Integrated Traffic Management at Junction 33 of the M1 Evaluation Report
Total Page:16
File Type:pdf, Size:1020Kb
Integrated Traffic Management at Junction 33 of the M1 Evaluation Report Integrated Traffic Management at Junction 33 of the M1 Evaluation Report JOB NUMBER: 5035805 DOCUMENT REF: 5035805 04 02 022 Evaluation Report. 03 Initial Issue KA Butler JJ Steed SR Fradd JJ Steed July 08 02 Draft for HA Approval KA Butler - JJ Steed JJ Steed June 08 01 Draft for HA Comment KA Butler A Maher / PA JJ Steed JJ Steed May 08 Leach Originated Checked Reviewed Authorised Date Revision Purpose Description INTEGRATED TRAFFIC MANAGEMENT AT JUNCTION 33 OF THE M1 Evaluation Report Contents Section Page Executive Summary iv 1. Introduction 1 1.1 Evaluation Area 2 1.2 Evaluation Goals and Aims 2 1.3 Evaluation Scenarios 3 2. Evaluation Method 5 2.1 Periodicity and Data Selection 5 2.2 Motorway (MIDAS) Data 6 2.3 Journey Time Data 7 2.4 Automatic Traffic Counter (ATC) Data 9 2.5 Ramp Metering and Traffic Controller Data 10 2.6 Incident and Weather Data 10 2.7 Incident Data 10 2.8 HANET data 11 3. Relevant Events and Evaluation Timeline 12 3.1 Major and Long-term Events during ITM Evaluation 12 3.2 Evaluation Timeline 13 4. Data Analysis - ITM Activation 15 4.1 Traffic Trends in Evaluation Area 15 4.2 Journey Time through Junction 33 15 4.3 Volume on the Local Road Network 18 4.4 Journey Time Data 18 4.5 Impact of ITM on the Motorway Southbound Carriageway 26 4.6 Improvements to the Mainline Flow 28 4.7 Cost Benefit Analysis 29 4.8 Benefits 31 5. Conclusions 34 5.1 Introduction 34 5.2 Journey Time Savings 34 5.3 Stakeholder Involvement 35 5.4 Technology 35 i 5035805.04.02.022 Evaluation Report V03 30Jul08.doc INTEGRATED TRAFFIC MANAGEMENT AT JUNCTION 33 OF THE M1 Evaluation Report 5.5 Recommendation 36 Glossary 37 Appendix A – Statistical Tools 38 Appendix B – ATC Volume Charts 44 Appendix C – Journey Time Histograms 49 Appendix D – Traffic Signal Controller Configuration 78 Appendix E – Scenario A Traffic Trends 81 Appendix F - Lessons Learnt Report 89 1. Introduction 89 1.1 Purpose 89 1.2 Governance 89 1.3 Background 89 2. Lessons Learnt 90 2.1 The Steering Group 90 2.2 Project Issues 90 ii 5035805.04.02.022 Evaluation Report V03 30Jul08.doc INTEGRATED TRAFFIC MANAGEMENT AT JUNCTION 33 OF THE M1 Evaluation Report List of Tables Table 2.1 – ANPR Link Details 7 Table 2.2 – Implications of Parameter Value Change for Journey Times 9 Table 3.1 – Evaluation Timeline 14 Table 4.1 – Journey Time Analysis 20 Table 4.2 – Weighted Averages 24 Table 4.3 – Ramp Metering Evaluation Results 27 Table 4.4 – ITM Costs 30 Table 4.5 – Indicative Benefits 32 List of Figures Figure 1.1 – ITM Evaluation Area 2 Figure 2.1 – Data Validity Flow Diagram 6 Figure 2.2 – ANPR Camera Locations 7 Figure 2.3 – ATC Locations 9 Figure 3.1 – ITM Project Timeline 13 Figure 4.1 – Comparison of Average Journey Time Northbound 16 Figure 4.2 – Comparison of Average Journey Time Southbound 17 iii 5035805.04.02.022 Evaluation Report V03 30Jul08.doc INTEGRATED TRAFFIC MANAGEMENT AT JUNCTION 33 OF THE M1 Evaluation Report Executive Summary Integrated Traffic Management (ITM) requires the commitment of both the local authorities and the Highways Agency to seek improvements in traffic management at the boundary of the motorway and the all-purpose road network. The technical approach integrates the operation of ramp metering with the operation of the adjacent traffic signal controller to better manage the combined network. However, ITM also includes other improvements delivered through a combined and equitable approach to network improvement by all parties As such, integration applies not only to the technical aspects of the project but the institutional integration necessary to achieve the desired objective. The holistic approach to implementing ITM at a pilot site, Junction 33 of the M1 near Sheffield and Rotherham has been successful. Benefits have been demonstrated on both the motorway and local road network. Critical to the successful operation of ramp metering is the management of the queues generated on the slip road. Local authorities are naturally concerned that queues should not extend beyond the end of the slip road. At Junction 33, the traffic signals were configured to operate more efficiently and also to respond to data messages derived at the ramp metering controller indicating the extent of measured queue lengths on the metered slip road. The practical application of ITM is to adjust incrementally the flow arrival rate of traffic at the slip road to manageable platoon sizes. Ramp metering only operates in the evening peak period when it is needed but improvements to the local signals provide benefits throughout the day. Ramp metering was installed on the southbound motorway entry slip road of the M1 at Junction 33 in early 2007. In an independent evaluation1 of ramp metering operation in September 2007, journey times on the southbound motorway carriageway improved with a saving in evening peak journey times of 9.1%. This benefit was reassessed following ITM switch-on and the measured journey time saving was 14.7% compared to the state before ramp metering was introduced. Whilst some of this benefit may be attributed to ITM, some of the measured benefit could be attributed to other changes in the motorway network. Journey times on the local road network have decreased since the introduction of ITM. The overall weighted average journey time saving over a 24 hour period for traffic on the local road network was 8.7%. During the peak evening period when ramp metering and ITM were operating, this figure improves the journey time saving to 9.8%. These results indicate that the local roads and the motorway traffic both benefit from the introduction of ITM. One would expect an element of queue redistribution and thus some delay penalty to one type of user over the other. The positive results may be explained by the considerable effort that went into validating the traffic signals and recalibrating the ramp metering to allow for the introduction of the ITM link between the two systems. Improvements in these individual systems have attributed to much of the benefit measured. The ITM approach of cooperative working also delivered a number of other qualitative benefits such as an improved maintenance regime; improved road markings; and, a legacy from the evaluation exercise of permanent real time motorway data and video surveillance of 1 “Ramp Metering Operational Assessment” March 2008, Atkins document number 5063147_04_02_027 Issue 4 iv 5035805.04.02.022 Evaluation Report V03 30Jul08.doc INTEGRATED TRAFFIC MANAGEMENT AT JUNCTION 33 OF THE M1 Evaluation Report the junction available to the local authority. Other improvements are planned to use this data to influence traffic flows further from the immediate network around Junction 33. The original intention of the pilot was to evaluate ITM with MOVA, a dynamic traffic control strategy. However, protracted local planning issues outside the control of this project precluded this. Had the traffic signal controller been operating MOVA, the traffic arrival rate at the metered stop line would tend to be more variable. Fixed time plans operating at Junction 33, do not allow sufficient variability for the ITM control loop to influence the behaviour of the signals in the same way that might be expected if a more variable traffic control strategy were operating. It is therefore a recommendation of this report that ITM should be trialled on a similar network operating the dynamic traffic signal control strategy. During the course of the project great emphasis was placed on cooperative working between the various stakeholders which as a whole has contributed to the success of the ITM Pilot Project. v 5035805.04.02.022 Evaluation Report V03 30Jul08.doc INTEGRATED TRAFFIC MANAGEMENT AT JUNCTION 33 OF THE M1 Evaluation Report 1. Introduction The primary objectives of the Highways Agency and the other highway authorities often conflict. The Agency aims to provide an efficient highway network for longer distance travellers and freight whilst the local authorities look to cater for local residents and businesses. This conflict of interest is most apparent at the interface of the two networks. A range of traffic management techniques are used to optimise the capacity of the strategic network. One such technique is ramp metering. By metering the rate at which traffic joins the main carriageway from a slip road at a junction the mainline flow remains stable and less congested. Whilst there is a slight additional delay to traffic on the slip road itself, this is more than offset by the maintenance of steady and stable traffic flows achieved on the main carriageway2. This consequently provides benefits to both the strategic and local road networks. However, the success of ramp metering is sometimes limited by the capacity of the slip road to ‘store’ the metered traffic Integrated Traffic Management (ITM) seeks to address this issue by: “the integrated application of existing traffic management techniques on national strategic routes and the associated network corridor of adjacent roads and interchanges to manage access to, and from, the strategic route network by optimising vehicle delay in the combined strategic and local road network”.3 ITM, as implemented at M1 Junction 33, has sought to integrate the traffic signal control of the all-purpose network directly to the ramp metering of the southbound access slip road to the M1 main carriageway. At its inception, ITM was expected to provide additional ‘storage’ capacity at the junction to enable the more efficient use of ramp metering.