BRIDGWATER TRANSPORT OPTIONS INFRASTRUCTURE OPTIONS TECHNICAL REPORT

October 2016 BRIDGWATER TRANSPORT OPTIONS INFRASTRUCTURE OPTIONS TECHNICAL REPORT Somerset County Council

Project no: 62102386

Date: October 2016

WSP | Parsons Brinckerhoff Riverside Chambers Castle Street Taunton TA1 4AP www.wsp-pb.co.uk iv

TABLE OF CONTENTS

EXECUTIVE SUMMARY ...... 1

1 PROJECT BACKGROUND ...... 1 1.1 Introduction ...... 1 1.2 Model History ...... 1 1.3 COntext ...... 1 1.4 STUDY OBJECTIVES ...... 2

2 FORECAST DEMAND ...... 3 2.1 Model overview...... 3 2.2 Demand Forecast Methodology ...... 3 2.3 Trip Generation...... 4 2.4 Background Growth ...... 7 2.5 HGV Growth ...... 7 2.6 Distribution ...... 7 2.7 Highway Assignment ...... 8

3 INFRASTRUCTURE SCENARIOS ...... 9 3.1 Do Minimum infrastructure ...... 9 3.2 Do something infrastructure ...... 9

4 ASSIGNMENT RESULTS ...... 11 4.1 Forecast Scenarios ...... 11 4.2 ASSIGNMENT Convergence ...... 11 4.3 Network Wide Statistics ...... 12 4.4 Journey time analysis ...... 14 4.5 DO Minimum Scenario - Traffic Impacts ...... 15 4.6 Do Something Northern Bypass – Traffic Impacts ...... 18 4.7 Do Something Eastern distributor road – Traffic Impacts ...... 22 4.8 Do Something Southern bypass – Traffic Impacts ...... 28 4.9 DO SOMETHING All Options combined – Traffic Impacts ...... 33

5 CONCLUSION ...... 41 5.1 Summary of process ...... 41 5.2 Summary of Findings ...... 41 5.3 Limitations ...... 42 5.4 Further work ...... 43

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TABLES

TABLE 2-1: PROPOSED DEVELOPMENTS – TRIP GENERATION (PCU) ...... 6 TABLE 2-2: MOTORWAY SERVICES AREA TRIPS ...... 6 TABLE 4-1: WEBTAG CONVERGENCE CRITERIA ...... 11 TABLE 4-2: JOURNEY ROUTES START AND END POINTS ...... 15 TABLE 4-3: JUNCTIONS WHICH ARE OVERCAPACITY IN THE DO MINIMUM SCENARIO ...... 16 TABLE 4-4: OVERCAPACITY JUNCTIONS IN THE DO SOMETHING NORTHERN BYPASS OPTION ...... 20 TABLE 4-5: JOURNEY TIME RESULTS FOR NORTHERN BYPASS DO SOMETHING SCENARIO AND ALTERNATIVE ROUTE ...... 22 TABLE 4-6: OVERCAPACITY JUNCTIONS IN THE DO SOMETHING EASTERN DISTRIBUTOR ROAD OPTION SCENARIO ...... 25 TABLE 4-7: JOURNEY TIME RESULTS FOR EASTERN DISTRIBUTOR ROAD SCENARIO AND ALTERNATIVE ROUTE 1 ...... 27 TABLE 4-8: JOURNEY TIME RESULTS FOR EASTERN DISTRIBUTOR ROAD SCENARIO AND ALTERNATIVE ROUTE 2 ...... 28 TABLE 4-9: OVERCAPACITY JUNCTIONS IN THE DO SOMETHING SOUTHERN BYPASS OPTION SCENARIO ...... 31 TABLE 4-10: JOURNEY TIME RESULTS FOR SOUTHERN BYPASSS SCENARIO AND ALTERNATIVE ROUTE ...... 32 TABLE 4-11: OVERCAPACITY JUNCTIONS IN THE DO SOMETHING ALL INFRASTRUCTURE OPTION COMBINED SCENARIO...... 35 TABLE 4-12: NORTHERN BYPASS AND ALTERNATIVE ROUTE JOURNEY TIME RESULTS ...... 37 TABLE 4-13: EASTERN DISTRIBUTOR ROAD AND FIRST ALTERNATIVE ROUTE JOURNEY TIME RESULTS...... 38 TABLE 4-14: EASTERN DISTRIBUTOR ROAD AND SECOND ALTERNATIVE ROUTE JOURNEY TIME RESULTS...... 39 TABLE 4-15: SOUTHERN BYPASS AND ALTERNATIVE ROUTE JOURNEY TIME RESULTS ...... 40 TABLE 5-1: MAIN INFRASTRUCTURE RESULTS - INDIVIDUAL ASSESSMENT...... 42

FIGURES

FIGURE 2-1: PROCESS TO CREATE DEMAND MATRICES ...... 4 FIGURE 2-2: DEVELOPMENT SITE LOCATIONS USED IN INFRASTRUCTURE TESTING ...... 5 FIGURE 3-1: LOCATION OF PROPOSED INFRASTRUCTURE ...... 10 FIGURE 4-1: TOTAL TRAVEL TIME (PCU HR)...... 12 FIGURE 4-2: AVERAGE SPEED (KPH) ...... 13 FIGURE 4-3: AVERAGE SPEED IN BRIDGWATER (KPH) ...... 14

Bridgwater Transport Options - Infrastructure Options Technical Report WSP | Parsons Brinckerhoff Somerset County Council Project No 62102386 vi

FIGURE 4-4: JOURNEY ROUTES ...... 15 FIGURE 4-5: JUNCTIONS TO BE OVERCAPACITY IN THE DO MINIMUM SCENARIO.. 17 FIGURE 4-6: ACTUAL FLOW DIFFERENCE BETWEEN DS - NORTHERN BYPASS OPTION AND DM - AM ...... 18 FIGURE 4-7: ACTUAL FLOW DIFFERENCE BETWEEN DS - NORTHERN BYPASS OPTION AND DM - PM ...... 19 FIGURE 4-8: LOCATION PLAN FOR NORTHERN BYPASS OPTION ...... 21 FIGURE 4-9: ACTUAL FLOW DIFFERENCE BETWEEN DS - EASTERN DISTRIBUTOR ROAD OPTION AND DM - AM...... 24 FIGURE 4-10: ACTUAL FLOW DIFFERENCE BETWEEN DS - EASTERN DISTRIBUTOR ROAD OPTION AND DM - PM...... 24 FIGURE 4-11: LOCATION PLAN FOR EASTERN DISTRIBUTOR ROAD OPTION ...... 26 FIGURE 4-12: ACTUAL FLOW DIFFERENCE BETWEEN DS - SOUTHERN BYPASS OPTION AND DM - AM ...... 29 FIGURE 4-13: ACTUAL FLOW DIFFERENCE BETWEEN DS - SOUTHERN BYPASS OPTION AND DM - PM ...... 30 FIGURE 4-14: LOCATION PLAN FOR SOUTHERN BYPASS OPTION...... 31 FIGURE 4-15: ACTUAL FLOW DIFFERENCE BETWEEN DS - ALL INFRASTRUCTURE OPTION AND DM - AM ...... 33 FIGURE 4-16: ACTUAL FLOW DIFFERENCE BETWEEN DS - ALL INFRASTRUCTURE OPTION AND DM - PM ...... 34 FIGURE 4-17: LOCATION PLAN FOR ALL INFRASTRUCTURE OPTION ...... 36

APPENDICES

APPENDIX A CONVERGENCE RESULTS APPENDIX B DO SOMETHING SCENARIO - NORTHERN BYPASS OPTION SELECT LINK ANALYSIS APPENDIX C DO SOMETHING SCENARIO - EASTERN DISTRIBUTOR ROAD OPTION SELECT LINK ANALYSIS APPENDIX D DO SOMETHING SCENARIO – SOUTHERN BYPASS OPTION SELECT LINK ANALYSIS APPENDIX E DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION SELECT LINK ANALYSIS

Bridgwater Transport Options - Infrastructure Options Technical Report WSP | Parsons Brinckerhoff Somerset County Council Project No 62102386 EXECUTIVE SUMMARY

Based on a single demand scenario (based on potential Local Plan allocations) this study identifies the potential traffic benefit of constructing additional infrastructure around Bridgwater. Four potential infrastructure scenarios have been considered: a Northern Bypass; an Eastern Distributor Road; a Southern Distributor Road only; and implementation of all three infrastructure options.

As would be expected, the implementation of all three infrastructure options in combination provided the greatest improvement to traffic by all measures considered within this report.

Of the individual scenarios, the Northern Bypass and the Southern Bypass scenarios have very similar network wide improvements compared to the Do Minimum scenario. However the Southern Bypass scenario generally benefits local traffic whilst the Northern Bypass and Eastern Distributor Road scenarios mainly benefit longer distance through traffic.

The Eastern Distributor Road scenario has the least traffic benefit when assessed against all measures considered in this report, with the exception of the demand attracted to it.

This was a high level assessment, making broad assumptions in relation to the nature of the developments and access arrangements. It does not replace the requirement for a detailed and robust Transport Assessment supporting any future planning applications, and nor does it guarantee that any proposals would be acceptable to the Highway Authority. It is important to emphasise that this assessment focuses only on traffic impact and that a full appraisal would cover environmental and social impacts.

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1 PROJECT BACKGROUND 1.1 INTRODUCTION

1.1.1 WSP | Parsons Brinckerhoff has been commissioned by Somerset County Council (SCC) to undertake traffic modelling in relation to the formulation and assessment of Transport Options for Bridgwater on behalf of Sedgemoor District Council (SDC). The outcome of this study will ultimately be used as part of the evidence base for the upcoming Local Plan (Core Strategy Review) to be developed by SDC.

1.1.2 This report outlines the finding of the bypass option testing, undertaken using the adapted TSTM3 SATURN Traffic Model. The process of creating these adapted forecast models was described in the ‘Bridgwater Transport Options – Forecast Report’, dated March 2016.

1.2 MODEL HISTORY

1.2.1 Forecasts of traffic demand have been prepared in accordance with the Department for Transport’s WebTAG guidance. Due to the nature of the existing traffic model, it does not meet all WebTAG criteria. However, the model is considered appropriate for this high level strategy work.

1.2.2 The original Taunton Strategic Traffic Model (TSTM1) was built in 2001 and has since been updated and revalidated, most recently to a 2010 base year (TSTM3). An extended version of the model was developed in 2012 in order to test the impact of the Huntspill Energy Park development (HEP). This expanded version, which maintains the 2010 base year, is the one which has been used for the current work.

1.2.3 The 2010 TSTM3 covered the towns of Bridgwater, Taunton and Wellington, including the M5 between Junctions 23 and 26. The expanded 2012 version of the model that was developed to test HEP also includes network further to the north and east, as far as Junction 22.

1.2.4 Primary routes and important minor roads are included and fully simulated within the fully modelled area. Peripheral parts of the network are coded as a ‘buffer network’.

1.3 CONTEXT

1.3.1 The ‘Bridgwater Transport Options – Forecast Report’ described the potential impact to Bridgwater’s traffic network, highlighting key junctions affected by the core scenario developments as well as five proposed development sites. Proposed growth in Bridgwater is expected to impact junctions on all key routes through the town centre, particularly along:

· A38 Bristol Road · A39 Quantock Road · Homberg Way / Western Way.

1.3.2 Following on from the first report, current work seeks to identify suitable large scale infrastructure to support the development sites.

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1.4 STUDY OBJECTIVES

1.4.1 The objective of this study is to identify the effectiveness of four proposed infrastructure options in accommodating increased travel demand as a result of the proposed Local Plan allocations. The four infrastructure options are described in Chapter 3: Infrastructure Scenarios.

1.4.2 All infrastructure scenarios will be based upon a single demand scenario as described in Chapter 2: Forecast Demand.

1.4.3 This technical report outlines the detailed demand, infrastructure and methodology assumptions used in undertaking this transport based analysis. It also demonstrates the benefit of each of the four scenarios in comparison to a Do Minimum scenario with no infrastructure improvements.

1.4.4 It is noted that this document is intended to be a technical report. A non-technical summary report will be produced on completion of this project.

1.4.5 The remainder of this report is set out as follows:

à Chapter 2: Forecast Demand – outlines the process which has been adopted to create the forecast demand and specifies the assumptions made at each stage à Chapter 3: Infrastructure Scenarios – describes the infrastructure options which have been considered in this study à Chapter 4: Assignment Results – describes the future year conditions in terms of predicted traffic flows and delay for links and junctions for each scenario à Chapter 5: Conclusion – summarises the key findings

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2 FORECAST DEMAND 2.1 MODEL OVERVIEW

2.1.1 The base model was created to represent a typical weekday during term time in 2010 and consists of an AM peak (08:00 to 09:00) and PM peak (17:00 to 18:00).

2.1.2 Demand in the model is split into two user classes which represent ‘light’ and ‘heavy’ vehicles. In addition, buses are represented as fixed flows on timetabled routes. The existing user classes have been taken forward to model forecasting, with bus routes assumed to remain unchanged.

2.1.3 Unless otherwise stated, all assumptions are as set out in the ‘Bridgwater Transport Options – Forecast Report’, dated March 2016.

2.2 DEMAND FORECAST METHODOLOGY

2.2.1 The existing Sedgemoor District Council Core Strategy ‘Shaping the Future of Sedgemoor 2006-27’ runs to 2027. The revised Local Plan will cover the period up to 2032. The modelled forecast year has been assumed as 2032 to include agreed developments from both documents. All forecasting years were previously tested in 'Bridgwater Transport Options – Forecast Report’.

2.2.2 One demand scenario has been produced for each time period (AM and PM). This demand scenario is identical for the Do Minimum scenario and each Do Something scenario.

2.2.3 The flow chart in Figure 2-1 below summarises the steps involved in the preparation of the forecast year demand matrices. Each step is described in more detail throughout this chapter.

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Figure 2-1: Process to create demand matrices

1 - Trip • To determine the total traffic flow to/from Generation each explicitly modelled development site.

2 - Background • To determine growth factors to be applied to Growth trips associated with non-development zones.

3 - HGV • To determine the growth factors to be applied to HGV trips associated with non-development Growth zones.

• To determine the distribution of traffic to, 4 - Distribution from and between explicitly modelled development sites.

5 - Highway • To assign the forecast demand matrices onto the forecast network using the highway Assignment assignment software SATURN.

2.3 TRIP GENERATION

2.3.1 Nine potential demand scenarios were tested and discussed in the ‘Bridgwater Transport Options – Forecast Report’, dated March 2016. This included five development sites and a further four combinations of at least two sites. As a result of this analysis, a single demand scenario was agreed for testing within this study.

2.3.2 The demand scenario taken forward includes all committed and proposed development within Sedgemoor up to the end of the Core Strategy Period, and is based on an Uncertainty Log (provided in Appendix B of the ‘Bridgwater Transport Options – Forecast Report’, dated March 2016). Additionally, the proposed sites 1, 2, 4, and 5 are included as illustrated in Figure 2-2.

2.3.3 In the previous report, our work included site 3; it has been excluded from this report as SDC now consider it to be unrealistic to promote this site at this time.

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Figure 2-2: Development Site Locations Used In Infrastructure Testing

2.3.4 The make-up of each development site is based upon the assumptions discussed in Section 1.2 of the ‘Bridgwater Transport Options – Forecast Report’. These have however been updated for this assessment based upon discussion with SDC as follows.

à Site 1 - Land to the west of Bridgwater – 1,200 dwellings, primary school and the relocation of Haygrove School with two accesses; à Site 2 - Land at East Bridgwater – 1,200 dwellings and a primary school; à Site 4 - Land at South Bridgwater – 30,000m2 B1 development; à Site 5 - Land at Huntworth – 5,338m2 B1 development and 22,257m2 B8 development. Additionally, this site includes a proposed updated motorway services area (MSA).

2.3.5 The resultant total trip generation is shown in Table 2-1. Note that there are assumed to be no trips to or from the relocated Haygrove School during the PM peak.

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Table 2-1: Proposed developments – trip generation (pcu)

PROPOSED AM AM PM PM DEVELOPMENT ARRIVALS DEPARTURES ARRIVALS DEPARTURES Site 1 – Land to the West of Bridgwater 414 657 468 271

Site 2 – Land to the East of Bridgwater 195 512 468 271

Site 4 – Land at South Bridgwater 434 49 52 337

Site 5 – Land at Huntworth 728 626 618 714

2.3.6 The improved Motorway Service Area trips, as part of site 5, have been estimated using Highways England’s TRADS database. Similar MSA sites have been identified (such as Stafford MSA) to inform expected demand for site 5. It has been assumed that the origin and destination trips are equal, as MSA trips are generally short stay. The resultant demand is presented in Table 2-2.

Table 2-2: Motorway Services Area trips VEHICLE TYPE AM AM PM PM (VEHICLES) (PCU) (VEHICLES) (PCU) HGVs 113 226 118 236 Light Vehicles 353 353 345 345 Total Vehicles 466 579 463 581 HGV % 24% - 25% -

2.3.7 It has been assumed that trips to and from the MSA are diverted from existing trips on the M5. These trips were merely rerouted to use the roundabout at M5 J24 to visit the services, and then leave to continue their journey soon after.

2.3.8 The Impact of promoting sustainable travel was not accounted for in this assessment. As such, mode choice is considered to be consistent with the base modelling. Some of the impacts described in this report could be partially mitigated through the implementation of the emerging Local Plan.

HGV TRIPS

2.3.9 For most development it has been assumed that all explicitly modelled trips will be ‘light’ vehicles with HGV trips accounted for as part of background growth. The exception is for larger development sites and the MSA, where trip generation for HGVs has been taken from the relevant TA or detailed analysis.

2.3.10 More details about the Uncertainty Log, trip rates and the source used to establish the trip generation for each site is provided in the ‘Bridgwater Transport Options – Forecast Report’, dated March 2016.

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2.4 BACKGROUND GROWTH

2.4.1 Background traffic growth has been applied to traffic associated with non- development zones by obtaining growth factors from TEMPRO (dataset 6.2)1. Background traffic growth was not applied to new development zones which contained point-loaded trips. More details about this is provided in the ‘Bridgwater Transport Options – Forecast Report’, dated March 2016.

2.5 HGV GROWTH

2.5.1 Growth factors for HGV vehicles were determined using the Department for Transport’s Road Traffic Forecasts 2015 (RTF)2. More details about this are provided in the ‘Bridgwater Transport Options – Forecast Report’, dated March 2016.

2.6 DISTRIBUTION

2.6.1 A gravity model was developed to derive a trip distribution for all development sites. In general a similar methodology has been used to that described in the ‘Bridgwater Transport Options – Forecast Report’, dated March 2016. However, Box- Cox deterrence function rather than the Logit-Kirchhoff deterrence function used in the previous modelling.

2.6.2 The Box-Cox deterrence function is defined as follows:

C 1 f C = exp − Where:

α and β are parameters which were calibrated; and C represents the generalised cost between zones i and j.

2.6.3 Trip distribution was of particular importance for this assessment, as a minor change will greatly affect the amount of users who benefit from the proposed infrastructure schemes.

2.6.4 In general, longer distance trips will usually have greater variability than shorter distance trips, purely due to their magnitude. When used in combination with a logarithmic distance scale, the Box-Cox deterrence function accounts for the non- consistent variance of trip length. The trip length distribution is effectively transformed from a short-distance skewed distribution to better represent a normal distribution. As such, short-distance trips become more significant when weighting the distribution, producing improved calibration in the vicinity of Bridgewater.

1 TEMPRO Growth was only applied to ‘light’ vehicles (i.e. cars) as HGV growth was applied separately 2 Factors were calculated based upon the RTF ‘Scenario 1’ assumptions.

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2.7 HIGHWAY ASSIGNMENT

2.7.1 The demand matrix was assigned onto the forecast network using the highway assignment modelling software SATURN (v.10.9.22). The model was assigned using link-based assignment which is consistent with the original 2010 base model and all forecasting scenarios previously created for the ‘Bridgwater Transport Options – Forecast Report’, dated March 2016.

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3 INFRASTRUCTURE SCENARIOS 3.1 DO MINIMUM INFRASTRUCTURE

3.1.1 Committed infrastructure, including that which has been constructed since 2010, has been included in the 2032 forecast network. After discussion with Highways England, it was agreed that the proposed Henlade Bypass, improvements to M5 Junction 25 and improvements to the A358 will also be included in the 2032 forecast model, as Government policy deems these to be committed. Other committed infrastructure is described in more detailed in the ‘Bridgwater Transport Options – Forecast Report’. The most significant schemes include:

à Northern Inner Distributor Road in Taunton à Junction improvements associated with Hinkley Point C à Colley Lane Link Road in Bridgwater à Henlade Bypass

3.1.2 Appendix A of the ‘Bridgwater Transport Options – Forecast Report’, dated March 2016, includes the Method Statement that was agreed for this project. Paragraph 4.10 portrays SDC’s initial intentions on infrastructure testing. Further discussions after the first report had been undertaken and the preferred option for testing of potential mitigation has given rise to a new preferred scenario. As a result, the infrastructure included in the Do Minimum scenario includes a second access roundabout to preferred development site 1 and an updated two lane layout at the A39 Quantock Road westbound that leads to the second access onto the site.

3.2 DO SOMETHING INFRASTRUCTURE

3.2.1 Three potential infrastructure improvement options have been proposed by SDC to be considered in the Do Something scenarios. These options are illustrated in Figure 3-1 and are described as below:

à Northern Bypass: Links Dunball Roundabout to the A39/Quantock Road/Sandford Hill junction. This has been assumed to be a single-lane carriageway at 60 mph. à Eastern Distributor Road: Consists of two key sections, both assumed as 30 mph single carriageway. The first section consists of speed and capacity improvements to the existing Bower Lane. The second section links Westonzoyland Road to Colley Lane Southern Access Road via the low lying meads area. à Southern Bypass: Links Huntworth Roundabout to the Spaxton Road/Enmore Road junction, then on to the A39 via Spaxton Road. The alignment has been assumed to follow parts of the existing Durleigh Road and Campion Way. The road is assumed to be a single-lane carriageway at 60 mph.

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Figure 3-1: Location of Proposed Infrastructure

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4 ASSIGNMENT RESULTS 4.1 FORECAST SCENARIOS

4.1.1 This chapter summarises the assignment results for each of the forecast assignments in terms of the network-wide statistics, journey times and the main traffic impacts associated with the following four scenarios:

A. Northern Bypass only

B. Eastern Distributor Road only

C. Southern Distributor Road only

D. Implementation of all three infrastructure options.

4.2 ASSIGNMENT CONVERGENCE

4.2.1 Model convergence is required in order to provide stable, consistent and robust model results and to differentiate between real changes due to the assessment scheme and those associated with modelling noise. The WebTAG specified convergence criteria and acceptability levels for each criterion are summarised in Table 4-13.

Table 4-1: WebTAG Convergence Criteria MEASURE OF CONVERGENCE BASE MODEL ACCEPTABLE VALUES Delta and %GAP Less than 0.1% or at least stable with convergence fully documented and all other criteria met Percentage of links with flow Four consecutive iterations greater than 98% change (P)<1% Percentage of links with cost Four consecutive iterations greater than 98% change (P2)<1% Percentage change in total Four consecutive iterations less than 0.1% (Stochastic User user costs (V) Equilibrium only)4

4.2.2 Appendix A provides the results for all modelled scenarios in more details. The results demonstrate that the all models meet the criteria specified by WebTAG and it is therefore considered that the all modelled scenarios have achieved a satisfactory level of convergence.

3 From Table 4, WebTAG Unit M3.1 (January 2014) 4 This criteria has not been considered for this model as is only applicable to Stochastic User Equilibrium Assignment (SUE)

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4.3 NETWORK WIDE STATISTICS

4.3.1 The network-wide statistics reflect expected changes due to traffic re-routing in each forecast year and the impact of the schemes upon journey lengths and travel times. They also provide an indication of the anticipated impact this would have on the average traffic speeds.

4.3.2 The main results for the network wide statistics for total travel time and average speed are presented from Figure 4-1 to Figure 4-3 for both AM and PM peaks, in each modelled scenario.

4.3.3 Note that in each case,

à DM denotes Do Minimum; à DS denotes Do Something (i.e. Development but no additional infrastructure); à NO denotes Northern Bypass option; à EO denotes Eastern Distributor Road option; à SO denotes Southern Bypass option; à 3O denotes all infrastructure options together.

Figure 4-1: Total Travel Time (pcu hr)

Total Travel Time in Bridgwater 5,000 s r 4,500 u o H u

c 4,000 P

3,500 DM DS NO DS EO DS SO DS 3O DM DS NO DS EO DS SO DS 3O Scenario

Total Travel Time in Bridgwater (pcu hr) - AM Total Travel time in Bridgwater (pcu hr) - PM

4.3.4 Total Travel Time in Bridgwater was calculated using the link cruise time and actual flow on the link. Figure 4-1 demonstrates that the total travel time decreases in the Do Something scenarios compared to the Do Minimum scenario for both time periods. The Eastern option scenario has the least impact. In the case of including all infrastructure options, total journey times decrease by approximately 16% for all journeys within Bridgwater.

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Figure 4-2: Average Speed (kph)

Average Speed 60 r u o h r e p s

r 55 e t e m o l i K 50 DM DS NO DS EO DS SO DS 3O DM DS NO DS EO DS SO DS 3O Scenario

Average Speed (overall kph) - AM Average Speed (overall kph) - PM

4.3.5 Figure 4-2 reveals that average speed generally increases in the Do Something scenarios compared to the Do Minimum scenario. This figure clearly shows that the average speed is the highest in the scenarios where all three infrastructure options are being tested, reaching 58 kph in the AM and 55 kph in the PM period.

4.3.6 The wider modelled network includes Bridgwater, Taunton and other external areas. To gain a more detailed understanding of the impact specifically in Bridgwater, the average speed in this area has been analysed separately as shown in Figure 4-3. The area extends from Cannington to Westonzoyland and Puriton Villages.

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Figure 4-3: Average Speed in Bridgwater (kph)

Average Speed 41 r u o

h 40 r e p s

r 39 e t e

m 38 o l i K 37 DM DS NO DS EO DS SO DS 3O DM DS NO DS EO DS SO DS 3O Scenario

Average Speed (overall kph) - AM Average Speed (overall kph) - PM

4.3.7 Figure 4-3 above indicates that the average speed in Bridgwater increases in all Do Something scenarios. Most significantly, this increase is up to 2 kph with the inclusion of three infrastructure options.

4.4 JOURNEY TIME ANALYSIS

4.4.1 Journey time analysis has been undertaken on the Do Something scenarios to compare most used alternative routes to each of the infrastructure options. The alternative routes were determined by observing origins and destinations for people using each infrastructure option. The location of each route is shown below in Figure 4-4.

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Figure 4-4: Journey Routes

4.4.2 A description of each route and the location of the start and end points is provided in Table 4-2

Table 4-2: Journey Routes start and end points JOURNEY DIRECTION START POINT END POINT ROUTE

NB Showground Road/Marsh Lane A39 Puriton Hill / Bath Road JR1 and JR2 SB A39 Puriton Hill / Bath Road Showground Road/Marsh Lane NB Showground Road/Marsh Lane A372 Westonzoyland Road JR3 and JR4 SB A372 Westonzoyland Road Showground Road/Marsh Lane NB A39 Quantock Road/ Sandford Hill Dunball Roundabout JR5 and JR6 SB Dunball Roundabout A39 Quantock Road/ Sandford Hill NB Huntworth Roundabout A39 Quantock Road/ Sandford Hill JR7 and JR8 SB A39 Quantock Road/ Sandford Hill Huntworth Roundabout

4.4.3 Each set of journey time results is described in more detail in the individual scenario analysis in the following sections of this chapter.

4.5 DO MINIMUM SCENARIO - TRAFFIC IMPACTS

4.5.1 This sub-section demonstrates the modelled traffic impact associated with the inclusion of the four preferred proposed development sites, without any of the proposed infrastructure improvements in place.

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4.5.2 The volume to capacity ratio (V/C) has been examined as an indicator of congestion, whereby a V/C value greater than 100% is considered to signify that an approach to a junction is likely to experience queuing and delay.

JUNCTION PERFORMANCE RESULTS

4.5.3 Table 4-3 lists the junctions which have been forecast to have V/C values greater than 100% on at least one approach arm in either the AM or PM peak hour (or both). The location of these junctions is shown in Figure 4-5. Each junction has been allocated a site ID for ease of reference.

Table 4-3: Junctions which are overcapacity in the Do Minimum Scenario SITE ID JUNCTION NG Northgate - The Clink MS Mount Street - Development site access HW Quantock Road - Homberg Way WR Quantock Road - Wembdon Road WN Wembdon Road - Northfield TB Taunton Road - Broadway CR The Cross Rifles - Bristol Road/Bath Road/The Clink WB Wylds Road - Bristol Road KB King's Drive - Bristol Road WC Western Way - Chilton Street EP Express Park access - Bristol Road TM Taunton Road - Marsh Lane PH Puriton Hill - Bath Road J24 Junction 24 circulatory and site access Express Park - Bristol Road - Development Site ED access KD King's Drive - Bath Road WH Wembdon Rise - Homberg Way S1.2 Site 1 second access BS Barclay Street Site Access AC Along The Clink Along North Street going into Wembdon Road - AN Alexandra Road TH Taunton Road to Huntsworth - SB J23 Junction 23 Northbound On slip

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Figure 4-5: Junctions to be overcapacity in the Do Minimum Scenario

4.5.4 As shown in above in Figure 4-5, the town centre of Bridgwater is affected by increased congestion as a result of including the four preferred development sites as well as the committed and proposed developments.

4.5.5 The proposed A39 roundabout (Site 1, second access), Whitegate Roundabout and Homberg Way junctions have all been identified to be over capacity in the 2032 forecasts as a result of additional traffic associated with Site 1.

4.5.6 The circulatory access arm from Huntworth to M5 Junction 24 and onto the M5 northbound to be over capacity in the Do Minimum scenario as a consequence of additional traffic associated with Site 4 and Site 5.

4.5.7 Junctions along Bristol Road have been identified as being overcapacity due to future committed developments and future schemes along Bristol Road such as the Express Park.

4.5.8 Increased congestion is forecast along Taunton Road between Broadway and Showground Roundabout as a result of all proposed development.

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4.6 DO SOMETHING NORTHERN BYPASS – TRAFFIC IMPACTS

4.6.1 The Northern Bypass infrastructure option consists of a connecting single-lane carriageway link between Dunball Roundabout in the north of Bridgwater and A39 Quantock Road / Sandford Hill Roundabout. The proposed southern access to this link is via an upgraded four arm roundabout at A39 Quantock Road / Sandford Hill. The northern access goes through Dunball Roundabout and connects to a three arm priority junction with a minor road development access. The proposed location is shown in Figure 4-8.

4.6.2 Comparisons have been made between the Do Minimum scenario and each Do Something scenarios in terms of traffic flows (in pcu) and V/C.

DO SOMETHING VS DO MINIMUM ACTUAL FLOW DIFFERENCE

4.6.3 When comparing the Do Minimum scenario with the Do Something - Northern Bypass option scenario actual flows, the model indicates that the bypass would ease traffic from the town centre by nearly 170 pcu fewer in the AM and around 200 pcu fewer in the PM (along Homberg Way and the Weston Way in both directions), as shown below in Figure 4-6 and Figure 4-7.

Figure 4-6: Actual Flow difference between DS - Northern Bypass Option and DM - AM

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Figure 4-7: Actual Flow difference between DS - Northern Bypass Option and DM - PM

4.6.4 The Do Something Northern Bypass model shows that this new link could attract a flow of almost 470 pcu in the AM and 360 pcu in the PM going Northbound and nearly 270 and 420 pcu going Southbound in both time periods, respectively.

SELECT LINK ANALYSIS RESULTS

4.6.5 A select link analysis was performed on the Northern Bypass in the northbound direction. It was shown that the main users that travel along this link going travel from the Cannington area and Site number 1 towards Puriton Village and M5 Junction 24. Users travelling Southbound on the bypass make the opposite movement, travelling predominantly from M5 Junction 24 and Puriton Village to either Cannington or Site 1. The bypass is predominantly used by through traffic. This is documented in more detail in Appendix B.

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JUNCTION PERFORMANCE RESULTS

4.6.6 The modelling results for the Do Something scenario for the Northern Bypass option indicate overcapacity issues (in comparison with the Do Minimum scenario) at the following junctions.

Table 4-4: Overcapacity junctions in the Do Something Northern Bypass Option Scenario SITE ID JUNCTION NG Northgate - The Clink MS Mount Street - Development site access HW Quantock Road - Homberg Way WN Wembdon Road - Northfield BP Broadway - Salmon Parade CR The Cross Rifles - Bristol Road/Bath Road/The Clink KB King's Drive - Bristol Road WR Quantock Road - Wembdon Road TM Taunton Road - Marsh Lane PH Puriton Hill - Bath Road J24 Junction 24 circulatory access and NB onslip ED Express Park - Bristol Road - Development Site access KD King's Drive - Bath Road BS Barclay Street Site Access TB Taunton Road - Broadway EP Express Park access - Bristol Road J23 Junction 23 Northbound On slip

4.6.7 The location of these junctions is shown in Figure 4-8.

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Figure 4-8: Location Plan for Northern Bypass Option

4.6.8 When comparing the junctions that were overcapacity in the Do Minimum scenario with the Do Something Model that includes the Northern Bypass, it is clear that the northern part of the town centre would have less congestion as people reroute from Western Way onto the new bypass. The model demonstrated a positive impact on the junctions along Homberg Way and Western Way, bringing these junctions within capacity. The Site 1 second access would also be within capacity as a result of implementing the bypass.

4.6.9 The Broadway/Salmon Parade junction remains overcapacity with the new bypass in place.

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JOURNEY TIME ANALYSIS RESULTS

4.6.10 The fastest alternative route to the Northern Bypass route was compared in terms of journey times. The results for this are presented below.

Table 4-5: Journey Time Results for Northern Bypass Do Something Scenario and alternative route TIME TIME DISTANCE SPEED ID PERIOD DIRECTION ROUTE (MM:SS) (M) (KPH) A39 Quantock Road/ Sandford Hill to Dunball Roundabout JR5 13:40 8,537 37.5 (through town) NB A39 Quantock Road/ Sandford Hill to Dunball Roundabout JR6 06:40 5,640 50.8 (through Northern Bypass) AM Dunball Roundabout to A39 Quantock Road/ Sandford Hill JR5 12:26 8,570 41.4 (through town) SB Dunball Roundabout to A39 Quantock Road/ Sandford Hill JR6 04:33 5,570 73.5 (through Northern Bypass) A39 Quantock Road/ Sandford Hill to Dunball Roundabout JR5 12:37 8,537 40.6 (through town) NB A39 Quantock Road/ Sandford Hill to Dunball Roundabout JR6 05:47 5,640 58.5 (through Northern Bypass) PM Dunball Roundabout to A39 Quantock Road/ Sandford Hill JR5 14:58 8,570 34.4 (through town) SB Dunball Roundabout to A39 Quantock Road/ Sandford Hill JR6 06:10 5,570 54.2 (through Northern Bypass)

4.6.11 Table 4-5 shows that the Northern Bypass is almost 7 minutes quicker in the AM than the alternative route in both directions. In the PM the bypass is 7 minutes quicker when travelling northbound and 9 minutes quicker when travelling in the opposite direction. The speed on the alternative route is between 13 and 32 kph slower and the distance is longer so there are savings in time and costs for the bypass users.

4.7 DO SOMETHING EASTERN DISTRIBUTOR ROAD – TRAFFIC IMPACTS

4.7.1 The Eastern Distributor Road infrastructure option is divided between two sections, both assumed as 30 mph single carriageway. The first section consists of a set of improvements to the existing Bower Lane, to the east of Bridgwater. The second section links Westonzoyland Road to Colley Lane Southern Access Road, via Dunwear Lane.

4.7.2 The Bower Lane section would have increased speed and capacity. The proposed second section would include upgrading the Marsh Lane/Showground Road and Bower Lane / Dunwear junctions to four arms roundabouts. The proposed location for this infrastructure option is shown in Figure 3-1.

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DO SOMETHING VS DO MINIMUM ACTUAL FLOW DIFFERENCE

4.7.3 A comparison between the actual flows of the Do Minimum scenario and Do Something – Eastern Distributor Road scenario shows that traffic in the eastern part of the town centre would be reduced as people would be rerouting onto the new available infrastructure, especially along Broadway, between St John Street and Taunton Road junctions. This is shown below in Figure 4-9 and Figure 4-10, and applies to both peaks.

4.7.4 Traffic along the M5 between Junction 23 and Junction 24 is also shown to reduce in the AM (nearly 100 fewer pcu) and PM (nearly 250 fewer pcu northbound and about 100 fewer southbound).

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Figure 4-9: Actual Flow difference between DS - Eastern Distributor Road Option and DM - AM

Figure 4-10: Actual Flow difference between DS - Eastern Distributor Road Option and DM - PM

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4.7.5 These modelling results show that the improvements along Bower Lane would increase traffic along this route and the second section of the distributor road would have around 370 pcu travelling northbound in the AM and around 620 pcu in the PM. The southbound modelled actual flows are approximately 660 pcu in the AM and 470 pcu in the PM.

SELECT LINK ANALYSIS RESULTS

4.7.6 The select link analysis performed on the southern section of the Eastern Distributor Road option demonstrates that the main origins for people going northbound and using this route are from Taunton and the M5 northbound via Junction 23. The main destinations in both time periods are Bridgwater town centre, Bower Lane or Westonzoyland Village. The majority of vehicles travelling southbound on the Eastern Distributor Road are from Westonzoyland Village, Puriton Hill and Bower Lane travelling towards the town centre, M5 Junction 23 southbound and Taunton. This infrastructure option is used for both through and local traffic. More details about this can be found in Appendix C.

JUNCTION PERFORMANCE RESULTS

4.7.7 The modelling results for the Eastern Distributor Road Forecasting Model analysis identify high V/Cs (in comparison with the Do Minimum scenario) at the junctions listed in Table 4-6 below.

Table 4-6: Overcapacity junctions in the Do Something Eastern Distributor Road Option Scenario SITE ID JUNCTION NG Northgate - The Clink BS Barclay Street Site Access MS Mount Street - Development site access HW Quantock Road - Homberg Way WR Quantock Road - Wembdon Road WN Wembdon Road - Northfield TB Taunton Road - Broadway KB King's Drive - Bristol Road WC Western Way - Chilton Street EP Express Park access - Bristol Road TM Taunton Road - Marsh Lane PH Puriton Hill - Bath Road Junction 24 circulatory access and NB on J24 slip Express Park - Bristol Road - Development ED Site access KD King's Drive - Bath Road WH Wembdon Rise - Homberg Way S1.2 Site 1 second access Along North Street going into Wembdon AN Road - Alexandra Road WB Wylds Road - Bristol Road TH Taunton Road to Huntsworth - SB

4.7.8 The location of these junctions is shown in Figure 4-11.

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Figure 4-11: Location Plan for Eastern Distributor Road Option

4.7.9 The Eastern Distributor Road option Do Something scenario shows that not many junctions benefit from reduced congestion in Bridgwater town centre, when compared to the Do Minimum scenario. The only junctions that are no longer over capacity are the Cross Rifles Junction and those along the Clink.

4.7.10 There is a small improvement in the eastern part of the town. Despite the fact that some people reroute from Broadway between St John Street and Taunton Road junctions to the new Eastern Distributor Road, there is minimal relief on the congested junctions in the town centre. These results are consistent with the Average Speed in Bridgwater results, as presented in Figure 4-3, where the Do Minimum scenario results remain almost unchanged by implementing this infrastructure.

JOURNEY TIME ANALYSIS RESULTS

4.7.11 Two alternative routes to the Eastern Distributor Road route were compared in terms of journey times because there are two distinct sections. The results for the Eastern Distributor Road sections are presented in Table 4-7 and Table 4-8.

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Table 4-7: Journey Time Results for Eastern Distributor Road Scenario and alternative route 1 TIME TIME DISTANCE SPEED ID PERIOD DIRECTION ROUTE (MM:SS) (M) (KPH) Showground Road/Marsh Lane to A39 Puriton Hill / Bath Road JR1 14:13 6,260 26.4 (through town) NB Showground Road/Marsh Lane to A39 Puriton Hill / Bath Road JR2 11:13 6,100 32.6 (through Eastern Circulatory Road) AM A39 Puriton Hill / Bath Road to Showground Road/Marsh Lane JR1 09:52 6,260 38.1 (through town) SB A39 Puriton Hill / Bath Road to Showground Road/Marsh Lane JR2 07:33 6,100 48.5 (through Eastern Circulatory Road) Showground Road/Marsh Lane to A39 Puriton Hill / Bath Road JR1 14:26 6,260 26.0 (through town) NB Showground Road/Marsh Lane to A39 Puriton Hill / Bath Road JR2 10:48 6,100 33.9 (through Eastern Circulatory Road) PM A39 Puriton Hill / Bath Road to Showground Road/Marsh Lane JR1 10:21 6,260 36.3 (through town) SB A39 Puriton Hill / Bath Road to Showground Road/Marsh Lane JR2 07:56 6,100 46.1 (through Eastern Circulatory Road)

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Table 4-8: Journey Time Results for Eastern Distributor Road Scenario and alternative route 2 TIME TIME DISTANCE SPEED ID PERIOD DIRECTION ROUTE (MM:SS) (M) (KPH) Showground Road/Marsh Lane to A372 Westonzoyland Road JR3 07:54 4,290 32.6 (through town) NB Showground Road/Marsh Lane to A372 Westonzoyland Road JR4 02:59 2,280 45.9 (through Eastern Circulatory Road) AM A372 Westonzoyland Road to Showground Road/Marsh Lane JR3 08:06 4,400 32.6 (through town) SB A372 Westonzoyland Road to Showground Road/Marsh Lane JR4 03:01 2,280 45.3 (through Eastern Circulatory Road) Showground Road/Marsh Lane to A372 Westonzoyland Road JR3 08:21 4,290 30.8 (through town) NB Showground Road/Marsh Lane to A372 Westonzoyland Road JR4 03:05 2,280 44.4 (through Eastern Circulatory Road) PM A372 Westonzoyland Road to Showground Road/Marsh Lane JR3 08:25 4,400 31.4 (through town) SB A372 Westonzoyland Road to Showground Road/Marsh Lane JR4 02:59 2,280 45.9 (through Eastern Circulatory Road)

4.7.12 Table 4-7 and Table 4-8 demonstrate that the Eastern Distributor Road provides a considerable journey time and distance saving above the existing alternative routes. In general, journey time savings are up to 5 minutes, and distance is reduced by approximately 50%. Due to reduced congestion, vehicles are able to travel approximately 15kph faster.

4.7.13 The first alternative is between 6 and 10 kph slower than the Distributor Road. The second alternative route is between 13 and 14 kph slower than the proposed infrastructure option.

4.7.14 There are benefits from the implementation of the Eastern Distributor Road, although not as large as the other infrastructure options.

4.8 DO SOMETHING SOUTHERN BYPASS – TRAFFIC IMPACTS

4.8.1 The Southern infrastructure option involves a 60mph single-lane carriageway that links Huntworth Roundabout and the Spaxton Road/Enmore Road junction, then follows Spaxton Road to the A39. The alignment has been assumed to follow parts of the existing Durleigh Road and Campion Way. The proposed southern access to this link is via a four arm roundabout at Campion Way. The northern proposed access includes the upgrade of Enmore Road / Spaxton Road junction to a four arm roundabout. The proposed location is shown in Figure 4-14.

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DO SOMETHING VS DO MINIMUM FLOW COMPARISON

4.8.2 Comparison between the Do Minimum scenario and the Do Something - Southern Bypass option actual flow shows that traffic on the southern and northern parts of the town centre would be reduced with the bypass in place, most significantly in the AM peak, as shown below in Figure 4-12.

4.8.3 In the AM peak, there are around 250 fewer pcu travelling southbound along Quantock Road / Taunton Road and almost 280 pcu fewer travelling north.

4.8.4 In the PM peak there are around 150 fewer pcu going along Taunton Road southbound and nearly 230 fewer pcu travelling north.

Figure 4-12: Actual Flow difference between DS - Southern Bypass Option and DM - AM

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Figure 4-13: Actual Flow difference between DS - Southern Bypass Option and DM - PM

4.8.5 The Southern Bypass attracts around 700 pcu travelling south and almost 400 pcu travelling north in the AM. In the PM peak these numbers reach nearly 500 and 560 pcu, respectively.

SELECT LINK ANALYSIS RESULTS

4.8.6 A select link analysis has been undertaken along the Southern Bypass option that indicates that the majority of the users that travel northbound come from Taunton and Junction 23 on the M5, both directions and go either to Site 1, Bridgwater town centre or Cannington, in both time periods. The users travelling southbound on the bypass come mostly from Cannington, Site 1 and Bridgwater town centre and head towards either Taunton or Junction 23 of the M5 in both directions. Traffic using this bypass is mainly local. Appendix D provides more details on this.

JUNCTION PERFORMANCE RESULTS

4.8.7 The modelling results for the Do Something scenario for the Southern Bypass option indicate that the following junctions listed in Table 4-9 (in comparison with the Do Minimum scenario) are overcapacity.

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Table 4-9: Overcapacity junctions in the Do Something Southern Bypass Option Scenario SITE ID JUNCTION KB King's Drive - Bath Road MS Mount Street - Development site access TB Taunton Road - Broadway BE Broadway - Eastover - St John Street The Cross Rifles - Bristol Road/Bath CR Road/The Clink KB King's Drive - Bristol Road EP Express Park access - Bristol Road PH Puriton Hill - Bath Road CW Campion Way development site access Junction 24 circulatory access and NB on J24 slip Express Park - Bristol Road - Development ED Site access BS Barclay Street Site Access WB Wylds Road - Bristol Road

4.8.8 The location of these junctions is illustrated in Figure 4-14.

Figure 4-14: Location Plan for Southern Bypass Option

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4.8.9 It is evident that the implementation of the Southern Bypass reduces the level of congestion on the south west part of the town centre. All junctions along Quantock Road and Wembdon Road as well as the Site 1 access are within capacity with this bypass in place, so there is less congestion on the southern part of the town centre. Rerouting would be expected from Quantock Road/Taunton Road and Homberg Way/Western Way to the new bypass.

4.8.10 Implementation of the Southern Bypass would have a negative impact Broadway/ Eastover/ St John Street junction and the access to some developments on Campion Way.

JOURNEY TIME ANALYSIS RESULTS

4.8.11 The journey times results for the Southern Bypass route and the alternative route to that are presented in Table 4-10.

Table 4-10: Journey Time Results for Southern Bypasss Scenario and alternative route TIME TIME DISTANCE SPEED ID PERIOD DIRECTION ROUTE (MM:SS) (M) (KPH) Huntworth Roundabout to A39 Quantock Road/ Sandford Hill JR7 11:07 6,340 34.2 (through town) NB Huntworth Roundabout to A39 Quantock Road/ Sandford Hill JR8 06:31 5,848 53.8 (through Southern Bypass) AM A39 Quantock Road/ Sandford Hill to Huntworth Roundabout JR7 10:27 6,340 36.4 (through town) SB A39 Quantock Road/ Sandford Hill to Huntworth Roundabout JR8 07:08 5,898 49.6 (through Southern Bypass) Huntworth Roundabout to A39 Quantock Road/ Sandford Hill JR7 11:13 6,340 33.9 (through town) NB Huntworth Roundabout to A39 Quantock Road/ Sandford Hill JR8 06:07 5,848 57.4 (through Southern Bypass) PM A39 Quantock Road/ Sandford Hill to Huntworth Roundabout JR7 12:22 6,340 30.8 (through town) SB A39 Quantock Road/ Sandford Hill to Huntworth Roundabout JR8 09:04 5,898 39.0 (through Southern Bypass)

4.8.12 Table 4-10 shows that the Southern Bypass is around 5 minutes quicker in both AM and PM periods when travelling northbound. For southbound traffic, the bypass is nearly 3 minutes quicker than the alternative route. Speeds along the Southern Bypass are between 9 and 24 km/ph. slower than the alternative route.

4.8.13 The Southern Bypass promotes savings for users in terms of time and cost as it is a quicker and shorter route compared to the existing alternatives.

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4.9 DO SOMETHING ALL OPTIONS COMBINED – TRAFFIC IMPACTS

4.9.1 The All Options Combined Do Something scenario includes the Northern Bypass, the Eastern Distributor Road and the Southern Bypass infrastructure options, as they were previously designated in the individual Do Something scenarios.

4.9.2 As with the previous scenarios, this option has been compared to the Do Minimum in terms of traffic flows (in pcu) and junction V/C. Additionally, a journey time assessment has been undertaken to demonstrate the benefit of each route compared to the next best alternative.

DO SOMETHING VS DO MINIMUM ACTUAL FLOW COMPARISON

4.9.3 A clear observation of this comparison is that there is significantly less demand in Bridgwater town centre, as people reroute onto the new available routes. Figure 4-15 and Figure 4-16 below show these differences for the AM and PM peak models.

Figure 4-15: Actual Flow difference between DS - All Infrastructure Option and DM - AM

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Figure 4-16: Actual Flow difference between DS - All Infrastructure Option and DM - PM

4.9.4 The combination of all infrastructure options substantially reduces congestion in the town centre and eases traffic by approximately 330 fewer pcu in the AM and 206 fewer pcu in the PM, on Homberg Way/Western Way.

4.9.5 Travelling towards the town centre, on Taunton Road, there is a modelled reduction of almost 370 pcu in the AM and a reduction of nearly 560 pcu in the PM. For people travelling southbound on Taunton Road, there would also be less congestion as there are around 490 fewer pcu in the AM and around 180 fewer pcu in the PM.

4.9.6 Bristol Road would also have less traffic through a reduction of almost 180 pcu in the AM and nearly 140 fewer pcu in the PM travelling northbound and almost 280 and 470 fewer pcu travelling southbound.

4.9.7 Figure 4-15 and Figure 4-16 also show that traffic on the M5 reduces due to the benefit of the three infrastructure options in routing traffic between north and south Bridgwater. The model shows almost 110 fewer pcu northbound on the M5, and about 160 fewer pcu southbound in the AM peak. In the PM the M5 flow is modelled as reducing by nearly 250 pcu northbound and almost 150 pcu southbound between Junction 23 and Junction 24.

SELECT LINK ANALYSIS RESULTS

4.9.8 A select link analysis was performed on each of the new infrastructure options in both AM and PM peak periods in both directions, as it was previously performed in the individual infrastructure option scenarios. More detail is shown in Appendix E.

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4.9.9 This analysis reveals that the main users of the Northern Bypass travelling northbound travel from Cannington and Site 1 toward Puriton Village, Junction 23 on the M5 Northbound and Pawlett Village in both time periods. By comparing these results with the Individual Northern Bypass Do Something scenario, there are no additional trips southbound at Junction 23 on the M5 in this scenario because the Southern Bypass also exists as an alternative for traffic.

4.9.10 For users travelling southbound on the Northern Bypass the main origins are Puriton Village, M5 Junction 23 and Pawlett Village and the main destinations are Cannington and Site 1. These results are similar to those demonstrated in the northbound direction for the individual Northern Bypass Only scenario. In the All Infrastructure scenario there are not any additional trips coming from southbound M5 because the Southern Bypass is available for these users. A large amount of through traffic uses this bypass.

4.9.11 The select link analysis on the Eastern Distributor Road northbound shows that users predominantly travel from Taunton or M5 Junction 23 from the south and head towards either the town centre or Westonzoyland Village. This is a similar profile to the users on the individual Eastern Distributor Road scenario.

4.9.12 People travelling on the Eastern Distributor Road southbound travel predominantly from Puriton and Westonzoyland village towards the town centre, Taunton and M5 Junction 24. This is a very similar behaviour for users in the individual infrastructure scenario. This route has more demand as a result of the combination of all infrastructure options and has both local and through traffic travelling on it.

4.9.13 The select link on the Southern Bypass northbound illustrates demand is mainly from the town centre, Taunton and M5 Junction 24 towards Cannington and Site 1.

4.9.14 By looking at the Southern Bypass actual flows in the select link analysis, it can be observed that the main southbound demands are from Cannington and Site 1 travelling toward the town centre, Taunton and Junction 24. Traffic on the Southern Bypass is mainly local.

JUNCTION PERFORMANCE RESULTS

4.9.15 Table 4-11 lists junctions which remain over capacity regardless of the implementation of all three infrastructure options.

Table 4-11: Overcapacity junctions in the Do Something All Infrastructure Option Combined Scenario SITE ID JUNCTION KD King's Drive - Bath Road NG Northgate - The Clink BS Barclay Street Site Access MS Mount Street - Development site access PH Puriton Hill - Bath Road HD Huntworth Development Site access Junction 24 circulatory access and NB on J24 slip Express Park - Bristol Road - ED Development Site access EP Express Park access - Bristol Road J23 Junction 23 NB on slip

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4.9.16 The location of all infrastructure option is shown in Figure 4-17.

Figure 4-17: Location Plan for All Infrastructure Option

4.9.17 There are fewer overcapacity junctions in the Do Something scenario. There are three new routes available and people reroute onto these, easing the congestion in the town centre.

4.9.18 A positive impact is seen on Homberg Way/Western Way and along Quantock Road/Broadway, as there are not any overcapacity junctions in this scenario. The introduction of Southern and Northern Bypasses ease the access for traffic at Site 1.

4.9.19 Congestion on Bristol Road and Taunton Road also improves through a reduction in demand.

4.9.20 Although in the overall town centre there is less congestion, the Huntworth Development Site access (HD) becomes over capacity due to the implementation of the Southern Bypass access.

4.9.21 The overall outcome is that the implementing all three infrastructure options would result in a positive effect by addressing the town’s congestion and improving current traffic conditions.

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JOURNEY TIME ANALYSIS RESULTS

4.9.22 Journey time analysis was performed for each infrastructure individually and comparisons were made between alternative routes within the all infrastructure options combined model.

4.9.23 The results for the Northern Bypass and the alternative route for the journey times are presented below in Table 4-12.

Table 4-12: Northern Bypass and alternative route journey time results TIME TIME DISTANCE SPEED PERIOD DIRECTION ROUTE ID (MM:SS) (M) (KPH) A39 Quantock Road/ Sandford Hill to Dunball Roundabout JR5 12:48 8,537 40.0 (through town) NB A39 Quantock Road/ Sandford Hill to Dunball Roundabout JR6 05:45 5,640 58.9 (through Northern Bypass) AM Dunball Roundabout to A39 Quantock Road/ Sandford Hill JR5 12:15 8,570 42.0 (through town) SB Dunball Roundabout to A39 Quantock Road/ Sandford Hill JR6 04:35 5,570 72.9 (through Northern Bypass) A39 Quantock Road/ Sandford Hill to Dunball Roundabout JR5 12:28 8,537 41.1 (through town) NB A39 Quantock Road/ Sandford Hill to Dunball Roundabout JR6 05:19 5,640 63.6 (through Northern Bypass) PM Dunball Roundabout to A39 Quantock Road/ Sandford Hill JR5 14:37 8,570 35.2 (through town) SB Dunball Roundabout to A39 Quantock Road/ Sandford Hill JR6 05:32 5,570 60.4 (through Northern Bypass)

4.9.24 Table 4-12 shows that the Northern Bypass route is shorter and it is nearly 7 minutes quicker northbound in both time periods. The southbound route is almost 8 minutes quicker in the AM and 9 minutes quicker in the PM, so this would translate in time savings and cost benefits for users. The speed along the Northern Bypass is between 19 and 31 kph higher than the alternative route. These results are similar to the individual Do Something infrastructure assessment.

4.9.25 The Eastern Distributor Road has two alternative routes as shown previously in Figure 4-4. This is because there are two clear sections, and so it has been assessed using two routes. The results for both routes are shown below in Table 4-13 and Table 4-14.

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Table 4-13: Eastern Distributor Road and first alternative route journey time results TIME TIME DISTANCE SPEED ID PERIOD DIRECTION ROUTE (MM:SS) (M) (KPH) Showground Road/Marsh Lane to A39 Puriton Hill / Bath Road JR1 12:22 6,260 30.4 (through town) NB Showground Road/Marsh Lane to A39 Puriton Hill / Bath Road JR2 09:42 6,100 37.7 (through Eastern Circulatory Road) AM A39 Puriton Hill / Bath Road to Showground Road/Marsh Lane JR1 09:30 6,260 39.5 (through town) SB A39 Puriton Hill / Bath Road to Showground Road/Marsh Lane JR2 07:35 6,100 48.3 (through Eastern Circulatory Road) Showground Road/Marsh Lane to A39 Puriton Hill / Bath Road JR1 13:13 6,260 28.4 (through town) NB Showground Road/Marsh Lane to A39 Puriton Hill / Bath Road JR2 10:28 6,100 35.0 (through Eastern Circulatory Road) PM A39 Puriton Hill / Bath Road to Showground Road/Marsh Lane JR1 09:44 6,260 38.6 (through town) SB A39 Puriton Hill / Bath Road to Showground Road/Marsh Lane JR2 07:53 6,100 46.4 (through Eastern Circulatory Road)

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Table 4-14: Eastern Distributor Road and second alternative route journey time results TIME TIME DISTANCE SPEED PERIOD DIRECTION ROUTE ID (MM:SS) (M) (KPH) Showground Road/Marsh Lane to A372 Westonzoyland Road JR3 07:37 4,290 33.8 (through town) NB Showground Road/Marsh Lane to A372 Westonzoyland Road JR4 03:00 2,280 45.6 (through Eastern Circulatory Road) AM A372 Westonzoyland Road to Showground Road/Marsh Lane JR3 07:57 4,400 33.2 (through town) SB A372 Westonzoyland Road to Showground Road/Marsh Lane JR4 03:02 2,280 45.1 (through Eastern Circulatory Road) Showground Road/Marsh Lane to A372 Westonzoyland Road JR3 07:38 4,290 33.7 (through town) NB Showground Road/Marsh Lane to A372 Westonzoyland Road JR4 03:07 2,280 43.9 (through Eastern Circulatory Road) PM A372 Westonzoyland Road to Showground Road/Marsh Lane JR3 08:00 4,400 33.0 (through town) SB A372 Westonzoyland Road to Showground Road/Marsh Lane JR4 02:58 2,280 46.1 (through Eastern Circulatory Road)

4.9.26 The first alternative route shows that the Eastern Distributor Road is approximately 2.5 minutes faster when travelling northbound in both time periods and approximately 2 minutes faster when travelling southbound in the AM and PM. The speed along the distributor road is around 10kph quicker. The individual infrastructure assessment when compared to alternative route 1 has an identical result.

4.9.27 The second alternative route is also around 5 minutes slower than the Eastern Distributor Road route in both AM and PM going in both directions, like the individual assessment for this infrastructure.

4.9.28 The results for the Southern Bypass and the alternative route are presented in Table 4-15.

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Table 4-15: Southern Bypass and alternative route journey time results TIME TIME DISTANCE SPEED PERIOD DIRECTION ROUTE ID (MM:SS) (M) (KPH) Huntworth Roundabout to A39 Quantock Road/ Sandford Hill JR7 10:39 6,340 35.7 (through town) NB Huntworth Roundabout to A39 Quantock Road/ Sandford Hill JR8 06:15 5,848 56.1 (through Southern Bypass) AM A39 Quantock Road/ Sandford Hill to Huntworth Roundabout JR7 10:21 6,340 36.8 (through town) SB A39 Quantock Road/ Sandford Hill to Huntworth Roundabout JR8 07:00 5,898 50.6 (through Southern Bypass) Huntworth Roundabout to A39 Quantock Road/ Sandford Hill JR7 11:23 6,340 33.4 (through town) NB Huntworth Roundabout to A39 Quantock Road/ Sandford Hill JR8 06:05 5,848 57.7 (through Southern Bypass) PM A39 Quantock Road/ Sandford Hill to Huntworth Roundabout JR7 11:23 6,340 33.4 (through town) SB A39 Quantock Road/ Sandford Hill to Huntworth Roundabout JR8 07:02 5,898 50.3 (through Southern Bypass)

4.9.29 Table 4-15 shows that the Southern Bypass route is shorter than the alternative route and faster as well. In the AM, travelling northbound is approximately 4 minutes quicker than using the alternative route and going southbound is almost 3.5 minutes faster. As for the PM, travelling northbound is around 5 minutes faster on the bypass and going southbound is almost 4.5 minutes faster as well. In general terms, the speed is between 14 and 24 kph faster on the bypass route. These results are very similar to the individual infrastructure assessment in terms of journey times.

Bridgwater Transport Options - Infrastructure Options Technical Report WSP | Parsons Brinckerhoff Somerset County Council Project No 62102386 41

5 CONCLUSION 5.1 SUMMARY OF PROCESS

5.1.1 A single demand scenario was agreed with SDC based upon the forecasting work discussed in the ‘Bridgwater Transport options – Forecasting Report’. This study has sought to identify the potential traffic benefit of constructing additional infrastructure around Bridgwater. Four potential infrastructure scenarios have been considered, comprising of combinations of three proposed infrastructure schemes. These were defined as follows:

A. Northern Bypass only

B. Eastern Distributor Road only

C. Southern Distributor Road only

D. Implementation of all three infrastructure options.

5.1.2 These scenarios have been tested in terms of their benefit to traffic flows, journey times and volume to capacity ratio, and network wide statistics.

5.2 SUMMARY OF FINDINGS

5.2.1 The implementation of all three infrastructure options in combination provided the greatest improvement to traffic by all measures considered within this report. Therefore, this summary of findings only discusses a comparison of benefits between each of the individual infrastructure scenarios.

5.2.2 The Northern Bypass and the Southern Bypass scenarios have very similar network wide improvements compared to the Do Minimum scenario. Note that the Southern Bypass scenario generally benefits local traffic whilst the Northern Bypass and Eastern Distributor Road scenarios mainly benefit longer distance through traffic.

5.2.3 The Southern Bypass scenario had greatest impact in terms of reducing traffic congestion in the town centre and all junctions along Quantock Road, Wembdon Road and the access to proposed Site 1. The Southern Bypass attracted trips that would otherwise have used the Quantock Road/Taunton Road and Homberg Way/Western Way junctions.

5.2.4 In terms of journey time savings, the Northern Bypass provides the greatest journey benefit.

5.2.5 The impact of each infrastructure option is summarised by each measure in Table 5-1.

Bridgwater Transport Options - Infrastructure Options Technical Report WSP | Parsons Brinckerhoff Somerset County Council Project No 62102386 42

Table 5-1: Main infrastructure results - individual assessment TRAFFIC BENEFIT NORTHERN EASTERN SOUTHERN ASSESSMENT BYPASS DISTRIBUTOR BYPASS ROAD Demand attraction a aa aaa Average speed in aaa a aa Bridgwater area Model wide journey time aa a aaa savings Route specific journey aaa a aa time savings Junction performance aa a aaa impact Overall Assessment aa a aaa

KEY: a LOWEST IMPACT aa MODERATE IMPACT aaaGREATEST IMPACT

5.2.6 Overall, this assessment has revealed that the Southern Bypass provides most significant traffic benefit, having the greatest impact for all measures, except the average speed and journey time savings.

5.2.7 The Eastern Distributor Road scenario has the least traffic benefit when assessed against all measures considered in this report, with the exception of the demand attracted.

5.3 LIMITATIONS

5.3.1 This is a high level assessment, making broad assumptions in relation to the nature of the developments and access arrangements. It does not replace the requirement for a detailed and robust Transport Assessment supporting any future planning applications, and nor does it guarantee that any proposals would be acceptable to the Highway Authority.

5.3.2 It is important to emphasise that this assessment focuses only on traffic impact and that a full appraisal would cover environmental and social impacts. This assessment only considered the benefits without considering the relative costs of the proposals.

5.3.3 The assessment also includes various assumptions with regard to background growth and specific development. For example, at Hinkley Point C and Huntspill Energy Park. Should changes in timing or development type occur in the future, this could have a large impact on the results.

5.3.4 The TSTM3 model has been adapted, but has not undergone a detailed review or re- calibration for the purpose of this assessment. Results from this model should be considered only as an indication of scheme benefits rather than a robust forecast.

Bridgwater Transport Options - Infrastructure Options Technical Report WSP | Parsons Brinckerhoff Somerset County Council Project No 62102386 43

5.4 FURTHER WORK

5.4.1 Should it be required to consider one or more of these proposals further, the next step would in all likelihood be an ‘Options Assessment Report’ (OAR) (as defined in the WebTAG ‘Transport Appraisal Process’, January 2014).

5.4.2 Although these three infrastructure schemes were tested in this assessment, other options (such as travel planning for new and/or existing areas to encourage modal shift) could be considered. This exercise would need to be taken forward into an OAR.

5.4.3 Beyond an OAR, a more detailed appraisal considering all aspects of social, environmental, economic and transport impacts would be required. If public sector funding were to be required it is very likely that a full WebTAG-compliant appraisal would need to support a business case; this would also require a full refresh of the SATURN traffic model.

5.4.4 Regardless of funding source, any future site(s) would need to be supported by a Transport Assessment identifying local infrastructure improvements (including site access arrangements) where required, and an Environmental Impact Assessment. The detailed requirements for any planning application would need to be discussed with the Local Planning Authority and the Highway Authorities (both SCC and, it is to be expected, Highways England).

Bridgwater Transport Options - Infrastructure Options Technical Report WSP | Parsons Brinckerhoff Somerset County Council Project No 62102386 Appendix A

CONVERGENCE RESULTS

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT A1 – DO MINIMUM SCENARIO

CONVERGENCE WEBTAG AM PM PARAMETER CRITERIA Number of Assignment/Simulation - 47 34 Loops Convergence Gap (%) 0.021 0.022 0.006 0.027 previous 3 loops 0.007 0.019 Less than 0.007 0.021 Assignment Delta (%) 0.1%* 0.017 0.014 0.007 0.015 previous 3 loops 0.008 0.012 0.007 0.015

Percentage of links with Four 99.3 97.5 flows change (P) <1% consecutive iterations 99.4 98.7 greater previous 3 loops than 98% 99.2 97.7 99.3 97.7 Percentage of links with cost (delay) change (P2) Four 99.6 99.0 <1% consecutive iterations 99.7 99.0 greater previous 3 loops than 98% 99.5 98.8 99.7 99.0

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT A2 – DO SOMETHING NORTHERN BYPASS SCENARIO

CONVERGENCE WEBTAG AM PM PARAMETER CRITERIA Number of Assignment/Simulation - 34 42 Loops Convergence Gap (%) 0.025 0.026 0.019 0.017 previous 3 loops 0.024 0.019 Less than 0.030 0.022 Assignment Delta (%) 0.1%* 0.008 0.007 0.008 0.009 previous 3 loops 0.009 0.009 0.010 0.007

Percentage of links with Four 98.9 99.0 flows change (P) <1% consecutive iterations 99.0 97.6 greater previous 3 loops than 98% 98.7 97.5 98.8 99.0 Percentage of links with cost (delay) change (P2) Four 99.4 99.0 <1% consecutive iterations 99.3 98.7 greater previous 3 loops than 98% 99.2 98.8 99.0 99.0

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT A3 – DO SOMETHING EASTERN DISTRIBUTOR ROAD SCENARIO

WEBTAG CONVERGENCE PARAMETER AM PM CRITERIA Number of Assignment/Simulation - 31 36 Loops Convergence Gap (%) 0.026 0.019 0.018 0.027 previous 3 loops 0.011 0.021 Less than 0.014 0.019 Assignment Delta (%) 0.1%* 0.009 0.008 0.008 0.011 previous 3 loops 0.012 0.009 0.010 0.010

Percentage of links with Four 98.6 98.7 flows change (P) <1% consecutive iterations 98.6 97.6 greater previous 3 loops than 98% 98.9 99.0 98.2 97.5 Percentage of links with cost (delay) change (P2) Four 99.3 99.0 <1% consecutive iterations 99.1 98.9 greater previous 3 loops than 98% 99.3 99.3 98.9 99.0

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT A4 – DO SOMETHING SOUTHERN BYPASS SCENARIO

WEBTAG CONVERGENCE PARAMETER AM PM Criteria Number of Assignment/Simulation - 30 49 Loops Convergence Gap (%) 0.008 0.022 0.012 0.013 previous 3 loops 0.016 0.019 Less than 0.014 0.017 Assignment Delta (%) 0.1%* 0.010 0.007 0.012 0.008 previous 3 loops 0.010 0.009 0.009 0.008

Percentage of links with Four 98.3 99.1 flows change (P) <1% consecutive iterations 98.1 98.1 greater previous 3 loops than 98% 98.4 99.0 98.3 98.6 Percentage of links with cost (delay) change (P2) Four 99.4 99.3 <1% consecutive iterations 99.1 98.9 greater previous 3 loops than 98% 99.2 99.0 99.1 99.1

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT A5 – DO SOMETHING ALL INFRASTRUCTURE OPTIONS SCENARIO

WEBTAG CONVERGENCE PARAMETER AM PM Criteria Number of Assignment/Simulation - 29 36 Loops Convergence Gap (%) 0.009 0.014 0.011 0.023 previous 3 loops 0.009 0.018 Less than 0.011 0.017 Assignment Delta (%) 0.1%* 0.009 0.008 0.008 0.007 previous 3 loops 0.008 0.007 0.013 0.009

Percentage of links with Four 98.9 99.1 flows change (P) <1% consecutive iterations 98.9 98.1 greater previous 3 loops than 98% 98.9 99.4 98.4 97.6 Percentage of links with cost (delay) change (P2) Four 99.4 99.1 <1% consecutive iterations 99.6 98.7 greater previous 3 loops than 98% 99.5 99.4 99.4 99.2

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT Appendix B

DO SOMETHING SCENARIO - NORTHERN BYPASS OPTION SELECT LINK ANALYSIS

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT B1 – DO SOMETHING SCENARIO – NORTHERN BYPASS OPTION – AM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT B2 – DO SOMETHING SCENARIO – NORTHERN BYPASS OPTION – PM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT B3 – DO SOMETHING SCENARIO – NORTHERN BYPASS OPTION – AM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT B4 – DO SOMETHING SCENARIO – NORTHERN BYPASS OPTION – PM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT Appendix C

DO SOMETHING SCENARIO - EASTERN DISTRIBUTOR ROAD OPTION SELECT LINK ANALYSIS

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT C1 – DO SOMETHING SCENARIO – EASTERN DISTRIBUTOR ROAD OPTION – AM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT C2 – DO SOMETHING SCENARIO – EASTERN DISTRIBUTOR ROAD OPTION – PM – NORTH BOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT C3 – DO SOMETHING SCENARIO – EASTERN DISTRIBUTOR ROAD OPTION – AM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT C4 – DO SOMETHING SCENARIO – EASTERN DISTRIBUTOR ROAD OPTION – PM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT Appendix D

DO SOMETHING SCENARIO – SOUTHERN BYPASS OPTION SELECT LINK ANALYSIS

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT D1 – DO SOMETHING SCENARIO – SOUTHERN BYPASS OPTION – AM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT D2 – DO SOMETHING SCENARIO – SOUTHERN BYPASS OPTION – PM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT D3 – DO SOMETHING SCENARIO – SOUTHERN BYPASS OPTION – AM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT D4 – DO SOMETHING SCENARIO – SOUTHERN BYPASS OPTION – PM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT Appendix E

DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION SELECT LINK ANALYSIS

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E1 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE NORTHERN BYPASS – AM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E2 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE NORTHERN BYPASS – PM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E3 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE NORTHERN BYPASS – AM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E4 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE NORTHERN BYPASS – PM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E5 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE EASTERN DISTRIBUTOR ROAD – AM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E6 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE EASTERN DISTRIBUTOR ROAD – PM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E7 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE EASTERN DISTRIBUTOR ROAD – AM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E8 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE EASTERN DISTRIBUTOR ROAD – PM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E9 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE SOUTHERN BYPASS – AM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E10 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE SOUTHERN BYPASS – PM – NORTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E11 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE SOUTHERN BYPASS – AM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT E12 - DO SOMETHING SCENARIO – ALL INFRASTRUCTURE OPTION – SELECT LINK ON THE SOUTHERN BYPASS – PM – SOUTHBOUND

Bridgwater Transport Options - Forecast Report WSP | Parsons Brinckerhoff Somerset County Council Project No 287584CQ-PTT