Stamford Traffic and Highway Study

Stamford Chamber of Trade & Commerce

Stamford Traffic and Highway Study Technical Note 1 – Report of Survey

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Stamford Chamber of Trade & Commerce

Stamford Traffic and Highway Study

Technical Note 1 – Report of Survey

Belfast Brighton Glasgow Leeds Lichfield Liverpool London Manchester Newcastle upon Tyne CONSULTING

JMP CONSULTING MINERVA HOUSE, EAST PARADE LEEDS LS1 5PS T 0113 244 4347 F 0113 242 3753 E [email protected] W www.jmp.co.uk Job no. Prepared by Verified Approved by Status Issue no. Date

D057011 EW/ET PC Final 1 Feb 2005

http://www.jmp.co.uk/

Stamford Traffic and Highway Study Technical Note 1 – Report of Survey Contents Amendment Record This document has been issued and amended as follows:

Status/Revision Issue Number Date Approved By Draft 1 Dec 2004 PC Draft 2 Jan 2005 PC Final 1 Feb 2005 PC


Contents

1 Introduction 1 Background 1 Requirement for Survey Work 1 Report Content 1

2 Data Collection 2 Turning Count Surveys 2 Automated Turning Counts (ATC) 2 Journey Time Surveys 3

3 Data Analysis 5 Introduction 5 Junction Turning Counts 5 Automated Traffic Counts 5 Journey Time Surveys 5

4 Summary 8

Appendices

Appendix A Survey Locations

Appendix B Junction Counts

Tables and Figures Table 3.1 Accuracy of Journey Time Surveys (Table 11/1 From DMRB Vol 13) 6 Table 3.2 AM Peak Accuracy Test 6 Figure 3.1 Journey Time Validation Graph 7

Figure 2.1: Location of Surveys

Figure 2.2: Routes Surveyed


1 Introduction Background

1.1 In July 2004 JMP Consulting was appointed by Stamford Chamber of Trade and Commerce to undertake the Stamford Traffic and Highway Study. The study considers the provision of a Relief Road to remove ‘through – traffic’ from Stamford, to provide alternative routes away from the points of constraint and to provide access to development sites included in the South Kesteven District Council (SKDC) Local Plan. The study assesses the transport infrastructure requirements to support development opportunities within Stamford in the short, medium and long term.

Requirement for Survey Work 1.2 A calibrated and validated base model was required to assess the impacts of any

transport infrastructure changes proposed as part of the study. JMP Consulting developed a SATURN traffic model of Stamford in 1989 and it was proposed that this model should be updated to reflect present traffic conditions rather than to develop a new model. The model is described in Technical Note 2 – Local Model Validation Report.

1.3 The information required to develop the model included the highway and junction characteristics, observed traffic flows, trip origins and destinations and journey times. This data was collected through various traffic surveys and concentrated on the morning traffic period, which had the greater overall traffic volume and effect on key links and junctions.

1.4 The newly acquired data was used to update and recalibrate and validate the traffic model in accordance with the guidance set out in the Department for Transport’s Design Manual for Roads and Bridges (DMRB).

Report Content 1.5 This report is a technical note detailing the survey work undertaken for the project, the

methods used and outcomes of the data analysis.

1.6 The following types of survey were undertaken:

Classified turning counts; • • •

Automated traffic counts; and Journey time surveys.

1.7 Each of the survey types will be discussed in turn. The result of the data analysis is then

considered and conclusions for the survey drawn.

D57011 Stamford Traffic and Highway Study Ref: Technical Note 1 – Report of Survey Final

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2 Data Collection

Turning Count Surveys Introduction

2.1 Although a number of junctions within Stanford town centre had been surveyed between 2001 and 2004, in order to produce an accurate base traffic model for Stamford, turning movements were required at a number of other junctions where current data was more than four years old. The data was used to recalibrate the existing, older model.

Survey Specification

2.2 JMP Consulting issued a survey specification to a number of survey companies to obtain quotes for the Turning Count Surveys and the Automated Traffic Counts (see below).

2.3 Three quotes were received and JES Surveys were chosen to undertake the work, based on quality of the tender, the quote and understanding of the specification. JMP Consulting has used JES Surveys on numerous occasions.

Survey Requirements

2.4 16 junctions were manually surveyed over the three-hour AM peak period (0700-1000) on two consecutive week days, not including Mondays and Fridays. All junctions were surveyed on the same two days so all the data used in the model was congruent. In Appendix A, Table 2.1 gives the names of the junctions surveyed and Figure 2.1 shows their locations.

2.5 The specification requested that the junction turning counts be undertaken on days coinciding with the seven day ATC surveys between the 13th September and 4th October 2004, to ensure that model data was compatible.

2.6 The classification breakdown required for each junction survey was requested as follows:

Light Vehicles (Car, Taxi, LGV); and • • Heavy Vehicles (OGV, HGV, not including Buses and Coaches)

2.7 For each junction, a spreadsheet was provided tabulating the classified traffic turning count for each traffic movement for each fifteen minute interval of the survey period. Hourly totals by class and for total traffic and survey period totals were also included.

Observed Problems

2.8 Site 8, Conduit Road/New Cross Road, Conduit Road South had been closed for 9 weeks from the 23rd August 2004. Although traffic was present there may be a reduced traffic presence at the junction overall as well as there being no traffic on Conduit Road.

2.9 There were no other problems reported during the surveys or encountered with the output data during analysis.

Automated Turning Counts (ATC) Introduction

2.10 The SATURN base traffic model requires link flow data to ensure an accurate model; therefore, a number of temporary ATC counters were placed on key links to determine the scale of daily and hourly variations in traffic flows. Some of the ATC data will be used to update the base year matrices whilst others will be used to validate the base year model.


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Survey Specification

2.11 JMP Consulting issued a survey specification to a number of survey companies to obtain quotes for the Turning Count Surveys (see above) and the Automated Traffic Counts.

2.12 Three quotes were received and JES Surveys were chosen to undertake the work, based on quality of the tender, the quote and understanding of the specification.

Survey Requirements

2.13 16 ATC surveys were undertaken over a period of 7 days recording traffic levels in both directions at each site. A list of ATC sites included in the survey is given in Appendix A, Table 2.2 and the locations of the sites given in Figure 2.1.

2.14 The specification requested that the ATC counts be undertaken on days coinciding with the two day turning count surveys between the 13th September and 4th October 2004, to ensure that model data was compatible.

2.15 The classification breakdown required for each ATC survey was requested as follows:

Light Vehicles (Car, Taxi, LGV); and • •

•

• •

Heavy Vehicles (OGV, HGV not including Buses and Coaches).

2.16 For each site, the specification requested that the classified ATC hard data should be presented in tabular format showing:

Hourly totals for the three peak periods; AM (0700-0900), Inter (1100-1400) and PM (1600-1900) for each day; Total 12 hour traffic flow (0700-1900 hours) for each day; and Total daily traffic flow (24 hour).

Observed Problems

2.17 During the survey it was found that it was not possible to attach an ATC to Broad Street. The dense parking and wide highway at this point would mean that vehicles would not be detected correctly and the data would not be accurate. This site was abandoned.

2.18 An ATC on Wharf Road was vandalised part way through the survey week but was replaced as soon as possible to minimise the effect on data collection. This was not a problem as there were 5 full days of traffic flows to utilise.

2.19 There were no other problems reported during the surveys or encountered with the output data during analysis.

Journey Time Surveys Introduction

2.20 Journey time surveys were undertaken for the validation of the base traffic model only. Observed journey times are compared with the modelled journey times to assess the accuracy of the traffic model in accordance with the guidance set out in the Department for Transport’s Design Manual for Roads and Bridges (DMRB).

Survey Description

2.21 The journey time surveys were undertaken over two consecutive weekdays in September, coinciding with both the turning count and ATC surveys performed by JES, to ensure compatibility of data within the model.


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2.22 Four routes were surveyed in total and these are shown on Figure 2.2. Each route was surveyed for one hour of each AM peak period, therefore giving 2 hours of journey time data for each route over the two day survey. The surveys were undertaken with video camera so there was no requirement for more than one person in each car.

Survey Requirements

2.23 The traffic appraisal guidance in DMRB Volume 13 recommends journey time measurements are undertaken at the traffic modelling stage, using the most widely used moving observer method. The journey time surveys were planned and undertaken by JMP staff.

2.24 The guidance gives advice on obtaining accurate journey time data which is related to the range of journey times on one route and the number of runs on each route. This is discussed in more detail in section 3.

Observed Problems

2.25 On route D, the camera battery expired within the first run of the allotted hour time-frame. Thus, there were very few runs captured on camera. This reduced the accuracy of the journey time data. This is discussed further in the next section.

2.26 No further problems were reported.


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3 Data Analysis Introduction

3.1 Following the surveys, it was necessary to analyse the data collected for entering into the base year traffic model or to validate the model. Data taken from the commissioned surveys required less analysis than the journey time surveys.

3.2 This section discusses each type of survey, how the data was analysed and then added to the model. Assessment of data accuracy is discussed where required.

Junction Turning Counts 3.3 As the 16 junction surveys were undertaken over two days each for a three hour period

(0700 to 1000), the peak hour was determined as 0800 to 0900. This was taken forward and used for matrix estimation, the process of updating the model based on new count data.

Automated Traffic Counts 3.4 The automated traffic counts provided data for 5 classifications of vehicle over 7 days at

16 different sites. Again for use in the model the AM peak flow was utilised and used in both matrix estimation and network validation.

Journey Time Surveys Data Analysis

3.5 After the surveys had been undertaken the data was extrapolated to find the average journey time in the AM peak.

3.6 For each route a number of timing points were identified at junctions of significance encountered during each journey, the purpose of timing these separately was to accurately identify the amount of time taken to travel each link.

3.7 The observed average journey times for each route were subsequently taken forward for comparison with the modelled times in order to identify accuracy. The comparison of observed and modelled times is displayed in the following paragraphs.

Data Accuracy

3.8 The appraisal guidance gives methods for ensuring accuracy of journey time data to an appropriate degree of confidence.

3.9 It is realistic to aim for an accuracy of +/- 10% on the existing route at the 95% confidence level. In order to do this, the coefficient of variation of the journey time runs should be calculated. The relationship between these factors is shown below in Table 3.1.

3.10 This is based on Student’s t-distribution assuming that observed journey times are normally distributed, where the accuracy (a) is dependent on the standard deviation (s), the mean journey time (m) and the number of runs performed (degrees of freedom).


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Table 3.1 Accuracy of Journey Time Surveys (Table 11/1 From DMRB Vol 13)

Number of Journey Time Runs Coeff. of Variation of Observed Journey Times

(CV = (s/m)*100) % For a = 10% = 1/10 For a = 20% = 1/5

5 4 2

10 7 2

15 11 3

20 18 5

30 35 9

40 64 16

50 100 25

3.11 It can be observed that it is difficult to know how many runs are required to be confident of a specific accuracy prior to the surveys. The accuracy could only be determined after the surveys were undertaken.

3.12 This analysis was undertaken for journey time survey results following completion of the surveys, the following table displays these results:

Table 3.2 AM Peak Accuracy Test

Route & Direction

Observed Max

Observed Min

Standard Deviation

Diff to

Max

Diff to

Min Observed

Mean Modelled Validated A EB 378.0 135.0 78.6 176.0 67.0 202.0 158.0 OK A WB 231.0 133.0 27.2 62.0 36.0 169.0 157.0 OK B NB 423.0 324.0 41.8 46.0 53.0 377.0 504.0 B SB 637.0 308.0 151.5 262.0 67.0 375.0 445.0 OK C EB 627.0 390.0 117.3 126.0 111.0 501.0 430.0 OK C WB 758.0 377.0 163.0 224.0 157.0 534.0 492.0 OK D EB 553.0 418.0 67.6 86.0 49.0 467.0 502.0 OK D WB 850.0 414.0 192.0 319.0 117.0 531.0 521.0 OK

(Journey time in seconds) 3.13 These results are presented on the next page (Figure3.1).

3.14 It would appear that four of the eight journeys (one for each of the four routes) were not accurate to the 20% confidence level. The large variations in journey times over one route and the low number of journeys undertaken accounts for this inaccuracy. Route D will have been affected by the low number of runs recorded due to a technical fault.

Model Validation

3.15 The base year traffic model is validated by comparing the observed (survey) journey times with those predicted by the model. When validation was attempted, seven of the eight journeys were to the accuracy required by the guidance, despite the lack of confidence in the observed journey time behaviour. The guidance requires that 85% of journeys validated be within 15% of the observed journey times and therefore the model validates.


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Figure 3.1: Journey Time Validation - AM Peak

0

100

200

300

400

500

600

700

800

900

0 1 2 3 4 5 6 7 8

Journey

Tim

e (s

econ

ds)

9

Observed Mean Modelled


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4 Summary Introduction

4.1 This Technical Note described the surveys undertaken to produce and validate a base year SATURN traffic model for Stamford. The report outlines the requirement for and procedures for undertaking the surveys and discusses data use and accuracy.

Problems Encountered

4.2 Very few problems were encountered during the survey period for any of the commissioned surveys. The data collected is sound and has been utilised within the model. All problems that occurred were beyond the survey company’s control and that of JMP Consulting. They have not affected the accuracy of the model in any way.

4.3 The journey time surveys may have more of an impact and this is discussed.

Accuracy

4.4 The time available to undertake the journey time surveys gave two hours of data per route and logically, one hour of journeys in either direction on that route. This does not allow for many journeys to be recorded and the large variations in journey times due to the congestion in Stamford meant that there was quite a variation in the results of the journey time surveys.

4.5 The number of runs undertaken was also affected by technical faults when runs were not recorded due to battery failure.

4.6 The accuracy of the surveys will have an affect on the accuracy of the model, but the model validates to the appraisal guidance indicating that it is acceptable for its purpose.

Conclusion

4.7 All the survey work associated with this project has been undertaken satisfactorily and to an appropriate standard.


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Figures

Figure 2.1 Locations of Surveys Figure 2.2 Routes Surveyed

Appendix AJunction Survey

Locations

Note: Survey Location Numbers correspond to those given in Figure 2.1. Table A1 Junction Turning Counts Survey Location Number Number of Arms Survey Junction

1 3 B1081 Casterton Road/Charlock Drive 2 3 A606 Empingham Road/Arran Road 3 3 B1081 Casterton Road/Sutherland Way 4 3 A606 Empingham Road/Waterfurlong 5 3 B1081 Casterton Road/Little Casterton 6 3 Radcliffe Road/New Cross Road 7 4 A6121 West Street/B1081 Scotgate 8 4 New Cross Road/Conduit Street 9 3 Lincoln Road/Kesteven Road

10 3 A6121 Ryhall Road/Drift Road 11 4 A43(T) High Street St Martin/Water Street 12 4 Little Casterton Road/Waverley Gardens 13 3 A6121 East Street/Recreation Ground Road 14 3 A43(T) Kettering Road/B1081 Old Great North Road 15 4 Barn Hill/St Peter’s Street (withdrawn) 16 3 St Peter’s Street/Sheep Market

Table A2 ATC Survey Locations Survey Location Number Location of ATC Survey Direction

1 B1081 Casterton Road at Belvoir close SE and NW 2 A606 Empingham Road, west of Dickens Drive W and E 3 A6121 Tinwell Road, west of Exeter Gardens SW and NE 4 A43 (T) Kettering Road, north of 2nd Drift SW and NE 5 B1081 Old Great North Road, south of 1st Drift SE and NW 6 B1443 Barnack Road W and E 7 A16(T) Uffington Road, west of Priory Road W and E 8 A6121 Ryhall Road, north of Lincoln Road N and S 9 Kesteven Road, south of Masterton Road N and S 10 Green Lane Road, south of Edinburgh Road N and S 11 Cambridge Rd/Edinburgh Rd, south of Churchill Road W and E 12 Little Casterton Road, south of Cambridge Road SE and NW 13 A16 (T) Wharf Road, south of St Paul’s Street N and S 14 A16(T) Wharf Road, west of Albert Road SW and NE 15 A6121 Tinwell Road, west of junction with West Street SW and NE 16 Broad Street, west of Ironmonger Street (withdrawn) W and E

Appendix BJunction Counts

SITE ONEB1081 CASTERTON RD/CHARLOCK DRIVEAM peak Casterton Rd B1081W

173 2884 6

1174

692

Charlock Drive

KeyCar 43HGV 1

108 2523 9

Casterton Rd B1081 E

SITE TWOA606 EMPINGHAM ROAD/ ARRAN ROADAM peak A606 Empingham Rd E

32 2610 5

921

1390

Arran Rd

KeyCar 43HGV 1

65 2512 9

A606 Empingham Rd W

SITE THREEB1081 CASTERTON RD/SUTHERLAND WAYAM peak

B1081 W

19 3290 10

150

1411

Sutherland Way

KeyCar 43HGV 1

108 2402 11

B1081 ESITE FOURA606 EMPINGHAM WAY/WATERFURLONGAM peak Empingham Rd W

170 2191 10

441

61

Waterfurlong

KeyCar 43HGV 1

15 1420 1

Empingham Rd E

SITE FIVEB1081 CASTERTON ROAD/LITTLE CASTERTON ROAD AM peak B1081 E

49 1141 10

1062

923

Little Casterton Rd

KeyCar 43HGV 1

145 3212 6

B1081 WSITE SIXRADCLIFFE ROAD/NEW CROSS ROADAM peak Radcliffe Rd S

13 361 3

331

872

New Cross Road

KeyCar 43HGV 1

134 652 2

Radcliffe Rd N

SITE SEVENA6121 WEST STREET/B1081 SCOTGATEAM Peak

B1081 Scotgate W

3 5 1155 34 243 138

1256

1333

1

A6121 West St S A6121 West St N

14512

Key 188Car 43 6HGV 1 81

59 58 30 55 4 4

B1081 Scotgate E

SITE EightNew Cross Road/Conduit RdAM peak Conduit Rd N

142 232 2

1613

160

New Cross Rd

KeyCar 43HGV 1

11 160 2

Conduit Rd S

SITE NINELINCOLN ROAD/KESTEVEN ROADAM peak Kesteven Rd S

27 341 1

511

731

Lincoln Rd

KeyCar 43HGV 1

73 731 1

Kesteven Rd NSITE TENA6121 RYAHLL ROAD/DRIFT ROADAM peak Ryhall Rd N

55 4852 22

411

2094

Drift Rd

KeyCar 43HGV 1

137 2244 16

Ryhall Rd S

SITE ELEVENA43(T) HIGH STREET ST MARTIN/WATER STAM Peak

A43 N

1 13 2181 67 559 80

161

131

Station Rd Water St

670

Key 7Car 43 0HGV 1 9

15 309 1 011 17 1

A43 S

SITE TWELVELITTLE CAST'N RD/WAVERLEY GARDENSAM Peak

Little Casterton Rd N

5 5 0142 140 120 7

220

190

Waverly Gardens Lambeth Walk

Key 8Car 43 0HGV 1 3

08

14 63 7 00 3 1

Little Casterton Rd S

SITE THIRTEENA6121 EAST STREET/RECREATION GROUND ROADAM peak A6121 E

70 29597 1 27

2

1091

Recreation Ground Rd

KeyCar 43HGV 1

96 3403 26

A6121 WSITE FOURTEENA43 KETTERING RD/B1081 OLD GT NTH RDAM peak A43 N

84 2161 5

14513

572

A43 Kettering Rd

KeyCar 43HGV 1

280 34413 6

B1081 S

SITE FIFTEEN BARN HILL/ST PETER'S STREET WAS WITHDRAWN FROM THE SURVEY

SITE SIXTEENST PETER'S STREET/SHEEP MARKETAM peak

St Peter's St E

36 472 1

81

863

Sheep Market

KeyCar 43HGV 1

158 1602 3

St Peter's St W

CENTRUM HOUSE, 38 QUEEN STREET, GLASGOW G1 3DX

T 0141 221 4030 F 0141 221 4050E [email protected] W www.jmp.co.uk

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BLACKFRIARS HOUSE, PARSONAGE, MANCHESTER M3 2JA

T 0161 831 5600 F 0161 831 5601 E [email protected] W www.jmp.co.uk

CASTLE CHAMBERS, 43 CASTLE STREET, LIVERPOOL L2 9SH


TAME HOUSE, WELLINGTON CRESCENT, FRADLEY PARK, LICHFIELD, STAFFORDSHIRE WS13 8RZ


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