Traffic Signal Management Plans
Chapter 4. Outline for Traffic Signal Management Plans
Although the practical plan development process described above tends to work bottom up from the tactics to strategies, the plan should be organized in a logical fashion consistent with traditional strategic or master plans. The following is a suggested outline for a traffic signal management plan (TSMP).
Extract from Utah Department of Transportation Draft TSMP
The purpose of this Traffic Signal Management Plan (TSMP) is to provide a framework for delivery of high quality service to the public through an efficient and well-maintained traffic signal system. The plan describes the objectives of traffic signal management within the context of the Utah Department of Transportation (UDOT) vision, mission, strategic goals and accountability. The plan sets out strategies to guide the maintenance, design and operation of the traffic signal system. It also defines appropriate measures of performance to determine the extent to which the objectives are being met, and verification reports to confirm that the defined strategies continue to be appropriately implemented on an ongoing basis.
The executive summary provides a brief overview of what is in the document. This is a good place to list the TSMP objectives and discuss how they connect the strategies and tactics to the agency’s goals.
Chapter 1 – Introduction and Background
Include an introduction to the document and a summary of your existing traffic signal system. The purpose of this section is to provide context to your system and create a baseline for activities.
The background summary may include the following:
- Purpose of the document and the procedure used to develop it.
- Map/list of existing traffic signals.
- Map/list of existing communications infrastructure.
- Table documenting history of traffic signal updates.
- Description of existing staff organizational structure.
- Description of relationship with adjacent agencies and regional partners.
Chapter 2 – Goals and Objectives
This chapter will summarize the agency's transportation goals and the TSMP Objectives that support those goals. This chapter will describe the context within which the TSMP exists. Figure 9 illustrates the context of the City of Walnut Creek TSMP.
Figure 9. Diagram. Traffic signal management plan context diagram.
Source: City of Walnut Creek
2.1 Transportation Goals
You may choose to list all the agency goals and then highlight the ones that relate to the signal system or you can list only the ones that relate to the signal system.
2.2 Traffic Signal Management Objectives
List the consolidated Objectives that relate to the agency goals and work for both the planner and operator.
2.3 Performance Measures
Summarize the Performance Measures you use, the method you use to obtain each metric and the objective it supports.
Chapter 3 – Maintenance
This chapter documents the maintenance strategies and tactics you will use to meet the traffic signal management objectives.
3.1 Maintenance Strategies & Tactics
It is often convenient to describe three strategies for maintenance:
- Proactive maintenance strategies
- Reactive maintenance strategies
- Administrative maintenance strategies
Proactive maintenance strategies ensure that:
- Components of the traffic signal system that have a limited service life are regularly cleaned, replaced, recalibrated or tuned to prevent equipment failures;
- Information that will prevent damage by others is provided in a timely manner.
Example proactive tactics are included in Table 10.
Table 10. Example proactive maintenance tactics.
|Maintain accurate as-built records of all elements of the traffic signal system, in a form readily accessible by maintenance staff when needed.
|Visit every intersection once every two months and undertake all preventive maintenance activities, according to relevant procedure.
|Provide up to date as-built records in a timely fashion to anyone who needs them in order to prevent damage to the traffic signal system.
|Test items susceptible to damage that cannot be identified by observation during preventive maintenance activities, on a regular schedule using defined procedures.
|Assign an expected lifespan to each traffic signal element, beyond which failure rate or performance is likely to unacceptable, and plan for timely replacement.
Reactive maintenance strategies ensure efficient and effective response when equipment fails and an emergency response is required to restore operation. Example reactive maintenance tactics are included in Table 11.
Table 11. Example reactive maintenance tactics.
|Maintain a sufficient number of generators to be able to restore stop-go operating at up to three intersections at which power has been cut and will not be restored within six hours.
|Maintain sufficient spares at the maintenance facility to restore full operation of up to three intersections that experience equipment failures within 24 hours.
|Maintain sufficient spares of safety-critical equipment on each maintenance vehicle to allow restoration of safe operation at an intersection that experiences safety-critical equipment failure within two hours.
|Provide sufficient technicians on duty, on call or on contract to ensure safety-critical issues can be attended within agreed time parameters. (E.G., blacked out signal within one hour 24/7; signal timing error causing unsafe or illegal driver behavior within XX hours 24/7).
|Have contracts in place to accommodate without delay, repairs that cannot be undertaken by maintenance technicians.
Administrative strategies enable the proactive and reactive maintenance to be smoothly implemented and continued in a sustainable manner. Examples of administrative maintenance tactics are shown in Table 12.
Table 12. Example administrative maintenance tactics.
|Train all staff to be proficient in all activities to which they are assigned.
|Analyze maintenance logs and regularly report effectiveness and efficiency.
|Introduce new equipment in a cautious, structured manner with appropriate training and testing equipment.
|Provide flexibility to work non-standard hours when required to accommodate emergency and unusual maintenance circumstances.
3.2 Implementation Verification
Define the records and analysis needed to verify, through periodic assessment, the extent to which the maintenance activities have been implemented. Examples of implementation verification measures for maintenance strategies and tactics are included in Table 13. For each metric, you should include the target value to be judged satisfactory, and the frequency of measurement and reporting.
Table 13. Example maintenance implementation verification tactics.
|Maintenance Verification Metric
|Comparison of actual vs programmed activities
|Variance of zero days
|Number of reactive activities, by equipment type
|Time to respond to emergency calls
|Varies by type of reported fault
|Time to provide requested information (e.g., mark underground facilities)
|Number of staff trained to maintain equipment, by type
|Varies by type of equipment
|Time to clear failures, by type
|Varies by type of fault
|Detector status report
Tabulation of maintenance work orders
|Fix detection problems before public notices
|Report equipment and spares inventory, actual vs planned.
|Report staff status actual vs planned
Chapter 4 – Operations
This chapter documents the operations strategies and tactics you will use to meet the signal system objectives.
4.1 Operations Strategies and Tactics
List the strategies that relate to operations and briefly describe which objectives are being met by the strategies. It is often convenient to group your tactics under the following operations strategies:
- Operate the system efficiently
- Coordinate signals where this will improve traffic operation
- Time signals to provide multimodal safety and efficiency
- Use phasing and timing to operate intersections efficiently
- Operate signals in coordination with regional partners using compatible strategies
Example tactics supporting system efficiency are included in Table 14.
Table 14. Example system efficiency tactics.
|Install hardware and software to continually monitor performance under all conditions to which the operational strategies are being applied, and report the quality of that performance.
|Automatically monitor traffic conditions and review signal timing whenever conditions change beyond a pre-determined amount.
|Operate signals in a mode that suits current traffic conditions (e.g., use adaptive signal control to automatically adjust signal timing to suit the current traffic conditions; or use traffic responsive pattern selection to select the timing pattern most appropriate for the current traffic conditions).
Example tactics supporting effective signal coordination are included in Table 15.
Table 15. Example signal coordination tactics.
|When needed to accommodate demand, provide a "pipeline" along arterial roads, to maximize flow on the coordinated route while keeping side street delay to an acceptable level.
|While accommodating demand, as far as possible, coordinate signals along arterial roads to minimize stops along the arterial, while keeping side street delay to an acceptable level.
|Away from major arterials, distribute phase splits to balance delays on all approaches.
|Where protected/permissive left turns are provided, allow the protected phase to be excluded from the signal pattern when the permissive phase will provide sufficient capacity to safely accommodate all left turns without carryover queues.
|When providing coordination, include consideration of "complete street" policies.
|Review, and revise as appropriate, coordinated signal timing at least once every two years.
Example tactics supporting multimodal safety and efficiency are included in Table 16.
Table 16. Example multimodal safety and efficiency tactics.
|Provide adequate phase green and clearance times for bicycles on each traffic signal phase, using relevant Caltrans and national standards.
|Use phase clearance times and pedestrian walk and clearance times calculated to comply with CA MUTCD and other applicable standards.
|Depending on the area, optimum synchronization of vehicular traffic may be compromised to accommodate pedestrian, bicycle and transit needs.
Example tactics supporting intersection efficiency are included in Table 17.
Table 17. Example intersection efficiency tactics.
|Review signal timing at applicable traffic signals whenever a policy related to timing is modified.
|Use signal timings and flexible phasing arrangements to prevent queues exceeding critical lengths in left turn bays, in short blocks on arterial roads and on freeway off-ramps.
Example tactics supporting regional coordination and compatibility are included in Table 18.
Table 18. Example regional coordination and compatibility tactics.
|Coordinate signals across jurisdictional boundaries by: operating all signals on one system; coordinating patterns across boundaries by synchronizing clocks and timing patterns; or coordinating patterns across boundaries by interconnecting systems.
|Participate in regular operations coordination meetings with adjacent agencies.
|Coordinate arterial signals with ramp intersection signals.
|Coordinate arterial signals with ramp meters.
|Coordinate signals to accommodate traffic diverted by freeway incidents.
4.2 Implementation Verification
Define the records and analysis needed to verify, through periodic assessment, the extent to which the operations activities have been implemented. Examples of implementation verification measures for operations strategies and tactics are included in Table 19. For each metric, you should include the target value to be judged satisfactory, and the frequency of measurement and reporting.
Table 19. Example operations implementation verification metrics.
|Operations Verification Metric
|Arterial volume (Throughput)
|Minor phase max-out
|Number of stops, weighted by volume
|# stops per mile
|Periodic floating car
|Frequency queue exceeds limit
|No. intersections with bicycle timing
Chapter 5 – Design
This chapter documents the design strategies (or standards) you will use to meet the operational objectives. This section links how design standards impact maintenance and operations resources. It will also show how design elements need to be driven by the operations strategies (e.g., detection in the right place, correct type of detection, use of suitable signal phasing, control of variety of equipment).
5.1 Design Strategies and Tactics
List the strategies that relate to design and briefly describe which objectives are being met by the strategies. It is often convenient to group your tactics under the following design strategies:
- Operations support.
- Maintenance support.
- Multimodal accommodation.
- Regional coordination.
- Manage design process efficiently.
Example tactics supporting operations are included in Table 20.
Table 20. Example operations support tactics.
|Design signals to allow application of versatile operational strategies to suit varying traffic conditions and changing community expectations (include relevant details).
|Specify detection systems that have a proven record of high performance and reliability, and are maintainable at a high level of availability (include relevant details).
|Design a communications system to have a high performance level in terms of capacity (bandwidth), communication speed, reliability and availability, suitable to accommodate all operational requirements.
|Design system to allow efficient setup, fine tuning and monitoring by operations staff.
|Provide high standard communications from the TOC to every City-operated traffic signal.
|Use non-invasive detection technology on approaches requiring high street maintenance or underground utility activity that would damage normal loops.
|Use robust detection installation that will be less affected by pavement deterioration, road maintenance or construction activities.
Example tactics supporting maintenance are included in Table 21.
Table 21. Example maintenance support tactics.
|Design the traffic signal system to allow a high level of efficiency and cost-effectiveness of maintenance and operation activities (reference design standards).
|Design system to automatically detect and report faults.
|Design system to minimize failure rates of equipment units.
|Design signals to minimize risk of damage due to crashes and vandalism.
|Design system to allow fast and efficient response by maintenance staff.
|Design communications system to self-diagnose and report faults.
|Design communications system to be self-healing.
|Design communications system to minimize damage by others.
|Design communications to have low risk of damage by others.
Example tactics supporting multimodal accommodation are included in Table 22.
Table 22. Example multimodal accommodation tactics.
|Provide a high level of accessibility of traffic signals to all road users (e.g., facilities accommodating pedestrians, cyclists, transit passengers).
|Provide crosswalks for all reasonable pedestrian movements at traffic signals.
|Provide push buttons for all pedestrian phases.
|Provide bicycle detection in each bicycle lane at each traffic signal.
|Provide bicycle detection in each traffic lane at each traffic signal.
|Upgrade intersection elements to current ADA standards when significant modifications or construction work are undertaken in the vicinity of the intersection. (Need to have a policy defining what is significant, and what thresholds will be used to determine what work is appropriate.)
Example tactics supporting regional coordination and compatibility are included in Table 23.
Table 23. Example regional coordination and compatibility tactics.
|Interconnect signals across jurisdiction boundaries.
|Design arterial signals to coordinate with ramp intersection signals.
|Design arterial signals to coordinate with ramp meters.
Example tactics supporting efficient design management are included in Table 24.
Table 24. Example design management tactics.
|Follow systems engineering principles for all new system elements and when considering major changes to the system (Describe approach in an appendix; List suitable references and guidebooks, such as FHWA's guidance documents and standards).
|Maintain a design review checklist to identify all elements that must be included in a design and the appropriate standard or specification.
|Design system to share high bandwidth communications with other departments and agencies where it will be feasible and cost-effective.
|Specify materials to minimize deterioration of performance and appearance that would require continued maintenance or early replacement.
|Routinely review existing traffic signal installations to ensure their design is still appropriate for the prevailing conditions (e.g., appropriate number of phases, appropriately accommodate pedestrians and bicycles, the need for the signal is still valid).
5.2 Implementation Verification
Define the records and analysis needed to verify, through periodic assessment, the extent to which the operations activities have been implemented. Examples of implementation verification measures for design strategies and tactics are included in Table 25. For each metric, you should include the target value to be judged satisfactory, and the frequency of measurement and reporting.
Table 25. Example operations implementation verification metrics.
|Operations Verification Metric
|Document number of signals with full vehicle-actuated capability.
|Document number of signals with full communications capability.
|Document reliability of detection, by type.
|Annual failure rate, by type
|Document actual vs planned communications bandwidth, by intersection.
|Actual = Planned
|Document number of detectors not operating as designed, and reason for failure.
|95% serviceable at any one time
|Document resources required for setup, fine tuning and monitoring activities.
|Confirm specifications consistent with needs of all operations and maintenance.
|Document faults found during maintenance are consistent with reports and alarms generated by system.
|System reports 100% of faults
|Confirm all required details are in design review checklist.
|Report design exceptions, variations from standards and design review checklist.
Chapter 6 – Management and Administration
This chapter documents the strategies and tactics that are associated with enabling activities (management, administration and customer service). These strategies relate to the management of the staff, personnel issues, programming and budgeting, not the day to day activities on the street.
6.1 Management and Administration Strategies
List the strategies that relate to management and administration and briefly describe which objectives are being met by the strategies. It is often convenient to group your tactics under the following management and administration strategies:
- Inter-department coordination
- Budgeting and programming
- Customer service
Example tactics supporting personnel strategies are included in Table 26.
Table 26. Example personnel tactics.
|Provide a well-trained group of staff with sufficient resources to handle staff changes and temporary fluctuations without compromising the performance of the traffic signal system.
|Coordinate the activities of all relevant staff involved in planning, designing, operating and maintaining the traffic signal system.
|Develop and implement a succession plan for each staff position.
|Document procedures to the extent necessary for a new or temporarily assigned staff member to be able to efficiently complete the duties of the position.
|Define qualifications appropriate for all staff and a policy to ensure staff remain appropriately qualified.
Example tactics supporting inter-departmental coordination are included in Table 27.
Table 27. Example interdepartmental doordination tactics.
|Define when and how to coordinate planning reviews with operations and maintenance staff.
|Define when and how to coordinate CIP development, grant applications and internal budgeting.
|Define how to handle design reviews.
Example tactics supporting budgeting and programming are included in Table 28.
Table 28. Example budgeting and programming tactics.
|Maintain a list of intersections that require upgrade or improvement when modifications are proposed by others (e.g., developer of adjacent property). (List should be based on regular assessment of intersection operations, maintenance history, obsolete or defective equipment, within an undergrounding district, listed in the CIP, etc.).
|Maintain a plan to avoid obsolescence as current equipment ceases to be supported by vendors.
|Regularly review new technology developments beyond traffic signals that will require modifications to existing equipment and practices (e.g., connected vehicles).
Example tactics supporting customer service are included in Table 29.
Table 29. Example customer service tactics.
|Empower all employees to be ambassadors of the City by providing them with a good understanding of the traffic signal system, and training them to recognize when it is appropriate to discuss with customers and when to refer to a more qualified staff member.
|Measure and report our performance in responding to complaints.
|Tell customers ahead of time what to expect (e.g., normal operations, planned events such as community events and lane closures, and expected incidents such as weather events).
|Provide timely information in response to unplanned and unexpected incidents and emergencies.
|Report regularly to officials, show where the traffic signal management plan is leading and how it is responding to the City’s goals and objectives.
|Engender pride in the traffic signal system.
Provide procedures and standards to all staff for customer service activities, such as:
- Accepting and responding to trouble calls.
- Accepting and responding to requests to modify the way the traffic signal system is designed or operates.
- Dealing with media requests.
- Reporting system performance to City Council.
6.2 Implementation Verification
Define the records and analysis needed to verify, through periodic assessment, the extent to which the management and administration activities have been implemented. Examples of implementation verification measures for management and administration strategies and tactics are included in Table 30. For each metric, you should include the target value to be judged satisfactory, and the frequency of measurement and reporting.
Table 30. Example management and administration implementation verification metrics.
|Management Verification Metric
|Time to respond to customer
|Initial response – X days
|Time to close out request
|Closeout – two weeks
|Types of inquiries
|Percentage of inquiries satisfied
Chapter 7 – Interagency Communication & Collaboration
This chapter documents the existing relationship between your agency and adjacent agencies that may have influence on the transportation system. Discuss how you communicate and collaborate on operational issues and planning for future projects. Document where your operational objectives do not align perfectly with your neighboring agencies, particularly where your operations interface such as at jurisdiction boundaries, at freeway interchanges and where arterial roads pass through shopping and business districts. Examples of non-alignment of operational objectives include:
- A regional agency wanting to maximize throughput on arterials during peak hours, but a local agency wanting to provide smooth flow at that time.
- A highway agency using ramp metering to protect freeway flow, which causes queuing that, interferes with arterial operation.
- A transit agency wishing to have higher performance through use of signal priority, while a local or highway agency regards overall traffic efficiency as paramount.
Strategies will typically fall into the following categories:
- Staff from partner agencies with similar responsibilities regularly meet, maintaining a forum for discussing traffic signal system issues of mutual interest (such as planning, design, operations and maintenance).
- Partner agencies cooperate to present a unified program or complementary projects when seeking funding.
- Maintain cooperative agreements for important issues such as system design and compatibility, and supportive maintenance arrangements.
Chapter 8 - Action Plan
This chapter documents a framework to help you identify areas of improvement, better organize your work plan, and secure funding and other support. Document where you are today and where you want to be in the future. You then can create an action plan on how to get from one point to the other.
The key elements of the action plan should be:
- Document procedures and activities that are currently performed on an ad hoc basis. Capture for posterity the good practices currently performed by staff who have developed their practices through experience and in response to the constraints under which they work, but have not written them down. This will be important for sustainability of your operations in the face of staff turnover and resource limitations.
- Define how you will measure both what you do (your outputs) and what you achieve in the eyes of the community (your outcomes). Use this section to plan what resources you need and systems that must be in place to make those measurements.
- Define how you will use the results of your measurements to review and revise your operations in order to optimize your activities, to provide the outputs most efficiently and achieve the best outcomes possible within your resource limitations.
This chapter also documents events or circumstances that can trigger review and revision of the TSMP, and define a process to control how updates are developed and implemented, in a manner that will not be counterproductive.
An example action plan is illustrated in Table 31.
Table 31. Sample traffic signal management plan action plan.
|Prepare a list of procedures that are applicable to the signal management tactics; consolidate into an appendix to this document or (if they existing in other manuals of procedures) specify their storage location in the list.
|Three months after adoption
|Prepare procedures for activities that are not adequately described in existing procedures.
(List the procedures that are not currently documented, or for which the documentation is dispersed and needs to be consolidated).
|Twelve months after adoption
|Prepare staff training, backup and transition plan for each position
|Six months after adoption
|Introduce the traffic signal management plan the entire design, maintenance and operations team
|One month after adoption
|Develop a quarterly assessment and action plan
|Prepare an assessment of the impact of Vehicle to Vehicle (V2V) and Vehicle to Infrastructure (V2I) developments on traffic signal management.
|Six months after adoption
|Schedule a refresh of the document in one year's time
|Twelve months after adoption