TECHNICAL NOTE 8(v2): MAIN STREET STRATEGY

Transcription

1 SCOTT WILSON SHERFORD, PLYMOUTH TECHNICAL NOTE 8(v2): MAIN STREET STRATEGY Ref: D CAR19 August 2007

2 SHERFORD, PLYMOUTH Technical Note 8 (v2): MAIN STREET STRATEGY Collated and edited by: Reviewed by: Approved by: Kevin Kay Senior Transport Consultant Kevin Kay Senior Transport Consultant Sandy Burrell Technical Director Scott Wilson Scott House Basing View Basingstoke RG21 4JG Tel: +44 (0) Fax: +44 (0) Disclaimer This document has been prepared in accordance with the scope of Scott Wilson's appointment with its client and is subject to the terms of that appointment. It is addressed to and for the sole use and reliance of Scott Wilson's client. Scott Wilson accepts no liability for any use of this document other than by its client and only for the purposes, stated in the document, for which it was prepared and provided. No person other than the client may copy (in whole or in part) use or rely on the contents of this document, without the prior written permission of the Company Secretary of Scott Wilson Ltd. Any advice, opinions, or recommendations within this document should be read and relied upon only in the context of the document as a whole. The contents of this document are not to be construed as providing legal, business or tax advice or opinion. Scott Wilson Group plc 2006

3 SHERFORD MAIN STREET STRATEGY 1. INTRODUCTION 1.1 In 2006, Scott Wilson (SW) submitted a Transport Assessment (TA) in support of a planning application for the development of a sustainable new community at Sherford, located to the east of the City of Plymouth, in Devon. 1.2 This Technical Note expands on the work undertaken for the TA, in order to confirm the output of the modelling provided and to further assess the implications of high street movements. 1.3 The internal distribution of traffic within Sherford, presented in the TA, was determined with the use of a SATURN model, to allow for vehicular loadings to be established based on available capacity. This ensured a representation of traffic on the Main Street for the purpose of informing the design of the junctions proposed along its length. 1.4 The assignment of traffic presented in the TA was based on the relative relationship between the different road hierarchy types with little account of the additional delays that may be incurred on the Main Street. In discussions with the MWG, a revised approach to the internal distribution of traffic has been devised to support a particular defined routing strategy. 1.5 The aim of this strategy would be to ensure the most appropriate balance of flows, one which would seek to enhance the character of the Main Street as a place without being detrimental to the concept of vibrancy which is contributed to by a certain level of traffic throughput. 1.6 The methodology employed for this note will therefore be to devise a strategy based on alternative flow group, the objective of which would be to act as a marker for progressing determination. This would ensure that sufficient intervention (e.g. through signal settings, etc) can be implemented to shape both the distribution of traffic and allow for sufficient bus priority to be provided. 1.7 The strategy will initially be informed by the TA and the traffic information underlying the junction capacity assessments. The basis for the SATURN assignment will be discussed with regard to the various interventions available with a view to presenting alternative representations of internal distribution. Finally, the implications of adopting a micro-simulation approach to modelling bus priority will be discussed to determine the most appropriate approach in light of current timescales. 30th August

4 SHERFORD MAIN STREET STRATEGY 2. MAIN STREET MODELLING 2.1 TRANSPORT ASSESSMENT The TA presented a scenario for Sherford with an assignment of traffic which was based on the internal highway hierarchy contained within the Masterplan Drawing 038-III/ OPA (15/11/2006). This road hierarchy was coded into a SATURN model of Sherford to allow an assignment of traffic based on the relative difference in road type where it considered the first three road type classifications In the SATURN model, all the main junctions on the Main Street were coded as simulation dummy nodes to allow turning movements to be extracted and inputted into more detailed junction capacity assessments. The remainder of the Sherford network used buffer coding to deal with the peripheral assignment of traffic. The coding methodology, including the zoning used, is described in more detail in the TA FIGURE 2.1 and FIGURE 2.2 show the turning movements along the length of Main Street which were used as the input into the junction capacity assessments presented in the TA. The plots show those junctions which were considered and tested within the TA as well as other more minor junctions along the Main Street. Whilst road types with lower classification were not all modelled explicitly in the SATURN model, some estimation of flow at intermediate points has also been possible in some locations For the main junctions, some extrapolation of flows was made to ensure the most robust scenario for the purpose of capacity testing. For example, selected movements around the Northern Distributor East junction were added to the Southern Distributor East junction. Indeed, FIGURE 2.1 shows how 366 movements were added to the left turn at two locations as a guarantee that any localised reassignment could be accommodated by the junctions The input flows for the Northern Distributor West junction were also obtained from the amalgamation of flows with adjacent junctions to represent a worst-case situation, for the purposes of junction capacity testing. 2.2 TOWN ANALYSIS In determining the level of traffic commensurate with the vibrancy of Sherford, it is useful to establish, by means of comparison, the degree to which other High Streets are considered to be vibrant In developing the case for a self-sustaining and sustainable community, the towns of Honiton and Marlborough were used as examples of what could be achieved in terms of the organic growth of towns and the urban design characteristics necessary to promote an enjoyable and vibrant High Street Traffic flow information on the vehicular throughput for each High Street respectively, has been sourced from the relevant Highway Authorities. These are shown in TABLE 2.1 below: 30th August

5 SHERFORD MAIN STREET STRATEGY TABLE 2.1. Case Study Town Vehicular Throughput Comparison (AM Peak) Link Location Sherford (Central Junction) Peak Factored 12hr 12hr Flow (2006) (2016) Factor (2016) AM PM Marlborough (South End) AM 1392 a c Honiton (W Church Junction) AM 819 b d a 2001 count factored by 1.12 to Year 2006 using TEMPRO/NRTF b 2004 count factored by 1.04 to Year 2006 using TEMPRO/NRTF c Baseline count factored by 1.17 to Year 2016 using TEMPRO/NRTF d Baseline count factored by 1.18 to Year 2016 using TEMPRO/NRTF The comparison shown above illustrates that the level of flow predicted for the Sherford High Street section of the Main Street would be between and which is higher than currently experienced at Marlborough and Honiton The peak to period factors used for Sherford is reasonable when considered against the profile of the other two towns. The source of the peak to period factors are shown in TABLE 2.2. TABLE 2.2. Sources of High Street Peak to Period Factors High Street Link Location Survey Source Sherford Composite Marlborough (South End) Honiton (W Church Junction) Stanborough Cross 2003 Elburton Roundabout 2003 Deep Lane North 2004 Deep Lane South 2004 Wiltshire County Council East Devon District Council Plymouth City Council Plymouth City Council Devon County Council Devon County Council AM Factor PM Factor Average th August

6 Drawing Ref:K:\D Sherford\Drawings\Freehand\Internal Network AM 2016.FH Central Junction Northern Distributor West Southern Distributor West SHERFORD AM 2016 INTERNAL NETWORK Southern Distributor East Key 000 Movements Subject to Sensitivity Testing Tested Junction Movement Location Northern Distributor East New Plymouth Bound Slip Figure: 2.1 Scale at A3: N/A Drawn DW Checked KK Approved GB Date 30/05/2007 Revised Date

7 Drawing Ref:K:\D Sherford\Drawings\Freehand\Internal Network PM 2016.FH Central Junction Northern Distributor West Southern Distributor West SHERFORD PM 2016 INTERNAL NETWORK Southern Distributor East Key 000 Movements Subject to Sensitivity Testing Tested Junction Movement Location Northern Distributor East New Plymouth Bound Slip Figure: 2.2 Scale at A3: N/A Drawn DW Checked KK Approved GB Date 30/05/2007 Revised Date

8 SHERFORD MAIN STREET STRATEGY 3. DEVELOPING A MAIN STREET STRATEGY 3.1 POST-APPLICATION DISCUSSIONS Discussions held during the post-application process have suggested that the levels of traffic flow shown along the Main Street were higher than had been anticipated by the Local Highway Authorities In order to inform these discussions, the relative proportion of flows between the Main Street and the Northern/Southern Avenues have been produced. These are shown in FIGURE 3.1 and FIGURE 3.2 for the AM and PM peaks respectively. The plots show the proportion of traffic between the three routes through Sherford. Under this flow scenario, the Main Street accounts for approximately two thirds of the loadings along the main routes. The corresponding hourly flows for this scenario, are shown in FIGURE 3.3 and FIGURE The assignment of flows was made in the model on the basis of the highway network hierarchy presented in the Masterplan. A sensitivity test was undertaken to show what proportions would be achieved if it was assumed that the speeds on the three routes were equalised. FIGURE 3.5 and FIGURE 3.6 demonstrates that, under this scenario, the proportion of traffic travelling along the Main Street reduces by around 10% over the three routes The corresponding hourly flows for this scenario, shown in FIGURE 3.7 and FIGURE 3.8, indicates that the High Street flow at the Central junction is 1418 for the AM peak, which is equivalent to vehicles from a case study town perspective. 3.2 JUNCTION CAPACITY ASSESSMENTS The assignment of internal vehicular trips was made on the basis of dummy nodes, to allow the most logical loadings to occur across the network. This flow information was input into the detailed junction capacity assessments to establish the workability of the junction designs. In reality, a degree of control will be afforded by junction configuration, the effect of which can be represented in the same way The detailed junction configuration information was input into the SATURN to reflect the effect of junction configuration on the assignment. These sets of signals were also optimised to minimise delay across the network. However, the junction settings which incorporated a bus priority bias were not subject to optimisation (e.g. Stanborough Cross/Haye Road, School Loop) to restrict the ability of the SATURN model to optimise these locations based on a benefit to vehicles By incorporating the detailed junction capacity information, it has no longer been necessary to equalise the speed on the Main Street, as the additional delays created have been replicated in this scenario without being detrimental to the perceived road hierarchy The layout of the SATURN network was also updated during this process to ensure that the results reflected the most recent Main Street designs The full tree for the processes used in developing the SATURN model is shown in FIGURE 3.9. This assessment was undertaken for both the AM and PM peaks in order to set out the markers for re-distribution in both periods. 30th August

9 SHERFORD MAIN STREET STRATEGY FIGURE 3.10 and FIGURE 3.11 shows the proportional loadings of traffic along the Main Street and Northern/Southern Avenues that occur when incorporating the detailed junction coding information within the original SATURN model for all the junctions considered in the TA. FIGURE 3.12 and FIGURE 3.13 shows the absolute link information for the same locations The turning movements associated with the above scenario are shown in FIGURE 3.14 for the AM peak and FIGURE 3.15 for the PM peak. 3.3 REVISED TOWN ANALYSIS The link between traffic flow and High Street vibrancy was established in relation to a selection of case study towns. This comparison is not used to justify levels of traffic on the High Street but to show that vibrancy is also defined in traffic terms In terms of the town analysis, TABLE 3.1 shows a summary of vehicular throughput for the revised AM scenario. TABLE 3.1. Revised Case Study Town Vehicular Throughput Comparison (AM Peak) Link Location Sherford (Central Junction) Period Peak Factored 12hr 12hr Flow (2006) (2016) Factor (2016) AM PM Marlborough (South End) AM 1392 a c Honiton (W Church Junction) AM 819 b d a 2001 count factored by 1.12 to Year 2006 using TEMPRO/NRTF b 2004 count factored by 1.04 to Year 2006 using TEMPRO/NRTF c Baseline count factored by 1.17 to Year 2016 using TEMPRO/NRTF d Baseline count factored by 1.18 to Year 2016 using TEMPRO/NRTF The above comparative table illustrates that by incorporating the detailed junction capacity information the flow predicted for the Sherford High Street section of the Main Street is reduced from the original flow presented in the TA. The absolute flow for the fully signalised Sherford High Street, shown in TABLE 3.1, is illustrated to be lower than that currently experienced at Marlborough and Honiton with an approximate range suggested at between 8,000-11,000 vehicle movements Consultation with the Highway Agency suggested that Marlborough was heavily car-orientated and therefore not a basis for this comparison. Indeed, the High Street proposed for Sherford has significant advantages over Marlborough by virtue of the central running bus lane which emphasises the sustainable hierarchy of modes on which the development was based. The levels of traffic shown above also suggest that Sherford High Street will display lower levels of throughput than Marlborough. 30th August

10 14% 9% 64% 68% 6% 21% 74% Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH11.1 SHERFORD ROUTE SPLITS (SPEED ON HIGH STREET FASTER - AM TOTAL GENERATION) 20% 23% Figure: 3.1 Scale at A4: N/A Drawn DW Checked PK Approved GB Date 23/05/07 Revised Date

11 5% 1% 94% 87% 3% 1% 87% Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH11.1 SHERFORD ROUTE SPLITS (SPEED ON HIGH STREET FASTER - PM TOTAL GENERATION) 10% 12% Figure: 3.2 Scale at A4: N/A Drawn DW Checked PK Approved GB Date 23/05/07 Revised Date

12 Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH SHERFORD ROUTE FLOWS (SPEED ON HIGH STREET FASTER - AM TOTAL GENERATION) Figure: 3.3 Scale at A4: N/A Drawn DW Checked PK Approved GB Date 23/05/ Revised Date

13 Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH11.1 SHERFORD ROUTE FLOWS (SPEED ON HIGH STREET FASTER - PM TOTAL GENERATION) Figure: 3.4 Scale at A4: N/A Drawn DW Checked PK Approved GB Date 23/05/07 15 Revised Date

14 21% 15% 55% 58% 9% 24% 67% Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plotsr.FH11.1 SHERFORD ROUTE SPLITS (SPEED ON HIGH STREET REDUCED - AM TOTAL GENERATION) 24% 27% Figure: 3.5 Scale at A4: N/A Drawn DW Checked PK Approved GB Date 23/05/07 Revised Date

15 15% 13% 62% 64% 7% 23% 71% Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH11.1 SHERFORD ROUTE SPLITS (SPEED ON HIGH STREET REDUCED - PM TOTAL GENERATION) 22% 23% Figure: 3.6 Scale at A4: N/A Drawn DW Checked PK Approved GB Date 23/05/07 Revised Date

16 Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH11.1 SHERFORD ROUTE FLOWS (SPEED ON HIGH STREET REDUCED - AM TOTAL GENERATION) Figure: 3.7 Scale at A4: N/A Drawn DW Checked PK Approved GB Date 23/05/ Revised Date

17 Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH11.1 SHERFORD ROUTE FLOWS (SPEED ON HIGH STREET REDUCED - PM TOTAL GENERATION) Figure: 3.8 Scale at A4: N/A Drawn DW Checked PK Approved GB Date 23/05/ Revised Date

18 NETWORK 1 SATALL ASSIGNMENT PROCEDURE SIMULATION MATRIX NETWORK 2 ASSIGNMENT PROCEDURE SIMULATION OUTPUT CONVERGED Yes No No OUTPUT CONVERGED Yes GREEN TIME OPTIMISATION ASSIGNED NETWORK ASSIGNED NETWORK 1st Pass Drawing Ref:K:\D Sherford\Drawings\Freehand\Drawing Title.FH11.1 FLOW OUTPUT JUNCTION ASSESSMENT (LINSIG / TRANSYT) SHERFORD MAIN STREET STRATEGY PROCESS TREE 2nd Pass MAIN STREET LOADINGS Figure: 3.9 Scale at A4: N/A Drawn DW Checked TE SIGNAL CONTROL Approved KK Date 10/08/07 Revised Date

19 15% 19% 54% 45% 31% 66% Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH11.1 SHERFORD ROUTE SPLIT (FULLY SIGNALISED MAIN STREET - AM TOTAL GENERATION) 34% 36% Figure: 3.10 Scale at A4: N/A Drawn DW Checked PK Approved KK Date 23/05/07 Revised 2 Date 30/08/2007

20 11% 14% 66% 51% 23% 71% Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH11.1 SHERFORD ROUTE SPLIT (FULLY SIGNALISED MAIN STREET - PM TOTAL GENERATION 29% 35% Figure: 3.11 Scale at A4: N/A Drawn DW Checked PK Approved KK Date 23/05/07 Revised 2 Date 30/08/2007

21 Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH SHERFORD ROUTE FLOWS (FULLY SIGNALISED MAIN STREET - AM TOTAL GENERATION Figure: 3.12 Scale at A4: N/A Drawn DW Checked PK Approved KK Date 23/05/ Revised 2 Date 30/08/2007

22 Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Plots.FH SHERFORD ROUTE FLOWS (FULLY SIGNALISED MAIN STREET - PM TOTAL GENERATION Figure: 3.13 Scale at A4: N/A Drawn DW Checked PK Approved KK Date 23/05/ Revised 2 Date 30/08/2007

23 Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Internal Network AM 2016.FH Northern Distributor West Central Junction Southern Distributor West SHERFORD AM 2016 INTERNAL NETWORK (SATURN) Southern Distributor East Key Movement Location Northern Distributor East New Plymouth Bound Slip Figure: 3.14 Scale at A3: N/A Drawn DW Checked KK Approved GB Date 30/05/2007 Revised 1 Date 07/09/2007

24 Drawing Ref:K:\D Sherford\Drawings\Freehand\Saturn Internal Network AM 2016.FH Northern Distributor West Central Junction Southern Distributor West SHERFORD PM 2016 INTERNAL NETWORK (SATURN) Southern Distributor East Key Movement Location Northern Distributor East New Plymouth Bound Slip Figure: 3.15 Scale at A3: N/A Drawn DW Checked KK Approved GB Date 30/05/2007 Revised 1 Date 07/09/2007

25 SHERFORD MAIN STREET STRATEGY 4. MICRO-SIMULATION 4.1 RATIONALE Micro-simulation is being considered as a tool which can be employed to show how bus priority through the Main Street is being facilitated. This has been recognised by the Local Highway Authorities to be crucial in helping to support the predicted modal shares presented in the TA The benefits of micro-simulation over the submitted SATURN model will be in its ability to define and show how bus priority through the Main Street would operate, in real-time SATURN, as a deterministic model, where an output is precisely determined by an input, has difficulty encompassing descriptions of detailed features such as Urban Traffic Controls, bus priority systems and pedestrian controlled crossings. Microsimulation can incorporate all of these features, and produce a range of results that reflect the likely variability in conditions experienced by real transport users. 4.2 MODELLING AND SCOPE While there are a number of micro-simulation models available including PARAMICS, VISSIM is generally recognised as the preferred micro simulation model when dealing with urban networks (TfL, 2003). This is because it is generally more suited for detailed driving conditions, as it is able to model features such as acceleration and deceleration speeds, pedestrian crossings and bus gates at a greater level of accuracy than other available software packages Producing a workable micro-simulation model of the Main Street will be controlled by the ability of the project team to get absolute agreement on the scope and limitations of the model but also on the traffic flow scenario presented in the TA A scoping document is being prepared on the specifications for a VISSIM model covering the whole of Sherford (WS). Given the current timescales, the MWG suggested that the formulation of the strategy could be progressed initially by considering a micro-simulation model for the Main Street only, to be informed by the SATURN assignment set out in this strategy document In doing so, a VISSIM model of the Main Street Only (MSO) would allow for the determination of the Sherford application to be made from the perspective of ensuring that sufficient bus priority had been provided In order to progress the application, the MSO model would be based around a cordon of flows originating from the preferred SATURN assignment which has been used to inform the chosen strategy It was recognised however, by all involved, that a developing a WS model could subsequently help to ensure that the effects of bus priority on the assignment of traffic could also be taken into account. It was also agreed that such a model would then remain an active tool and include details of other areas of Sherford as these come on-line. 30th August

26 SHERFORD MAIN STREET STRATEGY 5. SUMMARY 5.1 This Technical Note has established that the internal distribution of traffic within Sherford can be managed to a certain extent through the implementation of intervention measures. In doing so, the relationship between the Main Street and the Northern/Southern Avenues can be influenced with the aim of achieving an appropriate balance of flows, thereby contributing to the promotion of the High Street as a vibrant place, which is not unduly dominated by traffic. 5.2 The baseline of vibrancy, from a traffic volumes perspective, was established by means of the assessment of two case study towns, namely Marlborough and Honiton. This analysis has highlighted 12-hour two-way flows in the order of 10,000-15,000 vehicles to be appropriate levels. In comparison, the analysis for Sherford suggests a throughput of between 8,000-11, The ability to shape the environment and to control the throughput of traffic along the High Street is possible. The modelling completed for the TA assumed relative difference in road hierarchy that, whilst suitable in urban design terms, may not be appropriate from a highway capacity perspective. Alternative scenarios were therefore devised, whereby no perceived speed advantage was given to the Main Street in relation to the Northern and Southern Avenues. 5.4 The SATURN model was developed in order to inform the assignment of traffic and ultimately the detailed testing of the Main Street junctions. Equally, the results of these tests can be fed back into SATURN to determine the impact on routing, particularly in terms of shaping the overall strategy and to provide a marker for change as Sherford progresses. The purpose of this scenario would be to inform the development of a micro-simulation model which would indicate how bus priority is facilitated through the Main Street. 5.5 Finally, the area of micro-simulation is briefly discussed in advance of a scoping note of the exact specification of a VISSIM model. In the context of the current timescales, it is anticipated that a two-stage process will be implemented. Stage 1, which will be based on a Main Street Only (MSO) model and will use the assignment information from SATURN, will be concerned with demonstrating how sufficient bus priority will be implemented. 5.6 Consultation with the Local Highway Authorities suggested that this strategy could offer elements that could be benchmarked against when considering the expansion of Sherford, thereby helping to guide the build-out from an active traffic management perspective. 30th August

27 SCOTT WILSON SHERFORD, PLYMOUTH TECHNICAL NOTE 9 (v2): THROUGH TRAFFIC MATRIX DEVELOPMENT Ref: D CA18 August 2007

28 SHERFORD, PLYMOUTH Technical Note 9 (v2): Through Traffic Matrix Development Collated and edited by: Reviewed by: Approved by: Paul Kelly Transport Consultant Kevin Kay Senior Transport Consultant Sandy Burrell Technical Director Scott Wilson Scott House Basing View Basingstoke RG21 4JG Tel: +44 (0) Fax: +44 (0) Disclaimer This document has been prepared in accordance with the scope of Scott Wilson's appointment with its client and is subject to the terms of that appointment. It is addressed to and for the sole use and reliance of Scott Wilson's client. Scott Wilson accepts no liability for any use of this document other than by its client and only for the purposes, stated in the document, for which it was prepared and provided. No person other than the client may copy (in whole or in part) use or rely on the contents of this document, without the prior written permission of the Company Secretary of Scott Wilson Ltd. Any advice, opinions, or recommendations within this document should be read and relied upon only in the context of the document as a whole. The contents of this document are not to be construed as providing legal, business or tax advice or opinion. Scott Wilson Group plc 2006

29 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT 1. INTRODUCTION In 2006, Scott Wilson (SW) prepared a Transport Assessment (TA) in support of a new sustainable development at Sherford, located to the east of the City of Plymouth, in Devon Following a meeting held with Plymouth City Council (PCC) on 23 rd March 2007, and corresponding letter from PCC dated the 11 th June 2007, additional information was requested to support the through traffic methodology presented in the TA This note will detail the methodology adopted in the TA, to present a detailed account of the impact of modelling on how through traffic and how the Origin- Destination data collected fed into this process. 20 th August

30 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT 2. DATA COLLECTION Origin-Destination data was collected by Count-on-Us on the 3rd November 2005 for a 12 hour period ( ) Two cordon sites, one northern and one southern was provided initially, as illustrated by FIGURE 2.1. The south cordon consists of output and input flows at locations 1-16, while the northern cordon takes account of the traffic outputs and inputs at locations 13 to Given the requirements for determining cross-sherford movement, the enumeration company also supplied an outer cordon matrix. The area covered by the outer cordon matrix is shown in FIGURE 2.1, and the resultant matched counts for the AM and PM peaks for the outer cordon are illustrated below in TABLE 2.1 and TABLE 2.2. Table 2.1: AM Observed Trip Matrix for Outer Cordon Plympton A379 A379 A379 Brixton Local A38 A38 Hill West South East Road East East West Zone ID O2 O10 O9 O8 O12 O18 O21 O20 Plympton Hill I A379 West I A379 South I A379 East I Brixton Road I Local East I A38 East I A38 West I Total Total Table 2.2: PM Observed Trip Matrix for Outer Cordon Plympton A379 A379 A379 Brixton Local A38 A38 Hill West South East Road East East West Zone ID O2 O10 O9 O8 O12 O18 O21 O20 Plympton Hill I A379 West I A379 South I A379 East I Brixton Road I Local East I A38 East I A38 West I Total Total 20 th August

31 Drawing Ref:K:\D Sherford\Drawings\Freehand\Origin Destination Matrix Cordons.FH A379 Elburton Road A38 SHERFORD ORIGIN DESTINATION MATRIX CORDONS Sherford Road Vinery Lane Brixton Road 3 4 A Deep Lane Figure: 2.1 Scale at A4: N/A Drawn GH Checked KK Approved GB Date 07/09/ Ridgeway Key: Revised 2 Date 17/04/07 Sandy Road Northern Cordon Southern Cordon Combined Cordon

32 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT 3. MATRIX REFINEMENT In order to establish a comprehensive matrix of through traffic for Sherford, it was necessary to address and consider a range of uncertainties: the volume of traffic entering or leaving the cordon to the north of Deep Lane; and the number of vehicles whose journey originates from, or ends at the Elburton residential area, which is located within the cordon area 3.2 DEEP LANE NORTH To ascertain the contribution to the through matrix of vehicles leaving or entering the cordon north of Deep Lane, intermediate manual classified counts were used to provide a reference point to assess the level of traffic that remained unmatched These manual classified counts were conducted at the same time as the origin destination survey and were also collected over the course of the day for all of the sites shown in FIGURE 2.1. Table 3.1 shows the comparison between the O-D and MCC surveys. Table 3.1: O-D and MCC Survey Comparison Site ID Site Description AM Peak PM Peak Survey MCCs Ratio Survey MCCs Ratio 1 Plympton Hill (In) % % 2 Plympton Hill (Out) % % 5 A379 West (In) % % 6 A379 South/Springfield Road (In) % % 7 A379 East (In) % 0 1 0% 8 A379 East (Out) % 0 4 0% 9 A379 South (Out) % % 11 Brixton Road (In) % % 12 Brixton Road (Out) % % 17 Local East (In) % 0 6 0% 18 Local East (Out) % % 19 A38 East (In) % % 20 A38 West (Out) % % 21 A38 East (Out) % % 22 A38 West (In) % % The Table above indicates that a number of trips start or end within the cordon. For example, a number of trips will be associated with movements from the residential areas of Elburton and an allowance for this has been made in the methodology, as described in PARAGRAPH The opportunity for abstraction, however, is very limited when considering the northern cordon alone, given the absence of obvious attractors/producers. The sample rates achieved for the southbound cordon entries are thus more representative of the integrity of the O-D survey to adequateky the patterns of movements within the area as a whole. 20 th August

33 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 3.2: Northern Cordoned Matrix Site ID O14 O16 O18 O20 O21 Total MCCs Ratio I % I % I % I % I % Tot MCCs Ratio 92% 76% 14% 95% 89% Site represent movements which are only susceptible to recording error. The level of matching is therefore assumed to be very good with 89% to 95%. It is evident from FIGURE 2.1 that areas to the North of Deep Lane will account for the difference occurring for the other movements in the matrix. An estimation can therefore be made as to the quantum of traffic going across the Deep Lane junction so that: DL S/B (I23) = Sum(O14,O16,O18) - Sum(I19, I22) DL N/B (O24) = Sum(I13,I15,I17) - Sum(O20, O21) The resultant number of vehicles travelling across the Deep Lane junction is therefore assumed to be 108/127 in the AM and 130/97 in the PM peak for the southbound and northbound movements respectively. The zones thereby created have been termed I23 and O24, as shown in TABLE 3.3 and TABLE 3.4 below. 20 th August

34 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 3.3: AM Trip Matrix for Outer Cordon Plympton Hill A379 West A379 South A379 East Brixton Road Local East A38 East A38 West Zone ID O2 O10 O9 O8 O12 O18 O21 O20 O24 DL North Total MCCs Diff Plympton Hill I A379 West I A379 South I A379 East I Brixton Road I Local East I A38 East I A38 West I DL North I Total MCCs Diff th August

35 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 3.4 PM Trip Matrix for Outer Cordon Plympton Hill A379 West A379 South A379 East Brixton Road Local East A38 East A38 West Zone ID O2 O10 O9 O8 O12 O18 O21 O20 O24 DL North Total MCCs Diff Plympton Hill I A379 West I A379 South I A379 East I Brixton Road I Local East I A38 East I A38 West I DL North I Total MCCs Diff th August

36 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT The absolute difference between the row/column totals and the observed count for each survey location, shown in the above tables, can be taken to be representative of the traffic which had not been picked up by the survey. A proportion of these will be the trips associated with the Deep Lane zones, as discussed, with the remainder being associated with the residential area of Elburton Individual matrix movements associated with I23 and O24 were calculated using the following operations, the results of which are shown in TABLE 3.5 and TABLE 3.6 below. Unlikely two-way movements set to zero based on likelihood of undertaking particular routings (I23-O2, I1-O24) Unlikely pairs set to zero based on the specification of the surveyed movements (I23-021, I23-O20, I23-O24, I19-O24, I22-O24) For zones I11 and O12, the amount of trips associated with Elburton is likely to be insignificant, implying that the difference is associated with the Deep Lane zone. As a result, 31/34 inbound and 31/22 outbound trips have been assigned to these O-D pairs, allowing for a recording error of 15%, for robustness. The remaining cells were infilled with values calculated from the proportional split of the row and column totals (excluding I11/O12) based on the weighting of corresponding MCC totals The outcome of the above calculations means that the row and column totals for this element now match the totals in TABLE 3.3 and TABLE The Elburton residential, which is internal to the outer cordon, was added to the matrix and the appropriate cells were infilled by assuming that 85% of the differences between the corresponding sub-totals and the MCCs observed values (i.e. a recording error of 15%) were accounted for by trips to/from this zone and hence those trips which was not picked up by the O-D survey explicitly. TABLE 3.5 and TABLE 3.6 illustrate the results of this process. 20 th August

37 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 3.5: AM Trip Matrix for Outer Cordon Plympton Hill A379 West A379 South A379 East Brixton Road Local East A38 East A38 West DL North Zone ID O2 O10 O9 O8 O12 O18 O21 O20 O24 Elburton Plympton Hill I A379 West I A379 South I A379 East I Brixton Road I Local East I A38 East I A38 West I DL North I Sub-Total Elburton I New Total MCCs Sub- Total O26 New Total MCCs 20 th August

38 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 3.6 PM Trip Matrix for Outer Cordon Plympton Hill A379 West A379 South A379 East Brixton Road Local East A38 East A38 West DL North Zone ID O2 O10 O9 O8 O12 O18 O21 O20 O24 Elburton Plympton Hill I A379 West I A379 South I A379 East I Brixton Road I Local East I A38 East I A38 West I DL North I Sub-Total Elburton I New Total MCCs Sub- Total O26 New Total MCCs 20 th August

39 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT By adopting this approach, there are still slight variations between the surveyed data and observed counts. It is the aim of the furnessing therefore to retain the internal structure of the prior matrix in seeking to match the new total to the MCC value, for each row and column. 3.3 FURNESSING In order to get a pattern of movements which is representative of the observed conditions, the matrix was furnessed using the count totals The furnessing process seeks to match the column and row totals through a series of iterations, with minimum error. The cordon matrix converged around the 16 th iteration (6% error), so the 20 th iteration of the matrix was used (also 6%) The resultant modified furnessed through matrices for the AM and PM peaks are illustrated below in TABLE 3.1 and TABLE th August

40 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 3.7: Furnessed AM Trip Matrix for Outer Cordon Plympton Hill A379 West A379 South A379 East Brixton Road Local East A38 East A38 West DL North Elburton Zone ID O2 O10 O9 O8 O12 O18 O21 O20 O24 O26 Plympton Hill I A379 West I A379 South I A379 East I Brixton Road I Local East I A38 East I A38 West I DL North I Elburton I Total Total 20 th August

41 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 3.8 Furnessed PM Trip Matrix for Outer Cordon Plympton Hill A379 West A379 South A379 East Brixton Road Local East A38 East A38 West DL North Elburton Zone ID O2 O10 O9 O8 O12 O18 O21 O20 O24 O26 Plympton Hill I A379 West I A379 South I A379 East I Brixton Road I Local East I A38 East I A38 West I DL North I Elburton I Total Total 20 th August

42 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT 4. EXTENDING THE THROUGH MATRIX In order to accurately reflect the traffic flows across the immediate network, additional information not directly picked up by the scope of the O-D survey was required. The purpose of the additional analysis is to convert and add to the matrices presented in TABLE 3.7 and TABLE 3.8 so that a new matrix can be created for input into the SATURN model which was developed specifically for modelling the internal Sherford network The zoning system in the SATURN model is composed of the zones shown in TABLE 4.1 and also geographically in FIGURE 4.2. For comparison, the Zone ID referenced in the O-D survey exercise carried out has also been included where appropriate. Table 4.1 SATURN Zone Connectors SATURN_ID Zone Decription O-D 1004 Plympton Hill I1/O A379 West I5/O A379 East through I7/O Brixton Road I11/O Local East I17/O A38 East I19/O A38 West I22/O North of Deep Lane I23/O Elburton I25/ Haye Road n/a 1013 Stanb'gh X S Through 1014 Elburton S Through I6/O Deep Lane E Through n/a The O-D survey only looked at movements entering and leaving the cordon at Elburton Roundabout, shown in FIGURE 2.1. Additional count information was used to extend the matrix by including cells pertaining to the Elburton and Stanborough Cross junctions. These additional traffic counts are shown in TABLE 4.22 and are intended to supplement. Table 4.2: Additional Traffic Counts Road Direction Count Source and Date A379 Traffic travelling East and West which does not Plymouth City Council, enter surveyed cordon October 2003 A379 Stanborough Cross coming out of, or going into Plymouth City Council, Sherford October These counts were factored to the 2005 situation using the factors shown in TABLE 4.3. Further detail regarding the development of background growth rates is presented in the TA. 1 Split between Springfield Road and Stanborough Road according to TABLE th August

43 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 4.3: Growth Rates for the 2005 Baseline and 2016 Scenarios From To AM PM Weekday The cell locations that have been appended to the matrix relate to the Stanborough Cross/Elburton junctions. A diagram of movements across the complex, as illustrated in FIGURE 4.1, was developed using the existing turn information to extrapolate the information in a format suitable for inputting into the matrix. Figure 4.1 Stanborough Cross/Elburton Junction Traffic Movement Diagram A D B STX ERB E C F G Each set of movements was broken down into a from-via-to format, the basis for which was the relative turning proportions at each locations, as shown in TABLE 4.4 below. 20 th August

44 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 4.4 Movement disaggregation based on factored 2003 counts Movements AM Peak PM Peak A B A F A C D A C E A C G B A B F B C D B C E B C G D E 8 3 D G D C A D C B D C F E D 9 10 E G E C A E C B E C F F B G C B F A G C A G D F C D G E F C E F C G G C F The resultant flows for which were combined in a matrix format. This is shown in TABLE th August

45 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 4.5 Stanborough Cross/Elburton Roundabout Matrix Format Haye Road A379 West Sherford A379 East Stanborough Cross South Elburton South AM PM AM PM AM PM AM PM AM PM AM PM Haye Road A379 West Sherford A379 East Stanborough Cross South Elburton South Other non Sherford related movements at Deep Lane, which the O-D survey did not cover, have also been added to the overall matrix. However, no through traffic was specified for east and west movements along the main A38 carriageway which runs underneath the Deep Lane junction Finally, the matrices were factored to reflect the 2016 situation using the rates shown in TABLE 4.6. Further detail regarding the growth rates used to factor the Sherford counts is presented in the TA. Table 4.6: Growth Rates for the 2005 Baseline and 2016 Scenarios From To AM PM Weekday The exception to this is the traffic that was assigned to the Elburton residential area as it is assumed any growth in the area, in terms of how it is derived, is associated with the creation of the Sherford development. The final through traffic matrix for the AM and PM peak is illustrated in TABLE 4.7 and TABLE 4.8. In the TA, this was shown as Table 3.8 and Table 3.9, although the title should have read TABLE 4.9 and TABLE 4.10 shows the equivalent tables with the corresponding SATURN nomenclature. 20 th August

46 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 4.7: SATURN through traffic matrix for the AM peak (Do Minimum 2016) SATURN ID Total Total th August

47 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 4.8: SATURN through traffic matrix for the PM peak (Do Minimum 2016) SATURN ID Total Total th August

48 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 4.9: Through traffic matrix for the AM peak 2016 (TA) Zone Descriptors/Saturn ID A38 E Deep Lane A38 W Plympton Hill Haye Road A379 W Local East Brixton Road Elburton A379 E South DLN E A38 E Deep Lane A38 W Plympton Hill Haye Road A379 W Local East Brixton Road Elburton A379 E South DLN E th August

49 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT Table 4.10: Through traffic matrix for the PM peak 2016 (TA) Zone Descriptors/Saturn ID A38 E Deep Lane A38 W Plympton Hill Haye Road A379 W Local East Brixton Road Elburton A379 E South DLN E A38 E Deep Lane A38 W Plympton Hill Haye Road A379 W Local East Brixton Road Elburton A379 E South DLN E th August

50 North of Deep Lane 1002 Plympton Hill 1004 DLN East 1015 A38 East 1001 A38 West 1003 A38 A38 Deep Lane Vinery Lane Local East 1009 Drawing Ref:K:\D Sherford\Drawings\Freehand\Origin Destination Matrix Cordons from Network.FH11.1 A379 West 1006 A379 Elburton Road Stanborough Cross South 1013 Elburton South 1014 Haye Road 1005 Elburton 1011 Sherford Road A379 East 1012 SHERFORD ORIGIN DESTINATION SATURN ID S Brixton Road 1010 Figure: 4.2 Scale at A4: N/A Drawn GH Checked PK Approved KK Date 16/08/07 Revised 1 Date 16/08/07

51 SHERFORD, PLYMOUTH THROUGH TRAFFIC MATRIX DEVELOPMENT 5. SUMMARY This Technical Note has been prepared to supplement the Transport Assessment that was submitted in November 2006, in support of the proposed Sherford development The note has presented the methodology related to the establishment of the matrices and then how a strategy for assignment was developed to take account of the impact of Sherford on the eventual assignment of through traffic Following consultation with the Highways Agency, Devon County Council and Plymouth City Council, this note was revised to clarify and set out the processes involved in the formulation of the matrices, shown in TABLE 3.8 and TABLE 3.9 of the Transport Assessment A number of refinements were included in the consideration of through traffic. These relate to the relationship between the various cordons and how the matrices were factored to match observed turning flows. The main elements of this are: Modification of the original trip matrix to consider and account for any unknown and unmatched flows within the Outer Cordon; Matrix furnessing to ensure the surveyed sample turning movements were balanced against the surveyed total flows at the cordon boundary to eliminate sampling error; and Extending the matrix using existing traffic counts to accurately reflect the external connectors modelled in the SATURN model of Sherford Finally, the matrices created were assigned in the SATURN model as part of a three-stacked set, which were divided between internal, external and Sherfordbased traffic. 20 th August

52 SCOTT WILSON SHERFORD, PLYMOUTH TECHNICAL NOTE 10(v2): MAIN STREET BUS PRIORITY OPERATION Ref: D CA23 August 2007

53 SHERFORD, PLYMOUTH Technical Note 10 (v2): Main Street Bus Priority Operation Collated and edited by: Reviewed by: Approved by: Tareq Englefield Transport Planner Kevin Kay Senior Transport Planner Sandy Burrell Technical Director Scott Wilson Scott House Basing View Basingstoke RG21 4JG Tel: +44 (0) Fax: +44 (0) Disclaimer This document has been prepared in accordance with the scope of Scott Wilson's appointment with its client and is subject to the terms of that appointment. It is addressed to and for the sole use and reliance of Scott Wilson's client. Scott Wilson accepts no liability for any use of this document other than by its client and only for the purposes, stated in the document, for which it was prepared and provided. No person other than the client may copy (in whole or in part) use or rely on the contents of this document, without the prior written permission of the Company Secretary of Scott Wilson Ltd. Any advice, opinions, or recommendations within this document should be read and relied upon only in the context of the document as a whole. The contents of this document are not to be construed as providing legal, business or tax advice or opinion. Scott Wilson Group plc 2006

54 SHERFORD, PLYMOUTH MAIN STREET BUS PRIORITY OPERATION TABLE OF CONTENTS 1. INTRODUCTION BUS PRIORITY OVERVIEW SHERFORD HIGHWAY MANAGEMENT MAIN STREET SUMMARY th August 2007 iii

55 SHERFORD, PLYMOUTH MAIN STREET BUS PRIORITY OPERATION 1. INTRODUCTION 1.1 In 2006, Scott Wilson (SW) prepared a Transport Assessment (TA) in support of a planning application for the redevelopment of a sustainable new community at Sherford, located to the east of the City of Plymouth, in Devon. 1.2 This technical note aims to expand on the work undertaken in the TA, by considering the operation of bus priority measures that will be implemented for the High Quality Public Transport (HQPT) scheme. This serves to supplement the analysis undertaken at the Stanborough Cross/Haye Road junction complex and to demonstrate that bus priority can be delivered along the Main Street alignment. 1.3 The HQPT is a bus based system that is designed to provide high quality, high capacity vehicles, run at short intervals with supporting infrastructure and technology that will help to ensure its reliability. 1.4 Bus priority can be delivered in a number of forms but generally fall into two categories; physical infrastructure priority (i.e. bus lanes) and selective vehicle detection (SVD) (i.e. technology assisted priority at junctions). In addition to the various priorities available, it is anticipated that the general management of traffic will provide a fundamental base onto which an effective bus priority scheme can be built. 1.5 This note will prove a useful benchmark against which the micro-simulation model of the Main Street will be built. This should allow the options described in this report to be tested in a real-time environment. 1.6 HQPT is a fundamental element of the sustainable transport strategy for Sherford, which Red Tree are committed to support through the provision of the necessary infrastructure along the Main Street. It is recognised, however, that a number of stakeholders are involved in the process and that an Eastern Infrastructure Study has been commissioned by Plymouth City Council, the purpose of which is to provide an integrated approach to HQPT delivery along the whole A379 corridor and to identify measures to complement the range of measures being provided along the Main Street. 1.7 The bus priority provision and operation at Stanborough Cross / Haye Road is covered by the technical note Stanborough Cross Operational Review, and it is important that the proposals at this location are considered alongside the operation of the Main Street. 20th August

56 SHERFORD, PLYMOUTH MAIN STREET BUS PRIORITY OPERATION 2. BUS PRIORITY OVERVIEW 2.1 Where a route improvement strategy can be implemented, as proposed by the Sherford HQPT principles, both categories of priority can be delivered, physical priorities to provide the unrestricted passage of buses through the development, and SVD to assist the buses through the signalised junctions. 2.2 SVD Bus Priority enables the signal timings to be automatically adjusted to benefit the buses, either by extending a current green signal (a green extension Figure 2.1) or by returning to the green signal required by a bus in the shortest possible time (a green recall Figure 2.2). Figure 2.1 SVD Bus Priority Extension Figure 2.2 SVD Bus Priority Recall 20th August

57 SHERFORD, PLYMOUTH MAIN STREET BUS PRIORITY OPERATION 2.3 Selective Vehicle Detection (SVD) can further help to improve the regularity of buses by providing priority only to those buses that are behind schedule or, by increasing the priority given to late buses above buses that are on time or running early. 2.4 If desired, higher levels of priority can be provided than the active priority facility, described above, by overriding the standard control method and utilising a hurry call and/or green waves, traditionally reserved for emergency vehicles. 2.5 Co-ordination and offsets between signalised junctions will need to be given consideration to ensure that the impact of SVD does not result in net disbenefits for buses. 2.6 Spare capacity will be a determining factor in the level of priority available to buses. SVD Bus Priority uses the degree of saturation (DOS) of opposing approaches to determine whether extensions or recalls are permitted. In the case of Sherford Main Street it will be the side roads that will be constrained, and thus parameters can be utilised that highly favour buses. 2.7 The number of buses per hour will impact on the effectiveness of the priority implemented. With Sherford, the majority of buses will not run in conflicting stages so the bus flow would be considered relatively low, for example compared to Central London, and therefore highly suitable for SVD Bus Priority. 20th August

58 SHERFORD, PLYMOUTH MAIN STREET BUS PRIORITY OPERATION 3. SHERFORD HIGHWAY MANAGEMENT Signal Control 3.1 The SCOOT (Spilt, Cycle and Offset Optimisation Technique) signal control system would be a viable option for the operation of signalised junctions along the Main Street. It is an adaptive system that responds automatically to fluctuations in traffic flow through the use of on-street detectors embedded in the road. 3.2 SCOOT would allow effective management of the corridor by giving a wide range of control features as well as facilitating operational visibility of the junctions. The successful set up of the system could enable the corridor to self manage, as well as react to incidents. 3.3 It should be noted that SCOOT is now available to run using a desktop PC reducing many of the set up and running costs that have in the past reduced the attractiveness of the system. 3.4 As SCOOT controls junctions in Regions, a number of closely associated junctions, the following operational overview will discuss bus priority on a potential Region by Region basis. 3.5 SCOOT Gating could be utilised to constrain the input of traffic from the side roads, in a region, should a higher degree of saturation or queuing be detected on the Main Street. 3.6 The SCOOT UTMC (Urban Traffic Management & Control) facility provides more operational control over gating and could be used to implement alternative plans, activate a green waves as well as adjust general operational parameters. Further to this, strategies can be developed to control real time information, improve safety and monitor/control environmental issues. 3.7 Green Waves are a tool that can be utilised to run a wave of green lights allowing vehicles to clear a number of junctions. Essentially they operate by instigating a hurry call at each junction on any specified route. This function is normally reserved for emergency vehicles although its use has been recently proven by Transport for London. 3.8 SCOOT is also able to monitor and record observed traffic information, which is automatically compiled into the systems database (ASTRID). 3.9 The set up of these facilities is relatively straight forward, once the hardware is in place it is a case of implementing and adjusting the various strategies via the SCOOT computer. SCOOT s flexibility would allow for the continual development of strategies over the construction phases and well into the future. Infrastructure 3.10 Bus lanes will assist the free flow of buses whilst providing a visible benefit for buses Bus Gates will enable buses to gain advantage over the private motor vehicle, again in a visible manner. 20th August

59 SHERFORD, PLYMOUTH MAIN STREET BUS PRIORITY OPERATION Parking 3.12 Parking on-street in dedicated bays, as provided along the High Street and along a number of sections of the Main Street, will assist the free flow of all vehicles, especially public service vehicles which are generally wider than the private motor vehicle Parking controls will further assist the free flow of vehicles and should be considered for a number of time periods. Buses 3.14 The buses utilised at Sherford should by their very nature assist in providing a reliable service along the main street. The number of doors will be an important factor in decreasing the journey time due to reduced dwell times at bus stops. This should also lead to better forecasts of dwell times, which could be utilised for future advancements in SVD bus priority for route management The use of smart cards will further assist in decreasing dwell times by reducing the need for passengers to engage with the driver Smart Cards represent one of the latest developments in public transport travel, especially on buses, although they have been in operation for some time in major cities such as London, in the form of the Oyster card. The cards can either be bought in advance for a specific journey or for a period of time, eg. a month or a year, with journeys pre-paid for. For example, travellers can either pay a sum of money which is incrementally used up with each journey, or it may be possible to pay a rate for a months worth of travel on a given service. In Scotland Smart Cards for bus travel, were issued to all residents over 60 and those with mobility impairments, qualifying for free travel anywhere in Scotland, at any time, earlier this year The Smart Cards mean that there is no requirement for payment, the passenger simply boards the vehicle, swipes or touches the card against a sensor, and finds a seat. This should facilitate easier passage onto and off of buses, as well as a more straight forward payment mechanism In Plymouth, Smart Cards are being rolled out, and operators such as the Plymouth City Bus have introduced the new ticketing technology on the Wayfarer routes in the form of the 'PLYM' Smart Card, which is expected to become the preferred Smart Card for the area. It is anticipated that as the preferred Smart Card system is established, it is implemented as part of the Sherford HQPT. 20th August

60 SHERFORD, PLYMOUTH MAIN STREET BUS PRIORITY OPERATION 4. MAIN STREET 4.1 The design of the Main Street is instrumental to the success of HQPT and the integration of various traffic management techniques and bus priorities will enable Sherford to provide a reliable service for residents, employees and visitors. 4.2 The management and priorities afforded to the various Regions along the Main Street are described in the following section, their location and further detail is provided by FIGURE 4.1 North Region 4.3 Northern Avenue Distributor East & Southern Avenue Distributor East: SVD with DOS below 90%, this site is likely to be very conducive to higher levels of priority. Hurry Call potentially good site due to all approaches having two lanes on their approach giving good availability for stacking of vehicles. SCOOT Control The use of the split weighting control could be utilised to ensure that the Main Street runs at a maximum of 90% or lower, ensuring the free flow of traffic on bus routes. 4.4 This Region is likely to be conducive to high levels of SVD bus priority, offering good potential for traffic management. Due to suitability of the junctions to provide hurry calls, it is probable that green waves will prove successful. Central Region 4.5 High Street East Bus Lane Crossover & Central Junction: These junctions are provided essentially as a means of facilitating buses to move into the segregated bus lanes running centrally through the High Street. As such, the operation of the junction will by definition prioritise buses as they are detected and are facilitated into the central running carriageway. SVD - with DOS below 90%, these sites are likely to be very conducive to higher levels of priority. Hurry Call potentially good sites due to the segregation of buses which will enable their free flow allowing the junctions to return to normal operation in a timely, reliable manner. SCOOT Control The use of the split weighting control could be utilised to ensure that the Main Street runs at a maximum of 90% or lower, insuring the free flow of traffic on bus routes. 4.6 Northern Avenue Distributor West: SVD - with DOS below 90%, this site is likely to be very conducive to higher levels of priority. 20th August

61 SHERFORD, PLYMOUTH MAIN STREET BUS PRIORITY OPERATION Hurry Call as part of the Central Region a Hurry Call facility at this location may assist the progression of buses. SCOOT Control The split weighting controller should be utilised to ensure that the Main Street runs at a maximum of 90% or lower, ensuring free flow of traffic on bus routes. 4.7 This Region will provide advantages for buses that are highly visible to all road users through the use of highway infrastructure and also is likely to be conducive to high levels of SVD bus priority. Careful implementation of green waves will need to be utilised due to the provision of bus stops in relation to adjacent junctions, but general traffic management will assist. School Loop Region 4.8 School Loop Bus Gate North & South: These junctions are provided to enable buses to enter into the segregated bus lanes running across the School Loop Junction Complex. SVD - with DOS below 70%, these sites should be able to offer extremely high levels of priority. Hurry Call potentially good sites as the segregation of buses which will enable their free flow, allowing the junctions to return to normal operation in a timely, reliable manner. SCOOT Control As the junctions only enable the movement of buses into the segregated area, the control of the junctions is biased towards public transport. 4.9 The highway infrastructure found in the Region will provide further highly visible advantages afforded to buses. Green waves are unlikely to give further benefits due to the provision of bus stops and therefore relatively variable dwell times. 20th August

62 SHERFORD, PLYMOUTH MAIN STREET BUS PRIORITY OPERATION 5. SUMMARY 5.1 This note demonstrates that a number of bus priority control methods and strategies are proposed for Sherford. These are aimed at reducing the time taken by buses to travel along the Main Street and to make the benefit being afforded to public transport visible to vehicular users, thereby helping to promote the efficiency and reliability of HQPT to anyone who has a requirement to travel through the development. 5.2 This document has then detailed the suggested priority and control measures which could be delivered for each specified section of the Main Street on the basis of their individual characteristics and their suitability for particular bus priority interventions. 5.3 A variety of management strategies have been highlighted, the implementation of which will help to ensure that the flow of traffic along the Main Street can be managed from the perspective of providing signal setting variability which favour the public transport over the private car, thus helping to support the infrastructure commitments made by Sherford in the delivery of the HQPT by the stakeholders. 20th August

63 Key Planning Application Boundary Bus Stop Ridgeway Bus Lane SVD Enabled Signalised Junctions Park and Ride Deep Lane Junction with Slip Roads Sherford Proposed Park and Ride Northern Distributor East Bus Lane Crossover Central High Street Junction North Northern Distributor West Stanborough Cross / Haye Road Central Bus Gate North Drawing Ref:K:\D Sherford\Drawings\Freehand\Proposed Extent of Vissim Model.FH11.1 Southern Distributor East Bus Gate South School Loop Haye Road School Loop Proposed Stanborough Cross Layout Crown Copyright. All rights reserved. License number SHERFORD MAIN STREET BUS PRIORITY Figure : 4.1 Scale at A3: N/A Drawn DW Checked TE Approved GB Date 04/07/07 Revised 2 Date 30/08/07

64 SCOTT WILSON SHERFORD, PLYMOUTH TECHNICAL NOTE 11 (v2): STANBOROUGH CROSS OPERATIONAL REVIEW Ref: D CA12 October 2007

65 SHERFORD, PLYMOUTH TECHNICAL NOTE 11 (v2): STANBOROUGH CROSS OPERATIONAL REVIEW Collated and edited by: Reviewed by: Approved by: Tareq Englefield Transport Planner Kevin Kay Senior Transport Planner Sandy Burrell Technical Director Scott Wilson Scott House Basing View Basingstoke RG21 4JG Tel: +44 (0) Fax: +44 (0) Disclaimer This document has been prepared in accordance with the scope of Scott Wilson's appointment with its client and is subject to the terms of that appointment. It is addressed to and for the sole use and reliance of Scott Wilson's client. Scott Wilson accepts no liability for any use of this document other than by its client and only for the purposes, stated in the document, for which it was prepared and provided. No person other than the client may copy (in whole or in part) use or rely on the contents of this document, without the prior written permission of the Company Secretary of Scott Wilson Ltd. Any advice, opinions, or recommendations within this document should be read and relied upon only in the context of the document as a whole. The contents of this document are not to be construed as providing legal, business or tax advice or opinion. Scott Wilson Group plc 2006

66 SHERFORD, PLYMOUTH TECHNICAL NOTE 11 (v2) STANBOROUGH CROSS OPERATIONAL REVIEW TABLE OF CONTENTS 1. INTRODUCTION STANBOROUGH CROSS TRANSYT STANBOROUGH CROSS BUS PRIORITY CONCLUSION... 6 October 2007 iii

67 SHERFORD, PLYMOUTH TECHNICAL NOTE 11 (v2) STANBOROUGH CROSS OPERATIONAL REVIEW 1. INTRODUCTION 1.1 In 2006, Scott Wilson (SW) prepared a Transport Assessment (TA) in support of a planning application for the redevelopment of a sustainable new community at Sherford, located to the east of the City of Plymouth, in Devon. 1.2 This technical note aims to expand on the work undertaken in the TA, by considering the operation of the Stanborough Cross junction complex and bus the priority measures that will be implemented for the HQPT scheme. 1.3 HQPT is a fundamental element of the sustainable movement strategy and it is therefore crucial that the implementation of bus priority through the Stanborough Cross/Haye Road complex is well understood. Its operation in relation to the potential for the segregated Quarry Link connection is also discussed. 1.4 This document also deals with the TRANSYT comments and requests for evidence of bus operation from Plymouth City Council as per their letter of 28 th February Since the publication of Technical Note 11, a review of the signal control has been conducted and has supported changes to staging and intergreens, a revision to the layout and signalling at Haye Road, the results of which are reported within this revised Technical Note (v2) and TA Addendum. 1.6 Bus priority is not limited to the Stanborough Cross/Haye Road junction complex. For further details of bus priority to be provided along the entire Sherford Main Street has been discussed in more detail in Technical Note TN10 - Main Street Bus Priority. TN10 also provides clarification of the bus priorities discussed in this document. 1.7 However, it is also likely that the Technical Note TN08 Main Street Strategy will further inform, as part of the development of a micro-simulation model, the assignment of flows along the main street and the resultant signal control measures that are required to maintain bus priorities. As such the results presented in the TA Addendum are reflective of the worst case scenario which was detailed in the original TA submission. October

68 SHERFORD, PLYMOUTH TECHNICAL NOTE 11 (v2) STANBOROUGH CROSS OPERATIONAL REVIEW 2. STANBOROUGH CROSS TRANSYT 2.1 A number of queries were raised by Plymouth City Council in their letter of 28 th February The following section provides the additional information necessary to clarify the various elements highlighted. Flow 2.2 In line with standard practice, PCU flows have been utilised within the TRANSYT modelling. 2.3 The modelling data previously presented by the TA included a predicted flow representing the transit of HQPT through the Stanborough Cross junction complex, where a total of 50 PCUs was included in the modelling of Stanborough Cross. In line with the developing public transport strategy, this allowance has therefore now been revised to 18 PCUs (6 buses per hour) and is detailed by the TA Addendum. Saturation Flow 2.4 Saturation flow adjustment based on geometry has been applied to the right turn link (Link 121), as requested. Reducing the saturation flow from 2000 PCU/hr to 1888 PCU/hr, as well as the introduced operational changes, results in the following differences shown in TABLE 2.1. TABLE 2.1 TRANSYT Link 121 saturation flow update modelling impact TA TA Addendum Model DOS MMQ DOS MMQ AM With Quarry Link PM With Quarry Link AM Without Quarry Link PM Without Quarry Link Whilst differences can be seen between the updated results and those originally submitted, the changes in DOS (Degree of Saturation) are relatively insignificant and there is almost no perceivable change in the resultant queuing (MMQ Mean Max Queue). Queuing Plots 2.6 The queuing as displayed by the TRANSYT output has been applied to the junction layout, to scale based on 1 PCU being equal in length to 5.75m, in order to provide a visual representation of the indicative level of queuing expected during operation. FIGURES represent the queuing displayed by the TRANSYT models for the AM/PM With and Without the Bus Quarry Link scenarios. The quarry link approach displayed by FIGURES is indicative. 2.7 The queuing at Stanborough Cross has been modelled in such a way as to ensure that the capacity seen in the model can be realised on the ground. The following provides some clarity as to any assumptions made and how this relates to the actual operation of the junction. October

69 SHERFORD, PLYMOUTH TECHNICAL NOTE 11 (v2) STANBOROUGH CROSS OPERATIONAL REVIEW Elburton Road East A The straight ahead approach from Elburton Road East A379 (Link 122) whilst the layouts display 2 full lanes for the straight ahead approach, this has actually been modelled within TRANSYT as one full lane with a 10 PCU flare. This accounts for any right turners that may, for a small proportion of the green time, block one of the ahead lanes, and for left turners to access the left turn flare. 2.9 In addition, the queuing output for the right turn link would begin at the effective stopline in the central area of the junction where vehicles advance to from the actual stopline whilst giving way. Stanborough Road 2.10 With the introduction of this Technical Note (v2) the approach now runs in a dedicated stage. Elburton Road West A Straight ahead approach from Elburton Road West A379 (Link 142) in order to model the actual use of the 2 ahead lanes this link has been built as a full lane with an 8 PCU flare. This takes into account the effect of the high demand for the left turn in advance of the left turn flare shown on the layouts. Pedestrian Facilities 2.12 The pedestrian facilities provided as part of the proposals for the Stanborough Cross junction are currently modelled as being demanded every cycle. However, a pedestrian survey suggests that this would be unlikely in the actual operation of the junction The signal control of the junction allows for most of the pedestrian phases to be run alongside traffic phases. As this is not the case for the A379 western arm, this crossing needs to run in it own stage, although, the pedestrian survey undertaken on the 9 th May 2006, displayed by TABLE 2.2, identifies this arm as one of the least, pedestrian, trafficked crossings. TABLE 2.2 Stanborough Cross Pedestrian Survey Crossing 08:00-08:15 08:15-08:30 08:30-08:45 08:45-09:00 Haye Road A379 (E) Stanborough Road A379 (W) October

70 SHERFORD, PLYMOUTH TECHNICAL NOTE 11 (v2) STANBOROUGH CROSS OPERATIONAL REVIEW 3. STANBOROUGH CROSS BUS PRIORITY 3.1 Several bus priority measures are proposed for the Stanborough Cross and Haye Road junction complex in order to help support the aims of establishing reliable and robust public transport journey times. It is the intention that these priority measures will further promote the benefits of the bus over the car by providing visible priority aids. 3.2 On the approach to Haye Road from Sherford Main Street, a bus lane will facilitate the unhindered transit of buses to a bus gate. This will ensure that buses enter Haye Road at the front of any vehicular queue from the Sherford development. 3.3 The visionary scenario would be for buses to leave the current road network and enter a new Quarry Link, a specifically assigned and segregated bus route, where it would travel unrestricted until re-joining the A379 prior to Laira Bridge. A number of commitments are required in the delivery of such a scheme, implying that an interim situation also needs to show that sufficient bus priority can be facilitated through the Stanborough Cross junction. The proposed design is expected to deliver this with minimal disruption to the existing performance of the complex of junctions. 3.4 The bus gate would enable the Haye Road approach to Stanborough Cross to operate as a virtual bus lane by relocating vehicular queues from the Stanborough Cross signalised junction, where there is insufficient road width to install a physical bus lane, upstream to the Sherford Main Street where a bus lane is in place. 3.5 The virtual bus lane will enable the bus to pass the queuing vehicles on Sherford Main Street and through the bus gate to reach Stanborough Cross, where queuing will be maintained at a level that allows buses to pass through the junction within one cycle. 3.6 Selective Vehicle Detection (SVD) will complement the priority that buses receive ensuring that buses do not experience undue delay at the signalised junctions. The priority received will need to be implemented with care at the Stanborough Cross junction to protect opposing buses travelling along the A The use of hurry calls has also been investigated. Whilst the bus gate and quarry link junctions are a good potential for hurry calls and therefore green waves, due to their relative isolation and availability for stacking vehicles, these may not prove feasible at Stanborough Cross. A general overview of SVD can be found in the Technical Note TN10 - Main Street Bus Priority. 3.8 FIGURE 3.1 displays how a bus would progress through the proposed junction complex in the interim scenario. The figure shows the position of the bus at a number of points through time as it approaches Stanborough Cross and how it interacts with general traffic. It highlights that there is a point the cycle that is clear of traffic and that any bus travelling through the junction complex will clear within one cycle. October

71 SHERFORD, PLYMOUTH TECHNICAL NOTE 11 (v2) STANBOROUGH CROSS OPERATIONAL REVIEW FIGURE 3.1 Stanborough Cross Bus Progression 3.9 Assuming the absence of the Quarry Link, during the AM scenario the operation of the bus gate will introduce a delay of just over 6 minutes to private motor vehicles travelling via the Haye Road/Stanborough Cross complex whilst buses, even without the introduction of SVD would be delayed by, approximately 30 seconds, a substantially lower time Plymouth city centre bound buses at Stanborough Cross, with the implementation of the bus gate would be delayed by approximately 50 seconds (without the introduction of SVD). Conversely, if the bus gate was not installed, the delay would increase to approximately 3 minutes On the return leg to Sherford buses would be delayed by approximately 30 seconds at Stanborough Cross and by 60 seconds at the Haye Road/Sherford Access Road, both times quoted could be reduced with the introduction of SVD for the return leg The TRANSYT modelling for the Stanborough Cross section with the Quarry Link in place is fully optimised without constraint, however, to further enhance the perception of the HQPTs advantage some level of Sherford traffic queuing should still be relocated from Stanborough Cross to the bus gate at Haye Road/Sherford Main Street Access even with the Quarry Link in place. Although this queuing is relocated and traffic may witness more buses passing them, there would not necessarily be any additional delay to their passage through the section. October

72 SHERFORD, PLYMOUTH TECHNICAL NOTE 11 (v2) STANBOROUGH CROSS OPERATIONAL REVIEW 4. CONCLUSION 4.1 This document has shown that the modelling results reported by the TA and TA Addendum can accommodate the flows reported in both documents. 4.2 In response to modelling queries outlined by Plymouth City Council in their letter of 28 th February 2007, this document has provided clarity to any issues raised, made adjustments as required and reported any differences. 4.3 The queuing reported has been clearly displayed on layouts and the assumptions that allow the operation of the junction to be realised have been discussed. FIGURES provide detail of the proposed junction arrangements with expected queuing. 4.4 The operation of bus priority at the Stanborough Cross junction complex has highlighted the degree to which buses receive significantly more priority than private cars. The use of various priorities for buses have been reported which in line with the Technical Note 10 Main Street Bus Priority outlines the proposed methods for providing advanced access to buses. 4.5 A number of identified changes to the design and operation of the junction complex have been made; these have been reported and shown to have beneficial effects. In addition further benefits in the real time operation may be realised with the micro-simulation modelling due to various traffic and pedestrian demand dependency. October

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77 SCOTT WILSON SHERFORD, PLYMOUTH TECHNICAL NOTE 13 (V2): RED LION HILL JUNCTION TESTING Ref: D August 2007

78 Sherford, Plymouth Technical Note 13: Red Lion Hill Junction Testing Prepared by: Peter Wood Graduate Transport Planner Colin Romain Transport Planner Reviewed by: Checked and approved by: Kevin Kay Senior Transport Planner Sandy Burrell Technical Director Scott Wilson Scott House Basing View Basingstoke RG21 4JG Tel: +44 (0) Fax: +44 (0) Disclaimer This document has been prepared in accordance with the scope of Scott Wilson's appointment with its client and is subject to the terms of that appointment. It is addressed to and for the sole use and reliance of Scott Wilson's client. Scott Wilson accepts no liability for any use of this document other than by its client and only for the purposes, stated in the document, for which it was prepared and provided. No person other than the client may copy (in whole or in part) use or rely on the contents of this document, without the prior written permission of the Company Secretary of Scott Wilson Ltd. Any advice, opinions, or recommendations within this document should be read and relied upon only in the context of the document as a whole. The contents of this document are not to be construed as providing legal, business or tax advice or opinion. Scott Wilson Group plc 2006

79 SHERFORD, PLYMOUTH TECHNICAL NOTE RED LION HILL JUNCTION TESTING 1. INTRODUCTION JUNCTION TESTING CONCLUSION th August 2007 i

80 SHERFORD, PLYMOUTH TECHNICAL NOTE RED LION HILL JUNCTION TESTING 1. INTRODUCTION In 2006, Scott Wilson (SW) prepared a Transport Assessment (TA) in support of the Sherford Development, located to the east of the City of Plymouth, in Devon Following this, this Technical Note considers the re-design of the existing junctions of the A379 and Red Lion Hill, and the A379 and Winstone Lane. Currently both of these junctions comprise simple, uncontrolled priority junctions This Note will therefore present the results of the junction testing that has been undertaken under the 2016 Do Something scenario, assuming that mini roundabout junctions are constructed. 2. JUNCTION TESTING Traffic flow data for the AM and PM peak periods was obtained from onsite observations in June 2007 for the junctions, and annualised in accordance with the methodology employed in the TA These flows were then growthed to 2016 based on the methodology presented in the TA. In order to consider the Do Something situation however, it was necessary to add on the development traffic to the 2016 flows Based on the assumptions presented in the TA it was assumed that development traffic travelling to/from the development along Red Lion Hill would only travel to/from the site via A379 (east), as more attractive vehicular travel options are provided to/from the site to the west of Red Lion Hill (eg. Sherford Road). The combined 2016 Do Something predicted flows at the junctions are shown in FIGURE The proposed mini roundabout dimensions and predicted flows were used as inputs for the ARCADY software junction modelling program, which has been used to consider the likely operation of the proposed junction designs. The proposed layout of the junctions is shown in APPENDIX A The ARCADY analysis for the 2016 Do Something scenarios for the AM and PM peaks suggest that both of the junctions will operate well within the recommended capacity threshold (0.850) It is expected that the highest RFC (Ratio of Flow to Capacity) at the junction between the A379 and Red Lion Hill will occur on the A379 East during the AM peak (0.464). The corresponding queue is not expected to exceed one vehicle, assuming a random arrival profile of vehicles. The analysis suggests that, based on the tidality of traffic along the A379, that the operation of the junction would essentially reverse during the PM peak such that the highest RFC would then be expected to occur on A379 West (0.462). Again queuing would not be expected to exceed one vehicle The junction capacity tests for the A379/Winstone Lane indicate that the highest RFC will occur on A379 West during the PM peak (0.525), with an associated queue of 1.1 vehicles The ARCADY capacity results are summarised below in TABLE th August

81 SHERFORD, PLYMOUTH TECHNICAL NOTE RED LION HILL JUNCTION TESTING TABLE 2.1 Predicted RFC and Queue Length (Vehicles) A379 Mini Roundabouts 3. CONCLUSION Location AM Peak PM Peak A379 / Red Lion Hill RFC Queue RFC Queue A379 West Red Lion Hill A379 East A379 / Winstone Lane RFC Queue RFC Queue A379 East Winstone Lane A379 West This Technical Note has considered the potential redesign of the existing uncontrolled priority junctions at A379/Red Lion Hill and A379/Winstone Lane Traffic flows have been obtained from onsite surveys and have been factored to 2016, plus Sherford development traffic, in order to derive a 2016 Do Something scenario, as per the methodology set out in the Sherford TA The proposed junction designs have subsequently been tested using ARCADY in order to consider the likely operation of the proposed junctions. The analysis, reported in TABLE 2.1, suggests that both of the mini-roundabouts will operate within the recommended capacity threshold. The largest queue is expected to be 1.1 vehicles on A379 West (A379/Winstone Lane junction) during the PM peak. All other queues are expected to be below 1 vehicle. 30th August

82 62 81 Red Lion Hill Red Lion Hill Kitley View A379 (Chittleburn HIll) Winstone Lane AM Peak Period ( ) Kitley View Drawing Ref:K:\D Sherford\Drawings\Freehand\Movement Diagram for A379 by Red Lion Hill.FH PM Peak Period ( ) SHERFORD DO SOMETHING PEAK PERIOD TRAFFIC FLOWS Winstone Lane Figure: 2.1 Scale at A4: N/A Drawn GH Checked PW Approved KK Date 16/08/07 A379 (Chittleburn HIll) Revised N/A Date 16/08/07

83 Appendix A

84 Appendix A

85 SCOTT WILSON SHERFORD, PLYMOUTH SATURN MODEL SPECIFICATION Ref: D CAR6 August 2007

86 SHERFORD, PLYMOUTH Outline SATURN Model Specification Collated and edited by: Reviewed by: Approved by: Paul Kelly Transport Consultant Kevin Kay Senior Transport Consultant Sandy Burrell Technical Director Scott Wilson Scott House Basing View Basingstoke RG21 4JG Tel: +44 (0) Fax: +44 (0) Disclaimer This document has been prepared in accordance with the scope of Scott Wilson's appointment with its client and is subject to the terms of that appointment. It is addressed to and for the sole use and reliance of Scott Wilson's client. Scott Wilson accepts no liability for any use of this document other than by its client and only for the purposes, stated in the document, for which it was prepared and provided. No person other than the client may copy (in whole or in part) use or rely on the contents of this document, without the prior written permission of the Company Secretary of Scott Wilson Ltd. Any advice, opinions, or recommendations within this document should be read and relied upon only in the context of the document as a whole. The contents of this document are not to be construed as providing legal, business or tax advice or opinion. Scott Wilson Group plc 2006

87 SHERFORD OUTLINE SATURN MODEL SPECIFICATION 1. INTRODUCTION 1.1 In 2006, Scott Wilson (SW) prepared a Transport Assessment (TA) in support of a new sustainable development at Sherford, located to the east of the City of Plymouth, in Devon. 1.2 Following a series of consultation meetings and correspondence with the Highways Agency, they have requested the submission of the modelling files involved with the SATURN modelling of the internal Sherford network. 1.3 This note accompanies the submitted files and provides an outline specification for the SATURN model used to deliver the internal assignment of trips presented within the TA. 1.4 It is crucial, however, that the use of the SATURN model, however, is seen within the context of its scope in relation to the Transport Assessment and how it has developed to provide a basis for setting the strategy to manage the flow of traffic along the High Street, in line with Technical Note 8: Main Street Strategy. 2. SPECIFICATION 2.1 The Sherford development was divided into 55 geographic zones to reflect the general land use for each development parcel and to ensure that a detailed reflection of traffic loading was achieved across the internal network. Only one or two centroid connectors were used per zone. 2.2 The SATURN model itself is based on the Enquiry by Design layout and on the Prince s Foundation s internal highway network hierarchy, as shown in FIGURE 12.1 of the TA. As part of these inputs, five different link types were identified and coded into the network, based on the relative relationships between then in terms of their type, speeds and capacities were assigned to each. The five link types were as follows: 1. High Street 2. Main Connector Links (e.g. north and south distributors) 3. Secondary Roads (provide access to land parcels) 4. Access Roads (localised access) 5. Minor Roads 2.3 The first three levels of roads have been fully taken account of in the SATURN model. Some Access and Minor roads were included where these gave access to areas of significance such as the schools or healthcare centre. 2.4 The proposed new Haye Road link was also coded into the model, including the signal control between it and Stanborough Cross. All other connections with the existing highway network were retained. 2.5 The assignment of internal vehicular trips was made on the basis of a buffer network, to allow the most logical loadings to occur across the network. All the main junctions along the Main Street were originally coded as simulation dummy nodes. The purpose of which was to allow turning movements to be drawn from the model and utilised for detailed junction capacity testing. 20 th August 2007

88 SHERFORD OUTLINE SATURN MODEL SPECIFICATION 2.6 This flow information was input into the detailed junction capacity assessments to establish the workability of the junction designs. In reality, a degree of control will be afforded by junction configuration, the effect of which can be represented in the same way. 2.7 Technical Note 8: Main Street Strategy details how the SATURN model was further developed to provide a strategy for the assignment of traffic on the competing routes of Main Street and Northern/Southern Avenues in delivering an environment conducive to the development of a vibrant High Street. 2.8 The detailed junction configuration information was input into the SATURN to reflect the effect of junction configuration on the assignment. These sets of signals were also optimised to minimise delay across the network and provide for a degree of iteration between the two platforms. However, the junction settings which incorporated a bus priority bias were not subject to optimisation (e.g. Stanborough Cross/Haye Road, School Loop) to restrict the ability of the SATURN model to optimise these locations based on a benefit to vehicles. 2.9 The network also encompasses the Stanborough Cross and Elburton Junctions. These have been coded as a signalised junction and roundabout respectively Eight geographic zones were coded into the model, external to the Sherford network to enable the loading of traffic onto the aforementioned links for external and through traffic trips. The zones are shown in FIGURE The derivation of the matrices that feed into the process of assigning existing through-traffic was covered by Technical Note 9: Through Traffic Matrix Development. The assignment of Sherford traffic was done on the basis of the methodology set out in the TA. 20 th August 2007

89 Drawing Ref:K:\D Sherford\Drawings\Freehand\Origin Destination Matrix Cordons from Network for Saturn Report.FH11.1 A379 West 1006 SHERFORD ORIGIN DESTINATION SATURN ID S Sherford Road A379 Elburton Road Vinery Lane A38 Plympton Hill 1004 A38 West 1003 Stanborough Cross South 1013 Elburton South 1014 Haye Road 1005 Elburton 1011 A379 East 1012 Brixton Road 1010 A38 Figure: 1 Scale at A4: N/A Drawn GH Checked PK Approved KK Date 16/08/07 Deep Lane North of Deep Lane 1002 DLN East 1015 Local East 1009 Revised 1 Date 16/08/07 A38 East

90 SCOTT WILSON SHERFORD NEW COMMUNITY MAIN STREET MICRO-SIMULATION Ref: D CAR26 October 2007 Scott Wilson Scott House Basing View Basingstoke RG21 4JG Tel: +44 (0) Fax: +44 (0) Disclaimer This document has been prepared in accordance with the scope of Scott Wilson's appointment with its client and is subject to the terms of that appointment. It is addressed to and for the sole use and reliance of Scott Wilson's client. Scott Wilson accepts no liability for any use of this document other than by its client and only for the purposes, stated in the document, for which it was prepared and provided. No person other than the client may copy (in whole or in part) use or rely on the contents of this document, without the prior written permission of the Company Secretary of Scott Wilson Ltd. Any advice, opinions, or recommendations within this document should be read and relied upon only in the context of the document as a whole. The contents of this document are not to be construed as providing legal, business or tax advice or opinion. Scott Wilson Group plc 2006

91 Sherford, Plymouth Main Street Micro-Simulation Prepared by: Paul Kelly Graduate Transport Planner Mattias Stridh Assistant Transport Planner Reviewed by: Checked and approved by: Kevin Kay Senior Transport Planner Sandy Burrell Technical Director Scott Wilson Scott House Basing View Basingstoke RG21 4JG Tel: +44 (0) Fax: +44 (0) Disclaimer This document has been prepared in accordance with the scope of Scott Wilson's appointment with its client and is subject to the terms of that appointment. It is addressed to and for the sole use and reliance of Scott Wilson's client. Scott Wilson accepts no liability for any use of this document other than by its client and only for the purposes, stated in the document, for which it was prepared and provided. No person other than the client may copy (in whole or in part) use or rely on the contents of this document, without the prior written permission of the Company Secretary of Scott Wilson Ltd. Any advice, opinions, or recommendations within this document should be read and relied upon only in the context of the document as a whole. The contents of this document are not to be construed as providing legal, business or tax advice or opinion. Scott Wilson Group plc 2006