detailed breakdown of the employment categories shown in Appendix Table A 3 would be required in order to explore the role of employment structure.

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Appendix Table A 1: occupations of residents

OCCUPATIONS Sevenoaks Maidstone South East July 2014-June 2015 % % % Soc 2010 Major Group 1-3 60.3 47.0 49.4 Managers, directors & senior officials 14.4 11.5 11.8 Professional occupations 30.2 16.7 21.5 Associate professional & technical 15.7 18.8 15.8 Soc 2010 Major Group 4-5 18.5 25.3 21.1 Administrative & secretarial 8.2 10.6 10.7 Skilled trades occupations 10.3 14.8 10.4 Soc 2010 Major Group 6-7 10.3 11.9 15.6 Soc 2010 Major Group 8-9 10.9 15.7 13.9 Source: NOMIS Local Authority Profiles

Appendix Table A 2: qualifications and earnings of residents

QUALIFICATIONS Sevenoaks Maidstone South East Jan-Dec 2014 %of resident population aged 16-64 % % % NVQ4 and above 41 31.2 39.1 NVQ3 25.1 21.8 21.4 NVQ2 11.5 21.4 16.6 NVQ1, other or no qualifications 22.4 25.6 22.9

EARNINGS OF RESIDENTS Sevenoaks Maidstone South East 2015 All full-time workers £ 595.50 £ 555.70 £ 574.90 Male full-time workers £ 651.00 £ 599.00 £ 626.50 Female full-time workers £ 559.50 £ 481.80 £ 499.50 Source: NOMIS Local Authority Profiles

M25 M26 Connectivity Economic Case Study 103712 Final Report 21/06/2016 Page 80/83

Appendix Table A 3: workplace earnings and employment structure

EARNINGS BY WORKPLACE Sevenoaks Maidstone South East 2015 gross weekly earnings (median) All full-time workers £ 489.70 £ 499.40 £ 552.10 Male full-time workers £ 553.50 £ 547.30 £ 600.00 Female full-time workers £ 438.80 £ 413.50 £ 484.70

EMPLOYMENT STRUCTURE Sevenoaks Maidstone South East % % % Primary Services (A-B: agriculture and mining) 0.5 0.3 0.2 Energy and Water (D-E) 1.2 0.6 1.1 Manufacturing (C) 6.4 5.8 6.2 Construction (F) 9.9 5.6 4.8 Services (G-S) 82.1 87.8 87.6 Wholesale and retail, including motor trades (G) 17.0 16.4 17.0 Transport storage (H) 2.0 3.8 4.6 Accommodation and food services(I) 7.3 6.9 7.4 Information and communication (J) 4.4 2.8 5.8 Financial and other business services(K-N) 25.2 21.9 22.5 Public admin, education and health (O-Q) 20.0 32.2 25.6 Other Services (R-S) 6.2 3.6 4.8 Source: NOMIS Local Authority Profiles

M25 M26 Connectivity Economic Case Study 103712 Final Report 21/06/2016 Page 81/83

APPENDIX B: TEE, PUBLIC ACCOUNTS AND AMCB TABLES M25/M26 Connectivity: TEE, Public Accounts and AMCB Tables Option 1A Option 1A Option 1A Option 1A Option 1A Option 1A Option 1A Option 1A Option 1A Option 1A Option 2C PB Report Rerun VoT Conv AM, IP Coding Weekend Off-Peak Scheme +15% W'ham Dev Option 2C T0 T1 v Previous T2 v Previous T3 v Previous T4 v Previous T5 v Previous T5a v Previous T5b v Previous T5c v 5 T5e v5b T6b v5b Economic Efficiency of the Transport System(TEE)

Consumer - Commuting user benefits Travel Time 18,797 16,040 -2,757 19,904 3,864 16,728 -3,176 13,649 -3,079 14,310 661 15,136 826 13,649 0 7,977 -7,159 9,222 -5,914 Vehicle operating costs 2,346 204 -2,142 2,478 2,274 3,120 642 2,475 -645 2,621 146 2,804 183 2,475 0 1,472 -1,332 822 -1,982 NET CONSUMER - COMMUTING BENEFITS 21,143 16,244 -4,899 22,382 6,138 19,848 -2,534 16,124 -3,724 16,931 807 17,940 1,009 16,124 0 9,449 -8,491 10,044 -7,896

Consumer - Other user benefits Travel Time 50,836 43,360 -7,476 53,831 10,471 32,439 -21,392 22,253 -10,186 27,565 5,312 34,206 6,641 22,253 0 33,667 -539 19,431 -14,775 Vehicle operating costs 4,889 211 -4,678 5,132 4,921 3,803 -1,329 3,368 -435 4,301 933 5,467 1,166 3,368 0 3,871 -1,596 1,295 -4,172 NET CONSUMER - OTHER BENEFITS 55,725 43,571 -12,154 58,963 15,392 36,242 -22,721 25,621 -10,621 31,866 6,245 39,673 7,807 25,621 0 37,538 -2,135 20,726 -18,947

Business user benefits (Road Personal) Travel Time 48,699 41,559 -7,140 51,569 10,010 32,624 -18,945 24,600 -8,024 29,201 4,601 34,953 5,752 24,600 0 29,331 -5,622 19,783 -15,170 Vehicle operating costs 3,062 1,272 -1,790 3,243 1,971 2,481 -762 1,958 -523 2,369 411 2,882 513 1,958 0 2,056 -826 1,068 -1,814 Subtotal 51,761 42,831 -8,930 54,812 11,981 35,105 -19,707 26,558 -8,547 31,570 5,012 37,835 6,265 26,558 0 31,387 -6,448 20,851 -16,984

Business user benefits (Road Freight) Travel Time 5,754 4,200 -1,554 4,384 184 4,478 94 844 -3,634 941 97 1,062 121 844 0 1,706 644 375 -687 Vehicle operating costs 2,472 3,683 1,211 3,589 -94 3,382 -207 1,262 -2,120 1,660 398 2,157 497 1,262 0 1,140 -1,017 628 -1,529 Subtotal 8,226 7,883 -343 7,973 90 7,860 -113 2,106 -5,754 2,601 495 3,219 618 2,106 0 2,846 -373 1,003 -2,216

Other business Impacts NET BUSINESS IMPACT 59,987 50,714 -9,273 62,785 12,071 42,965 -19,820 28,664 -14,301 34,171 5,507 41,054 6,883 28,664 0 34,233 -6,821 21,854 -19,200 TOTAL Present Value of Transport Economic Efficiency Benefits (TEE) 136,855 110,529 -26,326 144,130 33,601 99,055 -45,075 70,409 -28,646 82,968 12,559 98,667 15,699 70,409 0 81,220 -17,447 52,624 -46,043

Note: In the TEE table benefits appear as positive numbers, while costs appear as negative numbers. Note: All entries are present values discounted to 2010, in 2010 prices.

Public Accounts

Central Government Funding: Transport Investment costs 58,114 58,114 0 58,114 0 58,114 0 58,114 0 58,114 0 58,114 0 66,831 8,717 58,114 0 29,057 -29,057 NET IMPACT 58,114 58,114 0 58,114 0 58,114 0 58,114 0 58,114 0 58,114 0 66,831 8,717 58,114 0 29,057 -29,057

Central Government Funding: Non-Transport Indirect tax revenues 3,025 1,316 -1,709 3,670 2,354 3,303 -367 2,729 -574 3,307 578 4,030 723 2,729 0 2,558 -1,472 1,277 -2,753

TOTALS Broad Transport Budget 58,114 58,114 0 58,114 0 58,114 0 58,114 0 58,114 0 58,114 0 66,831 8,717 58,114 0 29,057 -29,057 Wider Public Finances 3,025 1,316 -1,709 3,670 2,354 3,303 -367 2,729 -574 3,307 578 4,030 723 2,729 0 2,558 -1,472 1,277 -2,753

Note: In the Public Accounts table costs appear as positive numbers, while revenues and developer contributions appear as negative numbers. Note: All entries are present values discounted to 2010, in 2010 prices.

Analysis of Monetised Costs and Benefits

Greenhouse Gases 815 1,267 452 632 -635 1,617 985 1,498 -119 1,275 -223 1,545 270 1,883 338 1,275 0 1,128 -755 644 -1,239 Economic Efficiency: Consumer Users (Commuting) 21,143 16,244 -4,899 22,382 6,138 19,848 -2,534 16,124 -3,724 16,931 807 17,940 1,009 16,124 0 9,449 -8,491 10,044 -7,896 Economic Efficiency: Consumer Users (Other) 55,725 43,571 -12,154 58,963 15,392 36,242 -22,721 25,621 -10,621 31,866 6,245 39,673 7,807 25,621 0 37,538 -2,135 20,726 -18,947 Economic Efficiency: Consumer Users (All) 56,360 76,868 20,508 59,815 -17,053 81,345 21,530 56,090 -25,255 41,745 -14,345 48,797 7,052 57,613 8,816 41,745 0 46,987 -10,626 30,770 -26,843 Economic Efficiency: Business Users and Providers 62,205 59,987 -2,218 50,714 -9,273 62,785 12,071 42,965 -19,820 28,664 -14,301 34,171 5,507 41,054 6,883 28,664 0 34,233 -6,821 21,854 -19,200 Wider Public Finances (Indirect Taxation Revenues) -3,025 -1,316 1,709 -3,670 -2,354 -3,303 367 -2,729 574 -3,307 -578 -4,030 -723 -2,729 0 -2,558 1,472 -1,277 2,753 Present Value of Benefits (PVB) 119,380 135,097 15,717 109,845 -25,252 142,077 32,232 97,250 -44,827 68,955 -28,295 81,206 12,251 96,520 15,314 68,955 0 79,790 -16,730 51,991 -44,529

Broad Transport Budget 53,529 58,114 4,585 58,114 0 58,114 0 58,114 0 58,114 0 58,114 0 58,114 0 66,831 8,717 58,114 0 29,057 -29,057 Present Value of Costs (PVC) 53,529 58,114 4,585 58,114 0 58,114 0 58,114 0 58,114 0 58,114 0 58,114 0 66,831 8,717 58,114 0 29,057 -29,057 M25 M26 Connectivity OVERALL IMPACTS Net Present Value (NPV) Economic65,851 76,983 Case Study11,132 51,731 -25,252 83,963 32,232 10371239,136 -44,827 10,841 -28,295 23,092 12,251 38,406 15,314 2,124 -8,717 21,676 -16,730 22,934 -15,472 Benefit to Cost Ratio (BCR) 2.23 2.32 0.09 1.89 -0.43 2.44 0.55 1.67 -0.77 1.19 -0.49 1.40 0.21 1.66 0.26 1.03 -0.15 1.37 -0.29 1.79 0.13 Note: This table includes costs and benefits which are regularly or occasionally Finalpresented Report in monetised form in transport appraisals, together with some where monetisation is21/06/2016 in prospect. There may also be other Page 82/83 significant costs and benefits, some of which cannot be presented in monetised form. Where this is the case, the analysis presented above does NOT provide a good measure of value for money and should not be used as the sole basis for decisions.

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