St Austell Transport Strategy Development
Appendix A – Highways Strategy Report
May 2017
St. Austell Area Transport Modelling: Highways Strategy Report
Cornwall Council
September 2011
St. Austell Area Transport Modelling: Highways Strategy Report
WHV285300DL/5/3
Prepared for Cornwall Council Carrick House Truro Cornwall TR1 1EB
Prepared by Parsons Brinckerhoff The Forum Barnfield Road Exeter EX1 1QR
01392 229700 www.pbworld.co.uk
Report Title : Highways Strategy Report
Report Status : Final Version
Job No : WHV285300DL
Date : September 2011
Prepared by :
Checked by :
Approved by :
Document History and Status Report Date of Prepared By: Checked By: Approved By: Issue Issue
1 28/04/11
2 15/06/11
3 21/09/11
AUTHORISATION SHEET
Client: Cornwall Council Project: St. Austell Transport Modelling
PREPARED BY Name: Position: Regional Associate, Transportation Planning / Transportation Planner Date: September 2011 AGREED BY Name: Position: Regional Associate, Transportation Planning / Transportation Planner Date: September 2011 AUTHORISED FOR ISSUE Name: Position: Regional Associate, Transportation Planning Date: September 2011 DISTRIBUTION ACCEPTED BY Name: Position: Transportation, Cornwall Council Date: September 2011
CONTENTS Page
1 INTRODUCTION 1 1.1 Background 1 1.2 St. Austell, St. Blazey and China Clay Area Regeneration Plan 1 1.3 St. Austell and China Clay Area Eco-Communities 1 1.4 Connecting Cornwall: 2030 2 1.5 St. Austell Area Transport Model 2 1.6 Previous Reports 2 1.7 Purpose of Report 2 1.8 Key Locations 4 1.9 Strategic Road Network 5
2 SUMMARY OF EXISTING CONDITIONS 6 2.1 Introduction 6 2.2 Traffic Flow Analysis 6 2.3 Seasonality 10 2.4 Summary 12
3 FUTURE DEVELOPMENT 13 3.1 Introduction 13 3.2 Eco Communities 13 3.3 Development Phasing 15 3.4 Sustainability 15
4 ECO-COMMUNITY TRANSPORT SCHEMES 16 4.1 Introduction 16 4.2 Eco-Community Transport Schemes 16 4.3 Park and Ride 16 4.4 Highways Schemes 16
5 ST. AUSTELL AREA TRANSPORT MODEL 17 5.1 Introduction 17 5.2 Base Year Model 17 5.3 Forecasting 18 5.4 Scheme Assessments 19 5.5 Summary of Modelling Methodology 19
6 INFRASTRUCTURE PHASING 20 6.1 Introduction 20 6.2 Standard Trip Rate Assessment 20 6.3 Summary of Strategy 28 6.4 Sustainable Trip Generation Assessment 28
September 2011
7 HIGHWAYS IMPROVEMENT SCHEMES 31 7.1 Introduction 31 7.2 Scredda Roundabout 31 7.3 Carclaze Roundabout 32 7.4 Slades Road / Polkyth Road Junction 32 7.5 Mount Charles Roundabout 32
8 SUMMARY 34 8.1 Introduction 34 8.2 Existing Conditions 34 8.3 Future Conditions 34 8.4 Development and Infrastructure Phasing Strategy 34
September 2011 ST. AUSTELL AREA HIGHWAYS STRATEGY TRANSPORT MODELLING REPORT
1 INTRODUCTION
1.1 Background
1.1.1 The St. Austell, St. Blazey and China Clay areas are diverse. St. Austell itself is a large town and is the second largest urban area in Cornwall in terms of population. The area has been affected by the restructuring of the China Clay industry which has been employing fewer people for many decades. This decline has had an impact on companies involved in the wider supply chains and associated services. In addition, over the last 20 years the area has faced significant changes, including large-scale house-building and the emergence of the Eden Project, which have had an impact on traffic and the local highways network. There is now an emphasis on regeneration of the area.
1.1.2 The town currently suffers from congestion at peak times, particularly along the A390 to the south of the town. This road is a major through-route, linking Truro to St. Austell and towns in the south-east of Cornwall; therefore congestion during commuting hours is common. This congestion is exacerbated in the extended summer period by the location of popular tourist attractions such as the Eden Project, where the majority of visitors arrive by private car. Rat-running has therefore become prevalent in the town to avoid delays on this corridor. Congestion is also experienced on the A391, which links St. Austell to the A30, particularly in the area to the north of Scredda.
1.2 St. Austell, St. Blazey and China Clay Area Regeneration Plan
1.2.1 The St. Austell, St. Blazey and China Clay Area Regeneration Plan has been produced to predominantly provide support for transformational development projects. This has particularly arisen as there is significant development pressure in the area and the Council knows it will receive substantial planning applications in 2011. The area is a Cornwall Council identified regeneration priority; there is a need for further regeneration which can build upon the work which has been undertaken in recent years in the China Clay area. The aim is to promote a new economic base rather than manage decline, leading to economic, environmental and community benefits. The Plan will inform and be informed by the development of the Core Strategy.
1.2.2 To inform the Regeneration Plan, a number of transport strategies have been produced to demonstrate how the developments within the Regeneration Plan area will be supported and delivered. This document details the Highway Strategy, and should be considered alongside the Bus Strategic Plan and the Walking and Cycling Strategies1.
1.3 St. Austell and China Clay Area Eco-Communities
1.3.1 In 2008, the Government launched plans to build a number of ‘eco-towns’ across the UK, to build communities to live and work with considerations to environmental and social values. Imerys submitted a proposal for an eco-town, and the St Austell (China Clay Community) is one of only four locations in the country supported by the Planning Policy Statement: Eco-towns. This supplementary document to Planning Policy Statement (PPS) 1 sets out the broad requirements for any proposals that come forward as an ‘eco-town’ and the principles to be considered sustainable. Imerys have now joined forces with the developer Orascom and formed the joint venture company Eco-Bos to take forward their proposals.
1 These documents and the Regeneration Plan can be found on the Cornwall Council website at http://www.cornwall.gov.uk/default.aspx?page=27043.
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1.4 Connecting Cornwall: 2030
1.4.1 Cornwall’s third Local Transport Plan, Connecting Cornwall: 2030 was published in April 2011. The document is supported by an Implementation Plan, which covers the period from 2011 – 2015.
1.4.2 The Connecting Cornwall document sets the transportation strategy over the next 20 years, and considers improvements to the transport network and services and how these may be delivered. The strategy aligns with the Sustainable Community Strategy and Local Development Framework, to produce an integrated strategy for sustainable travel across the county, as well as planning for future sustainable development. This overarching strategy will guide planning of future development within St. Austell to ensure the sustainability of developments is maximised.
1.5 St. Austell Area Transport Model
1.5.1 A transport model of the St. Austell, St. Blazey and China Clay areas has been developed by Parsons Brinckerhoff on behalf of Cornwall Council, in order to assess the impact of future development and to identify required improvement schemes and measures to mitigate this impact. The model has been used to assess the impact of the potential development on the local and strategic highway networks, St. Austell town centre and key junctions within the local area. The transport model is described in more detail in Section 5.
1.6 Previous Reports
1.6.1 A number of previous reports have been produced as part of this project. These are:
x Baseline Conditions Report (Report No. WHV285300/1/3)
x Traffic Survey Report (Report No. WHV285300/2/1)
x Local Model Validation Report (Report No. WHV285300/3/1)
x Forecasting Report (Report No. WHV285300/4/1)
1.7 Purpose of Report
1.7.1 This report summarises the existing conditions on the transport network in the St. Austell area, details the outputs from the assessments of the impact of future development and identifies possible phasing of improvement schemes.
1.7.2 The report is prompted by proposals for the eco-communities which have tacit long term development scenarios. Other development proposals within the area are considered as possible scenarios, giving some definition to the locations at which future traffic loadings are likely to be added to the network. None of these modelled scenarios imply any predisposition from Cornwall Council to allow these developments to come forward.
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1.7.3 The report is set out as follows:
x Section 2: Summary of Existing Conditions; this section outlines existing traffic flows in St. Austell throughout the year and identifies areas of congestion.
x Section 3: Future Development; this section details the development included in the transport modelling scenarios;
x Section 4: Transport Schemes; this section summarises the transport schemes included within the modelling scenarios;
x Section 5: St. Austell Transport Model; this section summarises the methodology used in the transport modelling assessments;
x Section 6: Infrastructure Phasing; this section details outputs from the modelling assessments of each of the future year scenarios;
x Section 7: Highways Improvements; this section identifies the junction improvements schemes required to provide mitigation at junctions where congestion is predicted to occur in future years.
x Section 8: Summary; this section provides a summary of the report and the identified transport strategy.
x Appendix 1; this provides a list of measures included within the eco- communities travel plan, aimed to promote and maximise sustainable travel.
x Appendix 2; this provides detailed outputs from the transport model showing the areas of congestion for each of the modelled future years to 2030.
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1.8 Key Locations
1.8.1 This report refers to a number of key links and junctions within the St. Austell area. A plan showing the key locations is shown in Figure 1 below.
St. Austell Key Junctions
Bugle Signalised Junction
B3274 B3374
Singlerose Rbt
A391
Carluddon Double Mini Rbts Carclaze Rbt
Scredda Rbt Menear Rbt
B3274 Trenowah Rbt Treverbyn Rd / Slades Rd Signalised Junction Britannia Rbt
Slades Rd / Polkyth Rd A390 Signalised Junction
A3058
A390 A391 / A390 A390 / A3058 Signalised Junction Triangle Mount Charles Rbt
Asda Rbt
A390 A390 Double Mini Rbts Sawles Signalised Junction
Licence Key: JCPMUZR2QCHE23K
Figure 1: Key Link and Junction Locations in the St. Austell Area
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1.9 Strategic Road Network
1.9.1 The Highways Agency has some concerns about the impact of future development in the St. Austell area on the future operation of a number of junctions on the A30 and A38. These junctions are listed below, and are shown in Figure 2:
x A30 Innis Downs junction;
x A30 Victoria Interchange;
x A30 Highgate Hill junction;
x A30 Blue Anchor junction;
x A30 Summercourt junction;
x A38 Dobwalls Roundabout.
Figure 2 – A30 / A38 Junction Locations
1.9.2 The A30 / A391 Innis Downs junction and A30 / B3274 Victoria Interchange junction were both improved as part of the A30 Bodmin to Indian Queens improvement; the A38 / A390 Dobwalls roundabout was also recently improved as part of the A38 Dobwalls Bypass improvement. As such, these junctions currently operate well within capacity.
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2 SUMMARY OF EXISTING CONDITIONS
2.1 Introduction
2.1.1 Congestion and delays are experienced on a number of routes in the St. Austell area on a regular basis. Congestion is particularly severe on the A390 to the south of the town, which serves as a through route from the east and north to Truro, as well as providing access to a number of locations within St. Austell town centre. As a result of this congestion, drivers use a number of rat-runs to avoid delays, which adds to traffic already using these roads as a logical route. In the summer, traffic flows are often increased, particularly due to the attraction of the Eden Project, located to the north- east of the town centre. Congestion is also experienced on the A391, which links St. Austell to the A30, particularly in the area to the north of Scredda. A neutral month has been modelled so seasonal increases in demand and congestion are not reflected in the results detailed later in this report.
2.1.2 The existing conditions within the St. Austell area are described in detail in the Baseline Conditions Report. The AM peak (08:00-09:00) and the PM peak (17:00-18:00) have been modelled. Some of the key information from this report is summarised in the following sections.
2.2 Traffic Flow Analysis
2.2.1 Figure 3 shows traffic count data for the AM peak in September 2010. The roads are coloured in terms of the 2 way traffic flow on the link. The diagram shows that in the AM Peak, high traffic volumes are experienced on the A390 to the south of St. Austell (where flows exceed 1,000 veh/hr/direction in some places) and A391 north of Scredda. A number of roads in the area have relatively high traffic flows, which suggests that rat- running may be occurring. This relieves some of the stresses on the major roads and junctions in the network.
2.2.2 Figure 4 shows traffic counts for the PM peak in September 2010. The roads are coloured in terms of the 2 way traffic flow on the link. The figure shows that flows are very high on the A390 to the south of the town, with flows exceeding 1,250 veh/hr/direction in some places. This volume of traffic demonstrates the congestion problems experienced on this route. Compared to the AM peak, almost all roads experience higher traffic flows.
2.2.3 The traffic flow diagrams provide an indication of areas of congestion within and around St. Austell. Although the capacity of specific links and junctions is dependent on their individual characteristics, traffic flows which exceed 1,000 veh/hr/direction on links within and nearby an urban area such as St. Austell would generally result in congestion or slowing moving traffic conditions. The flows presented in Figures 3 and 4 therefore show that congested conditions are experienced along the A390 through St. Austell in both peak periods. In addition, some congestion is also experienced on the A391 north of Scredda.
2.2.4 Figure 5 shows the 12-hour flow in September 2010. The roads are coloured in terms of the 2 way traffic flow on the link. From the figure, it is clear that the highest flows are experienced on the A390. The A391 experiences lower flows; however, the B3274 also experiences a 12-hour flow of between 10,000 and 15,000 vehicles a day in both directions, which would suggest that alternative routes are used to access St. Austell from the north.
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Figure 3 – AM Peak Hour (08:00 – 09:00) 2 Way Traffic Flows in St. Austell (September 2010) - From Count Data * blue = no data available
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Figure 4 – PM Peak Hour (17:00 – 18:00) 2-way Traffic Flows in St. Austell (September 2010) – From Count Data * blue = no data available
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Figure 5 – 12-Hour (07:00 – 19:00) 2-way Traffic Flows in St. Austell (September 2010) from count data * blue = no data available
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2.2.5 Table 1 shows a summary of flows experienced at selected sites taken from within the figures shown above.
AM Peak PM Peak 12-Hour
(2 Way) (2 Way) (2 way)
A391: Carluddon 1,379 1,367 13,670
A390 East: East of the A390 / 1,890 1,950 19,500 A391 junction
A390 West: Coliza Hill 1,190 1,411 14,110
A390: Southbourne Road 1,922 2,155 21,570
A391: Carn Grey 863 1,046 10,460
Table 1 – Traffic flows for September 2010 for selected sites (veh/hr)
2.2.6 Generally, all flows are higher in the PM peak, rather than the AM peak. The highest flows are experienced on the A390 at Southbourne Road, with over 21,000 vehicles observed (2-way) in a 12-hour period. The table shows that the volume of traffic on the A390 through the town is high; given the many junctions on this section this leads to frequent congestion and delays on this route.
2.2.7 Traffic flows are also high to the east of the town, showing the high volume of traffic that travels through the town on the A390.
2.3 Seasonality
2.3.1 Traffic flows in St. Austell are significantly higher in summer than in neutral month periods, due to the increase in tourist traffic at these times. Figure 6 shows a monthly flow profile (using 2-way flows) on the A391 at Carn Grey, located on the A391 to the east of the A391 / Carclaze Road roundabout. The graph shows traffic flows in August are more than 15% higher than those in May (a ‘neutral month’). The graph also shows the Annual Average Daily Traffic (AADT), which shows how flows vary around the daily mean.
2.3.2 Figure 7 shows the hourly flow profile for 2-way traffic on the A391 at Carn Grey, in terms of neutral and summer months. The figure shows that for neutral months, there is an increase in two way traffic flows around the PM peak, especially between 3pm and 6pm. The AM peak is less noticeable; flows during this period are similar to those experienced during the interpeak period. Flows generally decrease to lower levels in the evening. In the summer, the flows are lower than neutral months between 7am and 9am, suggesting a decrease in commuting traffic. However, for the rest of the day, the flows observed are noticeably higher than neutral months.
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Figure 6 – Monthly Flow Profile on the A391 at Carn Grey
Figure 7 – Hourly Flow Profile on the A391 at Carn Grey
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2.4 Summary
2.4.1 The analysis of traffic data shows that traffic volumes are very high on the A390 through St. Austell, with traffic flows exceeding 21,000 vehicles (2 way) over a 12-hour (7am to 7pm) period. This volume of traffic results in frequent congestion and delays on this route; this is supported by anecdotal evidence from the area.
2.4.2 Traffic volumes are also high on the A391 and Par Moor Road, both of which experience flows greater than 13,000 vehicles over a 12-hour period (7am to 7pm).
2.4.3 Traffic flows in St. Austell increase significantly during the summer period, with flows in August more than 15% higher than those in neutral months.
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3 FUTURE DEVELOPMENT
3.1 Introduction
3.1.1 The Regeneration Plan identifies a number of sites within the St. Austell, gleaned from responses to a ‘call for sites’, which may be able to deliver the type of transformational regeneration that is outlined in the plan. These include of a number of sites that form part of the eco-communities, as well as other sites within the area.
3.1.2 A plan showing the largest of these potential development sites is shown in Figure 8 below:
Eco-Communities
Other Developments
Goonbarrow
Drinnick Baal & West Carclaze
St Austell Northern Extension Blackpool
Par Docks Coyte Farm
Carlyon Bay Pentewan Rd
Figure 8 – Future Development Sites in the St. Austell Area
3.2 Eco Communities
3.2.1 The eco-community developments aim to provide highly sustainable developments that can regenerate the St. Austell, St. Blazey and China Clay area. The developments will re-use former china clay extraction sites, and due to the location of these sites, will provide a series of inter-connected settlements, each specifically designed to integrate with the surrounding landscape and settlements, and link to the other sites and St. Austell itself. The new developments will include housing and employment development, alongside leisure and community facilities within walking distance, to encourage exemplar sustainability standards. The green ethos of the sites intends to ensure an ‘environment first’ approach, with green and open spaces at the heart of the developments; this is apparent in the masterplan sketch shown in Figure 9.
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Figure 9 – Masterplan for West Carclaze / Baal Eco-Community (source: EcoBos)
3.2.2 The eco-community sites could provide the majority of development within the St. Austell over the next 20 years. The proposed development within each site is detailed below:
Residential Employment 2 (dwellings) (m )
West Carclaze / Baal 2,000 18,262
Blackpool 1,850 16,892
Par Docks 450 4,109
Goonbarrow 500 4,565
Drinnick 200 1,826
Table 2 – Eco-Community Developments
3.2.3 The scale of development indicated above is likely to vary as proposals are brought forward, but the figures represent the best available information at present.
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3.3 Development Phasing
3.3.1 Potential developments have been identified as examples of proposals that could regenerate the area over the next 20 years, in line with the Regeneration Plan and Connecting Cornwall policies. Construction of the development will therefore be phased over this period – a summary of the possible phasing plan is shown in the table below:
Eco Community Development Other Developments Years Modelled Year Residential Employment Residential Employment Eco Town Development Retail (sqm) (dwellings) (sqm) (dwellings) (sqm) 2012 (Pilot Phase) 2012 Baal + West Carclaze 100 1793 Goonbarrow Refinery 0 0 Pentewan Road 0 0 5110 Drinnick 0 0 St Austell Northern 500 3462 2013 - 2015 2015 Baal + West Carclaze 500 3686 Extension Blackpool 0 0 Carlyon Bay 500 0 0 Par Docks 0 0 Goonbarrow Refinery 0 0 St Austell Northern 800 5538 0 Drinnick 0 0 Extension 2015 - 2020 2020 Baal + West Carclaze 700 6392 Coyte Farm 623 4442 12327 Blackpool 500 4565 Par Docks 300 2739 Goonbarrow Refinery 50 457 Drinnick 50 457 2020 - 2025 2025 Baal + West Carclaze 600 5479 Blackpool 650 5935 Par Docks 150 1370 Goonbarrow Refinery 450 4109 Drinnick 150 1370 2025 - 2030 2030 Baal + West Carclaze 100 913 Blackpool 700 6392 Par Docks 0 0
Table 3 – Development Phasing
3.3.2 The identified developments represent potential development that could come forward in the St. Austell area. This allows potential future development within the area to be represented in the traffic model, to ensure that future traffic generation is not under represented. This scenario represents one of a number of possible scenarios that could occur; additional scenarios can be modelled as sensitivity tests within the traffic model. For each of the identified developments, traffic generation has been calculated using appropriate trip rates, either agreed with Cornwall Council officers or extracted from the developments Transport Assessments.
3.4 Sustainability
3.4.1 The trip generation from the Eco Community developments has been calculated for two scenarios; one assuming a level of trip generation consistent with other developments of this type and location (termed standard trip generation in this report), and another lower level of trip generation with a higher level of sustainable travel assuming that the travel plan and sustainability measures incorporated as part of the eco development ethos are successful in reducing travel by non sustainable modes (termed sustainable trip generation). By representing both scenarios in the modelling assessments, the impact of not achieving the sustainable travel targets can be determined and analysed.
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4 ECO-COMMUNITY TRANSPORT SCHEMES
4.1 Introduction
4.1.1 The objective of the eco-communities is to achieve high standards of sustainable living, by encouraging residents to live and work in the local area and providing access to sustainable travel. Planning these developments therefore includes the production of a series of strategies with the aim of meeting the objectives of the eco-communities, including bus, walking and cycling strategies. This document details the associated highways strategy, identifying focussed improvements on the highways network that may be required.
4.2 Eco-Community Transport Schemes
4.2.1 The planning of the eco-communities also includes the development of a comprehensive Travel Plan, which will detail the strategy to reduce the need for travel and to maximise travel by sustainable modes. This strategy includes the provision of a number of measures to promote sustainable travel, including walking, cycling and public transport measures. A full list of the measures within the Travel Plan is included in Appendix 1.
4.3 Park and Ride
4.3.1 The sustainable transport strategy proposals include new Park and Ride services to provide a sustainable travel mode for access to major destinations within St. Austell. These Park and Ride sites will be located close to the new eco-communities where possible, to allow integration with these developments and easy access to sustainable travel for residents in these areas. Studies are currently being undertaken to assess the practicality and viability of Park and Ride sites on the northern and eastern sides of St. Austell; a western site is also possible.
4.3.2 Transfer of car trips to bus is also possible through Pocket Park and Ride schemes; these are small sites located bear to existing bus services. The impacts of these will be of a smaller scale, but it is hoped that several sites can be found providing cumulative relief to the network.
4.4 Highways Schemes
4.4.1 The objective of the eco-communities is to provide exemplar developments in terms of the environment and sustainability, and therefore the developments aim to achieve very high standards of sustainable travel, by reducing the need for travel and achieving high levels of walking, cycling and travel by sustainable modes. The eco-communities will aim to achieve 50% of travel by sustainable modes; however, given the size of the developments that are planned, as well as other developments within the St. Austell area, there will be an impact on the highways network due to traffic generated from the sites. There will therefore be a need for improvements to the highways network, in order to ensure that the network continues to operate at an acceptable level and that strategic routes maintain the required level of service. The development impact, possible improvement schemes and when these may be required are detailed in Section 6 of this report.
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5 ST. AUSTELL AREA TRANSPORT MODEL
5.1 Introduction
5.1.1 The impact of possible future developments in the St. Austell area outlined in the Regeneration Plan on the highway network has been assessed using a detailed transport model. The model represents the highway network within the St. Austell area and the principal roads connecting the town to the surrounding areas. This has been developed using the SATURN2 highway modelling software suite; detailed information on the transport model can be found in the Local Model Validation Report and Forecasting Report.
5.1.2 The traffic model allows detailed assessment of the impacts of developments on the network in the modelled area, both in terms of their individual and cumulative impacts. Given that the model covers a wide study area incorporating the whole of St. Austell and much of the surrounding area, the impacts of developments on the wider network can also be analysed. This allows appropriate mitigation measures over this wider area to be identified and assessed. This process can provide valuable information as there is often a lack of knowledge of the wider impact of developments and measures that may be required to be brought forward to mitigate the impact. The traffic model can identify the key areas of impact, and with associated detailed junction models, may determine acceptable solutions. The model therefore provides a tool that can be used both during this project and in the assessment of future development proposals that may come forward in the area.
5.2 Base Year Model
5.2.1 The base year traffic model was constructed by creating a matrix of vehicle trips within the modelled area. This matrix contains information regarding the origin, destination and purpose of each trip within the modelled time period. The trip matrix was constructed from a series of roadside interview traffic surveys in the area, which were carried out in September 2010. These interviews involved stopping vehicles at the site of the road in a number of locations, and asking drivers questions regarding their origin, destination, journey purpose and journey frequency.
5.2.2 Each trip within the origin / destination trip matrix is assigned a route though the modelled highway network. The base year modelled network contains all major highway links within the modelled area. All links are coded into the model with specific lengths and capacities, and junctions are included in detail, including information regarding the junction type (i.e. signalised, roundabout or priority), geometry and lane usage. The modelled network in and around St. Austell is shown in Figure 10. Once all trips in the matrix have been assigned a route, the route choice of all trips is combined to determine traffic flows on each road represented by the model during the modelled time periods.
2 Simulation and Assignment of Traffic in Urban Road Networks
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China Clay Area St. Blazey
St. Austell
Figure 10 – Screenshot of St. Austell Area Transport Model
5.2.3 The inclusion of detailed link and junction information allows delays experienced due to queues and congestion to be calculated by the model, and incorporated in the route assignments. This allows existing conditions to be accurately replicated in the model.
5.2.4 This base year traffic model is calibrated to Department for Transport (DfT) standards by comparing modelling flows to observed data, to ensure traffic flows produced by the model accurately represent existing conditions within the town. In addition, modelled journey times on key routes are also compared to observed data to ensure travel times are also accurately represented.
5.3 Forecasting
5.3.1 The calibrated base year traffic model is used as the basis to forecast future traffic flows and conditions within St. Austell and the surrounding area. This process includes a calculation of future traffic demand by analysing traffic growth occurring due to predicted future residential and employment development as well as assessing the impact of future fuel prices, car ownership levels and growth in the economy. Traffic flows can be forecast for a number of possible scenarios for the town in terms of development and infrastructure improvements. By calculating future demand levels for each scenario, it is possible to assess the location and likely cause of potential congestion, along with testing the effectiveness of any proposed solutions.
5.3.2 The future year forecasts allow the impact of specific developments on the network to be assessed in detail, to determine the level of development than can be accommodated and mitigation measures that are required.
5.3.3 The assessment of the impact of the eco-community developments on the transport network will include sensitivity tests to analyse the effect of varying development trip rates. This allows the impact of the developments to be assessed if high levels of sustainable travel are achieved, but also with higher trip rates representing increased levels of traffic generation (a level that would be typical for a non eco-community development).
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5.4 Scheme Assessments
5.4.1 Alongside the strategic transport model, a number of detailed junction models have been constructed to allow key junctions to be modelled in a high level of detail. This allows the performance of these junctions to be assessed throughout the phasing of the developments, which in turn allow the trigger points for improvement to be determined. The models were also used to assess the performance of possible improvement options.
5.5 Summary of Modelling Methodology
5.5.1 The modelling methodology is summarised below:
Base Year Traffic Survey Trip Matrix Data Validated Base Year Transport Model Existing Road Existing Travel Network Patterns Data
Future Background Developments Traffic Growth Future Year Transport Model Future Transport Development Schemes Trip Rates
Future Traffic Key Junction Scheme Flows Appraisal Assessments
Network Queuesand Performance Delays
Figure 11 – Summary of Transport Modelling Methodology
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6 INFRASTRUCTURE PHASING
6.1 Introduction
6.1.1 The assessments of future developments using the transport model has allowed the impact of each phase of the development on the highway network to be determined, and key infrastructure improvements and the trigger points of these to be identified. This section details the key impacts of each phase of the development and what infrastructure may required at each phase to mitigate the development impact. The development included within each phase is detailed in Section 3.2.3.
6.1.2 The number of possible scenarios is great. This report attempts to introduce improvements and mitigation measures in a rational way that address the problems that might occur as the scenarios develop. The assessment of the affordability, viability and environmental and social acceptability of proposals are beyond the scope of this study.
6.2 Standard Trip Rate Assessment
6.2.1 A summary of the key outputs from the assessments using standard trip rates is detailed in the following sections. A PowerPoint presentation of this strategy has been produced showing the outputs from each modelled time period and future year; the slides from this are included in Appendix 2.
2013
6.2.2 The pilot phase of the eco community developments is scheduled to be completed by 2013. The traffic generated from this development primarily impacts on the Carluddon double mini roundabouts; the modelling predicts that the additional traffic will result in the junction reaching capacity. Therefore, any further development would result in this junction operating above capacity, and would result in a key constraint on the A391 strategic route from St. Austell to the A30. It is therefore recommended that little further development beyond the pilot phase should be occupied on the West Carclaze / Baal site until the A391 West Carclaze Diversion (WCD) is constructed. This scheme removes traffic from Carluddon mini-roundabouts junction ensuring this operates within capacity, and hence ensures that the function of the A391 as a strategic route is maintained. The impact of the A391 West Carclaze Diversion scheme is shown in Figures 12a and 12b (which are taken from the presentation in Appendix 2).
6.2.3 The construction of the A391 West Carclaze Diversion releases the current capacity restraint on this section of the A391 caused by the Carluddon double mini roundabouts. Releasing this constraint causes some traffic that currently uses alternative routes avoiding this section of the A391 to be attracted back to the A391 route; therefore traffic flows on the A391 increase as a result of the WCD scheme. This increase in traffic causes congestion on the A391 northern approach to Scredda Roundabout; it is therefore recommended that widening of this northern section should occur at this stage (details of this scheme are shown in Section 7.2).
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Ref 133 15 Figure 12a – 2013 AM Peak With and Without A391 WCD
16 18 Figure 12b – 2013 PM Peak With and Without A391 WCD
3 The references refer to the page number of the diagram in the presentation included in Appendix 2 Prepared by Parsons Brinckerhoff September 2011 Page 21 for Cornwall Council ST. AUSTELL AREA HIGHWAYS STRATEGY TRANSPORT MODELLING REPORT
2015
6.2.4 In 2015, further development of the West Carclaze / Baal eco-community site is proposed, along with development at the St Austell Northern Extension, Coyte Farm and Carlyon Bay sites within the St. Austell area. This results in increased traffic demand on the highways network, and causes a reduction in performance of some junctions; particularly on routes from the West Carclaze / Baal site into St. Austell. The junctions on the A391, including the improved Scredda Roundabout have sufficient capacity to accommodate the increase in traffic flows; however the Slades Road / Polkyth Road junction will experience increased congestion and hence improvement to this junction is recommended (details of a possible scheme are shown in Section 7.4). The additional traffic from these developments also causes some adverse impact on the junctions on the A390, primarily at the double mini roundabouts and ASDA junctions.
2020
6.2.5 The phasing plan for the eco-community developments shows a considerable increase in development in the period from 2015 to 2020, including further development of the West Carclaze / Baal site (including an additional 700 houses), and initial development of the Blackpool and Par Docks sites. This development puts increased pressure on the transport network, particularly on the routes into St. Austell from the development sites, including the A391 from the north, and A390 and Par Moor Road from the east. In order to reduce demand on the highway network, it is recommended that the Park and Ride sites are implemented at this time; in particular the eastern park and ride site reduces traffic demand on the A390 from the east, resulting in an improvement in the performance of Britannia Roundabout. The modelling work predicts that Carclaze Roundabout on the A391 would operate above capacity at this time, and hence some improvement to this junction is also recommended (details of a possible scheme are shown in Section 7.3). Again, the additional traffic puts pressure on the junctions along the A390 to the south of the town, particularly ASDA junction; however, improvements to the operation of this junction appear difficult.
6.2.6 The impact of the proposed improvements is shown in Figures 13a and 13b (taken from Appendix 2).
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Figure 13a – 2020 AM Peak With and Without Improvements
25 27
Figure 13b – 2020 AM Peak With and Without Improvements
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2025
6.2.7 By 2025, further development occurs at the West Carclaze / Baal, Blackpool and Par Docks sites, alongside additional development at Goonbarrow and Drinnick. In particular, significant development occurs at Blackpool, which results in increased traffic on the A3058 route from Blackpool to St. Austell, causing significant congestion at the A3058 signalised junction. This congestion causes some traffic to use alternative routes to travel to St. Austell town centre, including the A391. In addition, the access route from Blackpool to the north joins the A391 at Singlerose Roundabout where congestion is also predicted, although this access junction may be able to be designed to a higher standard. The severe congestion on the A3058 into St. Austell from the west suggests that the Trewoon Bypass and Southern Distributor Road would be beneficial at this stage in order to mitigate this impact. The development, and the release of the A3058 signalised junction constraint provided by Trewoon Bypass, causes increased congestion on other junctions along the A390, including the ASDA Roundabout and Mount Charles Roundabout. Improvements to increase capacity at the double mini-roundabouts and ASDA Roundabout appear difficult, although some improvements should be possible at Mount Charles Roundabout, as shown in Section 7.5.
6.2.8 The impact of Trewoon Bypass, Southern Distributor Road and improvements at Mount Charles Roundabout are shown In Figures 14a and 14b (taken from Appendix 2).
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28 30
Figure 14a – 2025 AM Peak With and Without Improvements
31 34
Figure 14b – 2025 PM Peak With and Without Improvements
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2030
6.2.9 By 2030, the full development at each of the eco-community sites is scheduled to be complete, which includes a total of 5,000 dwellings at all the sites, along with 45,654m2 of employment space. The developments generate additional traffic demand on the highway network, which causes increased congestion in some areas, particularly on the A390 to the south of St. Austell, and the northern section of the A391 from Singlerose Roundabout through Bugle, which is of a lower standard to the southern section (consisting of the new West Carclaze Diversion route and the North East Distributor Road). At this stage, the northern section of the A391 route would provide a higher standard route, ensuring that the A391 continues to function as a strategic route from St. Austell to the A30. In addition, the new route would provide a bypass to Bugle and Stenalees, and ensure that the junctions within these towns operate within capacity. The impact of the A391 northern section is shown in Figures 15a and 15b (taken from Appendix 2).
6.2.10 The western park and ride site would also be beneficial at this stage, in order to provide a sustainable mode of transport to destinations within St. Austell, and reduce traffic on the existing A390 and Southern Distributor Road.
6.2.11 The full development included in the 2030 scenario generates additional traffic on the A390 to the south of St. Austell. However, the improvements identified in the strategy would provide mitigation of this impact and would improve the performance of a number of junctions on this route ensuring that they operate within capacity. The exception to this is at Mount Charles Roundabout and ASDA roundabout where the junctions are predicted to operate at or above capacity in 2030; further improvement at these junctions may be difficult. With the identified improvements, the level of performance of the A390 route would not be expected to be significantly worse than the present day, particularly if the lower trip rates aspired to in the sustainable development scenario are achieved (as detailed in Section 6.4).
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Figure 15a – 2030 AM Peak With and Without Improvements
38 39
Figure 15b – 2030 PM Peak With and Without Improvements
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6.3 Summary of Strategy
6.3.1 The infrastructure improvements identified within the strategy aim to ensure that the impact of possible future developments on the highway network is minimised, and that key routes maintain their function as strategic routes connecting St. Austell to the trunk road network at the A30 and other towns. The highway improvements are intended to be focussed and ensure that key sections of the network are improved when possible. It should be recognised that these improvements form part of an integrated sustainable transport strategy, alongside the bus, walking and cycling strategies, and form part of the overall travel plan for the developments. The travel plan aims to ensure the development is as sustainable as possible, in line with the ethos of eco-communities; should the demand for vehicular travel be reduced to that of the aspirations of eco- communities, some of the identified improvements may not be required. There should therefore be an aim to encourage sustainable travel to limit the level of investment required in the highways network.
6.3.2 The development and infrastructure phasing detailed in the previous paragraphs is summarised in Figures 16 and 17, the latter showing the estimated costs of some schemes at 2010 prices.
6.4 Sustainable Trip Generation Assessment
6.4.1 A comprehensive travel plan has been produced for the first of the eco-community sites to outline the proposed initiatives and measures to support the sustainable travel ethos of the sites and to maximise travel by sustainable modes (as detailed in Section 4.2). The travel plan aims to reduce car based travel and achieve 50% of travel by sustainable modes.
6.4.2 In the traffic model, the impact of the travel plan has been modelled through reduced vehicle trip rates. The model has been used to assess the impact of this sustainable trip generation scenario, to determine the level of impact should the sustainable travel targets be achieved at each of the eco-community sites.
6.4.3 Given the level of development associated with the eco-community sites, the volume of traffic generated from the development would still have an impact on the surrounding road network that would require mitigation to ensure that the highway network continues to operate effectively. However, the assessment of the sustainable trip generation scenario shows that some of the identified highways mitigation measures may not be necessary if the travel plan measures are effective in reducing car based travel at all the eco-community sites. The key outputs from these assessments show that:
x The improvement scheme at Carclaze Roundabout that would be required in 2020 would not be required, as the roundabout is predicted to operate within capacity in 2030;
x The Slades Road / Polkyth Road junction may not be required, as the junction would operate at capacity in 2030, compared to above capacity with the standard trip rate scenario;
x The Northern A391 improvement may not be required in purely transport terms. With the sustainable trip rate scenario, Singlerose Roundabout and the Bugle signalised junction would reach, but not exceed, capacity (as with the standard trip rate scenario), although some congestion would still be experienced at peak times;
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x The other identified improvement schemes would still be required to mitigate the impact of the traffic generated by the development.
Development Base Year Infrastructure
Dwellings: 100 (WCB), 500 (St. A NE) - A391 West Carclaze Diversion Employmt: 1793m2 (WCB), 3462m2 (St. A NE) 2013 - Scredda Roundabout Improvement Retail: 5,110m2 (Pentewan Road)
Dwellings: 600 (WCB), 800 (St. A NE), 623 (Coyte), 500 (Carlyon) - Slades Rd / Polkyth Rd junction improvement* Employmt: 5479m2 (WCB), 5538m2 (St. A NE) 2015 4442m2 (Coyte) Retail: 12,327 (Coyte Fm)
Dwellings: 1300 (WCB), 500 (BP), 300 (Par) - Eastern Park and Ride - Northern Park and Ride Employmt: 11870m2 (WCB), 4565m2 (BP), 2020 - Blackpool access roads 2739m2 (Par) - Carclaze Roundabout Improvement*
Dwellings: 1900 (WCB), 1150 (BP), 450 (Par) - Trewoon Bypass 50 (GB), 50 (Dr) - Southern Distributor Road Employmt: 17349m2 (WCB), 10501m2 (BP), 2025 - Mount Charles Roundabout improvement 4109m2 (Par), 457m2 (GB), 457m2 (Dr)
Dwellings: 2000 (WCB), 1850 (BP), 450 (Par) 500 (GB), 200 (Dr) - Western Park and Ride Employmt: 18262m2 (WCB), 16892m2 (BP) 2030 - Northern A391 Improvement* 4109m2 (Par), 4565m2 (GB), 1826m2 (Dr)
* Improvement may not be required if sustainable trip generation levels achieved
Key: WCB = West Carclaze / Baal, Par = Par Docks, BP = Blackpool, GB = Goonbarrow, Dr = Drinnick, St. A NE = St. Austell Northern Extension, Coyte = Coyte Farm
Figure 16 – Summary of Strategy
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Figure 17 – Diagrammatic Summary of Strategy
6.4.4 Table 4 below shows the cost estimates for each of the improvements in the strategy, where available.
Year Improvement Cost Estimate
A391 West Carclaze Diversion including 2013 £10m Scredda Roundabout improvement 2015 Slades Rd / Polkyth Road improvement TBC 2020 Eastern Park and Ride £10m Northern Park and Ride £8m Blackpool Access Roads £30m Carclaze Roundabout improvement TBC 2025 Trewoon Bypass £10m Southern Distributor Road £9m Mount Charles Roundabout improvement TBC 2030 Western Park and Ride £10m Northern A391 improvement £48m
Table 4 – Cost Estimates for Strategy Improvements
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7 HIGHWAYS IMPROVEMENT SCHEMES
7.1 Introduction
7.1.1 The assessments have identified that a number of improvements schemes may be required to mitigate the impact of the developments on the highways network. These improvements include a number of major highways schemes (such as the A391 West Carclaze Diversion, Trewoon Bypass, Southern Distributor Road and the A391 Northern Section) as well as a series of junction improvement schemes. Some of these scheme may not be required should the sustainable trip generation targets be achieved (as detailed in Section 6.4). The required junction improvements and possible schemes are detailed in the following sections.
7.1.2 Other possible traffic reduction measures are also being developed for consideration. These may include bus priority measures at specific junctions to improve journey times and reliability of key bus services. Assessments of these proposals will consider the impact on the surrounding road network and highway capacity.
7.2 Scredda Roundabout
7.2.1 The assessments identify that the A391 northern approach to Scredda will operate above capacity in 2013, following the construction of the A391 West Carclaze Diversion scheme. This is due to the additional traffic generated by the West Carclaze / Baal pilot phase, but also due to the increased capacity of the A391 route and the removal of the capacity constraint at the Carluddon double mini roundabouts attracting traffic back to the A391. By 2030, a further improvement may also be required on the Treverbyn Road approach to the junction, although this would not be required if the sustainable trip generation levels were achieved. A possible improvement scheme is shown below:
A391 (N) Widening to provide 2 lane approach (one ahead and one right) - no widening on exit required
Widening to provide 2 lane approach (one left and one right) - no widening on exitsrequired Entrance to Carclaze Ind. Estate (not shown in aerial photograph)
Treverbyn Road A391 (S)
Figure 18 – Scredda Roundabout Improvements
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7.3 Carclaze Roundabout
7.3.1 The assessments identify that the A391 northern approach to Carclaze Roundabout will operate above capacity in 2020 during the PM peak period. A possible improvement scheme to increase capacity on this approach is shown below:
Widening to provide 2 lane approach (with 2 ahead lanes) - widening on exit required to provide merge A391 (N)
Carclaze Road A391 (S)
Figure 19 – Carclaze Roundabout Improvements
7.4 Slades Road / Polkyth Road Junction
7.4.1 The assessment identifies that improvements to the Slades Road / Polkyth Road junction may be required in 2015 with the standard trip rate scenario. Improvement to the junction may be difficult due to the limited space for widening on the approaches, and difficulties with the alignment from Slades Road to Clifden Road. However, some improvement may be possible by making use of some of the space to the north-west of the junction (as shown in Figure 20); however this space currently consists of a cycleway so alternative cycle provision would be required.
7.5 Mount Charles Roundabout
7.5.1 The analysis of Mount Charles Roundabout suggests that the Mount Charles Road and A390 eastern approaches will operate above capacity from 2025 onwards. Improvements would therefore be required to these two approaches; possible improvements are shown in Figure 21 on the following page.
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Slades Road Widening to provide ahead and right turn lanes on approach
Stopline moved forward to reduce intergreens
Sandy Hill
Polkyth Road
Widening to provide separate left and right turn lanes on approach Rephasing of signals to increase capacity
Figure 20 – Slades Road / Polkyth Road Junction Improvements
Mount Charles Road A390 (E)
Extension of second lane Widening to provide flare on approach separate ahead and right turn lanes
Charlestown Road
A390 (W)
Figure 21 – Mount Charles Roundabout Improvements
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8 SUMMARY
8.1 Introduction
8.1.1 This report details the outcomes from the modelling assessment of the impact of the eco-communities and other potential future developments on the highways network in the St. Austell area. The report provides a strategy for highways improvements to mitigate the impact of the developments.
8.2 Existing Conditions
8.2.1 Congestion is currently experienced on a number of routes in the St. Austell area on a regular basis. Congestion is particularly severe on the A390 to the south of the town, which serves as a through route from the east and north to Truro as well as providing access to a number of locations within St. Austell town centre, and the A391 to the north of Scredda. Traffic flows in St. Austell increase significantly during the summer period, with flows in August more than 15% higher than those in neutral months.
8.3 Future Conditions
8.3.1 The level of traffic generated from the eco-communities and other potential developments within the St. Austell will have an impact on the highways network in the area. The impact will cause increased congestion in some areas, and some mitigation measures will be required to ensure that routes continue to function effectively and provide the required level of service. The travel plans for the eco-community developments intend to provide a framework to encourage sustainable travel and minimise the impact on the highway network, although some improvement measures will still be required.
8.4 Development and Infrastructure Phasing Strategy
8.4.1 The assessment of the impact of the phases of the eco-community development and other developments within the St. Austell has allowed required key infrastructure improvements to be identified, as well as trigger points for their implementation.
8.4.2 The key infrastructure improvements included within the strategy are:
x A391 West Carclaze Diversion; x Blackpool link roads; x Trewoon Bypass; x Southern Distributor Road; x A391 Northern Section*; x Park and Rides on the Northern, Eastern and Western sides of St. Austell (although further analysis is being carried to assess the viability of these sites); x Junction improvements to Scredda Roundabout, Slades Road / Polkyth Road signalised junction*, Carclaze Roundabout* and Mount Charles Roundabout. 8.4.3 If the sustainable measures and initiatives outlined in the eco-community travel plans are effective in reducing travel by car based modes, then some of the improvement schemes detailed above (shown with an asterisk) may not be required in transport terms.
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8.4.4 The highways strategy identified in this document forms part of an integrated transport strategy, alongside the bus, walking and cycling strategies. These strategies, along with development travel planning, should aim to maximise sustainable travel in accordance with the ethos of eco-communities. Achieving or exceeding aspirations for sustainable development may result in some improvements to the highways network not being required.
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Appendix 1
1 2 3 4 5
Appendix 2
St. Austell Transport Modelling Infrastructure Phasing
September 2011 Study Area
A30
A390
A391
A30
A390 Study Area
A30
Lockengate
A390 Bugle A391 Stenalees Penwithick
Carluddon Par & St. A30 Blazey Trewoon
St. Mewan St. Austell A390 Development Phases
2010 AM Total Dwellings - Baal & West Carclaze: 100 2013 PM
2015
2020
2025 Baal & West Carclaze Pilot Phase 2030
Total Employment Floorspace (sqm) - Baal & West Carclaze: 1,793 Development Phases
2010 AM Total Dwellings - Baal & West Carclaze: 100 600 2013 PM
2015
2020
2025
2030
Total Employment Baal & West Floorspace (sqm) Carclaze - Baal & West Carclaze: 1,793 5,479 Development Phases
2010 AM Total Dwellings - Baal & West Carclaze: 600 1,300 2013 PM - Blackpool: 500 - Par Docks: 300 2015
2020
2025
2030
Total Employment Floorspace (sqm) Blackpool - Baal & West Carclaze: 5,479 11,870 - Blackpool: 4,565 - Par Docks: 2,739 Par Docks Development Phases
2010 AM Total Dwellings - Baal & West Carclaze: 1,300 1,900 2013 PM - Blackpool: 500 1,150 - Par Docks: 300 450 - Goonbarrow: 50 2015 - Drinnick: 50
2020 Goonbarrow 2025
2030 Drinnick
Total Employment Floorspace (sqm) - Baal & West Carclaze: 11,870 17,349 - Blackpool: 4,565 10,501 - Par Docks: 2,739 4,109 - Goonbarrow: 457 - Drinnick: 457 Development Phases
2010 AM Total Dwellings - Baal & West Carclaze: 1,900 2,000 2013 PM - Blackpool: 1,150 1,850 - Par Docks: 450 - Goonbarrow: 50 500 2015 - Drinnick: 50 200
2020
2025
2030
Total Employment Floorspace (sqm) - Baal & West Carclaze: 17,349 18,262 - Blackpool: 10,501 16,892 - Par Docks: 4,109 - Goonbarrow: 457 4,565 - Drinnick: 457 1,826 Development Overview
Goonbarrow
Drinnick
Blackpool Baal & West Carclaze
Par Docks Junction Study Area
A391
Bugle Jct.
Carluddon Singlerose Rbt. Double-Mini Rbts.
Menear Rbt. Scredda Rbt. Trenowah Rbt. Carclaze Rbt. A390 / A391 Jct. Treverbyn Rd. / Slades Rd. Signals Britannia Rbt. Slades Rd. / Polkyth Rd. Signals Bucklers Lane Jct. A3058 / B3274 Signals Holmbush Arch Rd Jct.
A390 Double-Mini Rbts. Daniels Lane Jct. Porthpean A390 Sawles Rd. Jct. ASDA Rbt. Rd Signals Mount Charles Rbt. Junction Performance
2010 AM Base
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM Base
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM Without WCD
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With WCD
2013 PM
2015
2020
2025 Great Treverbyn Rbt.
2030 Staggered Jct.
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With WCD
2013 PM
2015
2020
2025
2030
Scredda Rbt Improvement Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM Without WCD
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With WCD
2013 PM
2015
2020
2025 Great Treverbyn Rbt.
2030 Staggered Jct.
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With WCD
2013 PM
2015
2020
2025
2030
Scredda Rbt Improvement Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching Slades Rd / Polkyth Rd Jct. Improvement (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching Slades Rd / Polkyth Rd Jct. Improvement (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM
2013 PM
2015
2020
2025 Blackpool Access Roads. 2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM
2013 PM
2015
2020 Northern P&R 2025
2030
Junction Capacity Key Eastern P&R = Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM
2013 PM
2015
2020 Northern P&R 2025
2030
Junction Capacity Key Eastern P&R = Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM
2013 PM
2015
2020
2025
2030
Carclaze Rbt Improvement Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM Without Trewoon Bypass
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With Trewoon Bypass
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With Trewoon Bypass and 2013 PM Southern Distributor
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM Without Trewoon Bypass
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With Trewoon Bypass
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With Trewoon Bypass
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%) Mount Charles Rbt Improvement = Over (> 100%) Junction Performance
2010 AM With Trewoon Bypass and 2013 PM Southern Distributor
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%) Mount Charles Rbt Improvement = Over (> 100%) Junction Performance
2010 AM Without A391 Improvements
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With A391 Improvements
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With A391 Improvements
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%) Western P&R
= Over (> 100%) Junction Performance
2010 AM Without A391 Improvements
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Junction Performance
2010 AM With A391 Improvements
2013 PM
2015
2020
2025
2030
Junction Capacity Key
= Within ( 85%)
= Approaching (> 85% & < 100%)
= At (= 100%)
= Over (> 100%) Infrastructure Phases
2010 AM
2013 PM
2015
2020
2025
2030
West Carclaze Distributor Road
Scredda Rbt Improvement Infrastructure Phases
2010 AM
2013 PM
2015
2020
2025
2030
Slades Rd / Polkyth Rd Jct. Improvement Infrastructure Phases
2010 AM
2013 PM
2015
2020
2025
Northern Park & Ride 2030 Blackpool Access Roads
Carclaze Rbt Improvement
Eastern Park & Ride Infrastructure Phases
2010 AM
2013 PM
2015
2020
2025
2030
Trewoon Bypass
Mount Charles Rbt Improvement
Southern Distributor Infrastructure Phases
2010 AM
2013 PM
2015
2020
2025 A391 Improvements
2030
Northern Park & Ride Infrastructure Overview
A391 Improvements (£48m)
Northern Park & Ride (£8m)
Blackpool Access Roads (£30m) West Carclaze Distributor Road (£10m)
Scredda Rbt Improvement Carclaze Rbt (included in WCD Cost) Improvement (TBC)
Slades Rd / Polkyth Rd Jct. Improvement (TBC)
Trewoon Bypass (£10m) Eastern Park & Ride (£10m) Western Park & Ride (£10m) Mount Charles Rbt Improvement (TBC) Southern Distributor (£9m)