1.1 Introduction

Traffic Management Centers (TMC) collect and combine real-time transportation information with other operational and control data to effectively manage and monitor the transportation network and provide traveler information. This is accomplished by using advanced technology, reliable communication infrastructures, efficient signal control, and traveler information dissemination systems. To maintain effective and reliable TMC operations, it is vital to equip a TMC with state-of-the-art technology for its traffic signal system, ITS components and communications infrastructure.

The Minneapolis TMC, located at 300 Border Ave, Minneapolis, Minnesota, is responsible for operating all traffic signals and monitoring and managing daily traffic operations in downtown Minneapolis and surrounding areas within the City limits. However, several factors limit the existing TMC’s ability to provide efficient and flexible signal control and traffic operations that meet the growing traffic demand and increasing needs of traffic safety and homeland security. First, twenty percent of the existing traffic controllers are electromechanical traffic signal controllers and are obsolete in technology. Second, the current TMC central control equipment is at the end of its useful service life and replacement parts are becoming increasingly difficult to purchase because the manufacturers no longer support this equipment. Third, the existing twisted-pair communication cables may not be able to support upgraded TMC’s capabilities due to its limited transmission rates and distance. Finally, the existing centrally-controlled system requires constant second-by-second communications to the field devices which eliminate TMC’s expectation to develop redundant control capability for future security and reliability purposes.

In order to meet the future TMC needs, the City of Minneapolis applied for and was awarded several Congestion Mitigation and Air Quality (CMAQ) grants. These grant-awards are authorized by the transportation bill, Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) and will be used to upgrade the City’s TMC traffic signal and control systems and enhance the City’s ITS capabilities. The upgrade and enhancements will not only improve the efficiency and functionality for the TMC but also strengthen the coordination and partnership with neighboring cities and stakeholders in establishing a regional traffic operations and management framework.

The Minneapolis TMC upgrades are planned to be accomplished in three separate phases based on the available funding. Phase one will include upgrading TMC computer system and communications infrastructure using 2009 and 2010 funding. Phase two will include replacing existing electromechanical traffic signal controllers with state-of-the-art traffic signal controllers using 2011 and 2012 funding. Phase three, currently unfunded, will include deploying ITS devices such as Dynamic Messages Signs (DMS), surveillance cameras and other ITS systems. According to City’s needs and priority of interest, the initial effort will focus on the first two phases. Phase three will be implemented based on future funding availability.

As required by Federal Highway Administration, the City of Minneapolis is following the systems engineering process to develop the Concept of Operations which is the initial step that will lead to future system requirements development and system design. The Concept of Operations defines a high-level description of what the major capabilities will be for the upgraded TMC/ITS system and present high-level operational concepts from a user’s vantage point. The proposed concept explains how things are expected to work once the upgraded TMC is in operation, and identifies the responsibilities of the various stakeholders for making this happen.

This Concept of Operations is the result of stakeholder interviews and meetings on how the upgraded TMC will improve traffic operations within the City and neighboring jurisdictions under normal and emergency conditions. It is intended that this document will be used as a reference in upgrading the Minneapolis TMC and may be modified as determined necessary.

1.2 Project Vision, Goals and Objectives

1.2.2 Project Goals and Objectives

The goals and objectives of this document are to identify operational characteristics for the upgraded TMC, document user needs, and provide justification for, and expectations of, the proposed TMC systems. The goals and specific objectives for the Minneapolis TMC upgrade are defined as follows:

Goal #1: Improve TMC Operations. The Minneapolis TMC will upgrade its signal controllers and control systems to improve TMC operational efficiency.

Objective 1-1: To replace electromechanical signal controllers with state-of-the-art Controllers

Objective 1-2: To upgrade the TMC computer system with state-of-the-art technology

Objective 1-3: To upgrade the TMC system control software to improve TMC operational capability

Objective 1-4: To develop a multifunctional TMC control center to effectively control traffic signals and ITS devices and facilitate traffic information exchange and traveler information dissemination

Objective 1-5: To improve communications infrastructure through implementation of Internet-Protocol (IP) based communications to ensure communication capacity and security

Objective 1-6: To develop a system that allows for remote access and control of signal system and ITS devices

Objective 1-7: To improve system capability in data collection and archiving and provide available information for system performance measurements and monitoring

Objective 1-8: To implement a traffic control system with limited dependence on central control Objective 1-9: To increase staffing levels to meet project goals

 

Goal #2: Improve TMC Scalability. The City of Minneapolis will procure and deploy an upgraded traffic signal and TMC control system that will allow for future expansion or upgrades.

Objective 2-1: To deploy a system with an open architecture for future expansion and upgrades Objective 2-2: To adopt national standards as appropriate for future expansion and upgrades

Goal #3: Improve TMC Interoperability. The Minneapolis TMC will work with partnering stakeholders to improve signal coordination, information exchange and traveler information dissemination.

Objective 3-1: To develop a close partnership with neighboring cities and related Stakeholders

Objective 3-2: To develop and implement signal progression on bordering roadways

Objective 3-3: To improve system integration, coordination and information exchange with partnering agencies

Objective 3-4: To improve system integration, coordination and information exchange with future ICM system

Goal #4: Improve Traffic Mobility and Reliability. The City of Minneapolis will procure and deploy a state-of-the-art signal system to enhance mobility and reliability of travel within the City limits.

Objective 4-1: To facilitate traffic signal timing optimization and coordination

Objective 4-2: To effectively implement traffic responsive strategies

 

3.1.1 TMC Control Center

Room Arrangement

The current Minneapolis TMC control center, located at 300 Border Avenue, Minneapolis, includes a computer room, an electronics room and a small storage room. The computer room hosts consoles, central control workstations, a static Light-Emitted-Display (LED) based wall map, and operators’ desks. The adjoining room houses the air-conditioning systems, telephone, and signal system cable termination facilities. The electronics room is used for storage and maintenance of traffic signal electronics and communications equipment. The storage room includes shelves and coat rack for storing miscellaneous personal items. See the Figure 3.1 for the current TMC floor plan.

Computer System

The Minneapolis TMC centrally controls and operates 750 signalized intersections in Minneapolis. The control system consists of a FORTRAN T2000C signal control system supported by a VAX computer, FASTRACS control software, a static LED monitor wall, Diamond video switcher with multiple display monitors, and an Autoscope video management system.

The VAX computer supported T2000C system is a multi-user, multi-tasking, and real time signal control system. The system supports second-by-second communications, and selects signal timing plans based on either time-scheduled operations or traffic-responsive values. The traffic responsive operations are based on the criteria derived by the volume and occupancy data collected from field detectors and user-defined parameters.

Central Software

The T2000C control software, in conjunction with the FASTRACS user interface software, performs second-by-second control of each intersection or functions as a distributed control system with second-by-second monitoring capability. It is compatible with the existing population of field equipment and able to control and monitor traffic signal controllers and other attached equipment via City-owned twisted-pair copper communication links.

The T2000C/FASTRACS system also monitors and controls 17 intersections along the Hiawatha LRT corridor utilizing NTCIP communications. The current Minneapolis TMC also includes the SCOOT system as a stand-alone module resident on the VAX computer linked to and integrated with the T2000C control system through an Ethernet link. Currently, the SCOOT system is not in operation.

Traffic Signal Controllers

The field devices monitored and controlled from the Minneapolis TMC include traffic signal controllers and cameras. The Minneapolis TMC has deployed and is operating several different types of traffic signal controllers City-wide. These controllers include 607 Eagle/Siemens EPAC series, 178 Eagle EF 20 Electromechanical controllers, 8 Eagle EPIC controllers, 5 Honeywell 190 and 4 Honeywell 40 controllers with external coordinators. Approximately 300 signalized intersections are on County roadways and 150 signals are on Trunk highways.

Cameras

A total of nine pan/tilt/zoom surveillance cameras have been deployed in the City to provide the TMC with real-time traffic monitoring. In addition, a total of 135 Autoscope Solo video sensors installed at 56 intersections in downtown Minneapolis area are used as fixed position surveillance cameras by the TMC.

DMS

It is expected that DMSs will be deployed to control and disseminate traveler information to the public. Currently, these signs provide parking guidance and availability information and are manually controlled by Parking Operations staff from the Hawthorne Transportation Center. A total of 15 DMSs located on city streets within the central business district (CBD) area are mounted on signal standards around the Minneapolis Convention Center to provide parking information.

5.1 Daily Motorists’ View

Daily motorists should experience effective traffic signal timings and coordination and be able to make informed en-route commute decisions when driving in the Minneapolis’s CBD and other areas within the City limits. Optimal signal timing plans should be developed and implemented to minimize delay and stops and maintain safe and efficient traffic mobility along local streets and arterials for daily peak and off-peak traffic.

Special event signal plans should be developed to accommodate inbound and outbound traffic flows at various events (e.g. Viking, Twins, Timberwolves games, concerts, and conventions), tourist attractions and planned detours for both weekdays and weekends. Real-time traveler information describing traffic conditions, travel times and parking information for various modes and routes should be provided via radio, dynamic and static message signs to help motorists understand their options on where to park and how to get in and out of downtown from and to freeway entrances and major arterials.

The upgraded TMC should effectively provide incident and planned event and construction information to the public including location, severity, duration, expected delay and detour routes. The TMC should assist the Police Traffic Control staff to guide and manage traffic under severe or significant congestion conditions.

In general, through signal coordination and traveler information dissemination via various media outlets, motorists should expect to experience the benefits of efficient travel time, fuel saving, emission reduction, less surprises en-route, less stress and ultimately, safer travel for the daily commute.

5.2 Minneapolis TMC Operators’ View

The upgraded Minneapolis TMC must provide efficient and flexible traffic management capabilities for daily peak periods, planned events, and emergencies in the City of Minneapolis. The upgraded TMC computer system must have an open architecture to accommodate various traffic signal controllers that are compliant with NTCIP standards and other proprietary communication protocols. TMC operators and authorized users outside the TMC must be able to remotely access signal controllers and signal controller databases, select signal timing plans from a database as appropriate and upload the signal plans to the controllers from the TMC or from a remote location via wireless link. The upgraded TMC must be able to support all signalized intersections within the City limits with significant room for future expansion.

The TMC operators must have the capability to implement pre-timed, coordinated, time-of-day, and traffic-responsive signal plans for isolated intersections, arterials, and network control and select special signal plans that assist onsite traffic control staff in performing manual traffic management during congested periods. The upgraded system should support the TMC operators’ ability to effectively coordinate with different jurisdictions and other internal partnering agencies (Fire, Police, EOC/SIC, Parking Services, and Public Affairs) and enable quick responses to incidents, emergencies and potential evacuations.

The upgraded TMC must have the capability to share its surveillance cameras with other partnering agencies and be able to access Mn/DOT’s and other agencies’ cameras to allow the TMC operators to monitor real-time traffic for freeways, arterials and local streets.

The upgraded TMC must have the capability to collect, store and archive real-time volume, speed and occupancy data for monitoring and assessing traffic conditions, TMC system performance, as well as other operational and research needs. The traffic data should be made available via download to other jurisdictions such as the University, Metro Transit, and other authorized stakeholders, as needed.

The upgraded TMC shall have the capability to detect and have its operators to be alerted of an incident automatically. This would allow the TMC operators to focus their attention on the incident location and monitor traffic impacts by observing traffic data and viewing cameras. Additionally, the control system shall automatically send the information to a group of pre-determined stakeholders and disseminate incident reports, construction projects, any planned events and lane closures to the public directly or indirectly via 311 and 511 telephone systems, KBEM (88.5 FM), or through other public and private information service providers.

Transit Signal Priority (TSP) systems will be deployed by Metro Transit and the Minneapolis TMC to improve transit schedule adherence and reliability through the UPA Transit Technology project at selected intersections along Central Avenue in Minneapolis. The TMC operators must be able to remotely monitor TSP operations after the system is fully operational, and have the authority to control (enable and disable) the TSP operations as needed by coordinating with Metro Transit.

Additionally, it is anticipated that the upgraded TMC must be able to accommodate redundant operations with other agencies for an emergency. The upgraded TMC should be designed to have the ability to operate, upon request, additional traffic signals and ITS devices owned by other agencies outside the City as long as these devices are compatible with the future TMC control system.

On the other hand, the future TMC should have the ability to support redundant control from a remote location. This will allow a selected agency to remotely operate TMC control systems and ITS devices during an emergency or any other TMC defined circumstances.

Minneapolis Police

Traffic Control and Traffic Enforcement units under Minneapolis Police guide and manage the traffic and should continue to be assisted by the upgraded TMC operators for daily peak traffic periods and special events. Additionally, Friday night and Saturday night are two challenging periods for Police Traffic Control and Enforcement units to perform traffic management in downtown Minneapolis. The traffic control supervisor should be able to remotely access the upgraded TMC and implement special signal plan(s) as needed. The Police should be able to communicate with the upgraded TMC via e-mail, phone or 800 MHz radio phone system using a predetermined phone tag when an incident or an emergency occurs.

When the Police Department is notified to assist a motorcade passing through downtown area along a predetermined route, a special coordinated signal plan should be able to be activated to facilitate movement of the Motorcade as it passes signalized intersections along the route without stopping. The signal coordination could allow the Police Department to save significant manpower by eliminating the number of Police personnel needed at each intersection along the motorcade route.

The Police Department is developing a special downtown evacuation plan based on emergency management and the Metro Evacuation Traffic Management Plan. The upgraded TMC should take the future downtown evacuation plan into consideration and coordinate with the Police Department in developing special signal plans that can be used to facilitate potential evacuation events.

Minneapolis EOC/SIC

The upgraded TMC should establish a direct link and provide instant incident notification to the EOC/SIC which will be constructed near the Minneapolis water treatment facility located in Fridley, Minnesota. The information will help the EOC/SIC operators to assess traffic conditions and monitor any emergency situations for emergency management purposes. The upgraded TMC should be integrated with all local 911 systems to effectively distribute incident and emergency information to the EOC/SIC and other related agencies without delay.

The EOC/SIC anticipates accessing the upgraded TMC surveillance cameras to monitor real-time traffic and incident conditions in downtown. The upgraded TMC should include the development of a video repository to support regional video sharing for all agencies that are willing to share video with each other.

Minneapolis BIS/GIS

The Minneapolis Business Information Services (BIS) should provide information technology (IT) support for the TMC upgrades. Optimal IT solutions should be determined to help develop reliable and secured communication network interfacing with outside networks to ensure efficient information flow with other agencies.

Personnel involved directly with GIS administration in the City should be able to receive and incorporate real-time traffic data into a GIS database for City and public uses. The GIS Department could integrate the real-time volume, speed, lane closure and other useful traffic data provided by the TMC into an enterprise GIS database to provide GIS-featured map services and make them available to the public. The interactive GIS map could serve as a tool for the public to check real-time traffic conditions and make informed decisions as needed.

6.1 Justification for Change

The Minneapolis TMC has been using a computer system to operate multiple traffic signal controllers made by different manufacturers over the twisted-pair communication cables for more than 30 years. Currently, the TMC central control equipment is at the end of its useful service life. The existing equipment is no longer supported by the manufacturers and replacement parts are increasingly difficult to purchase. With much of the City’s traffic signal control field equipment having been upgraded to current state-ofthe-art hardware, the need to be able to control electromechanical and externally coordinated equipment is being eliminated. Since the existing traffic control system limits the efficiency, interoperability, and expandability of the TMC and creates concerns for system reliability, it is vital for the Minneapolis TMC to upgrade its remaining electromechanical traffic signal controllers and the central control system to current technology.

Additionally, growing traffic demands in downtown Minneapolis and neighboring jurisdictional areas require the Minneapolis TMC to be more efficient and flexible in traffic operations. A new traffic control system that allows for remote access, decentralized control and quick responses is essential to accommodate varied and increasing traffic demands in the City of Minneapolis. The need for traffic safety, emergency management and homeland security requires better coordination among the Minneapolis TMC, Mn/DOT, and other designated stakeholders and neighboring jurisdictions. Improved coordination will allow all stakeholders to improve traffic operations, traffic signal coordination, and information exchange. Enhancements will make the overall TMC/ITS components function better and provide additional benefits to the City and related partners.

6.2 Description of the Proposed System Needs

Room Arrangement

The upgraded TMC control center will be constructed structurally and functionally to better serve system operations, management, administration, maintenance, training and demonstration needs. The control center redesign will include a control room, a conference room, office spaces, and an equipment room. Figure 6.1 shows the concept for a future upgraded TMC floor plan.

The existing Computer Room shown previously in Figure 3.1 will be used as the Control Room and remodeled to host new consoles, computer and communication systems, and a multi-screen video wall system. If budget allows, a table projection system will also be installed. The curtain wall between the current Computer Room and the block wall between the Computer Room and the Electronics Room will be removed to make a large space available for the installation of the new control system, cabling, and other components. The Control Room will be designed to create a secure and quiet environment for system operations.

The Conference Room will be used to facilitate meetings regarding system operations, traffic management, administration and research. A window between the Conference Room and Control Room will allow TMC operators to demonstrate system operations and promote future TMC’s capabilities and benefits when there is a visitation from other stakeholders or agencies without distracting system operators.

A total of six office rooms are proposed to provide supervisors and operators with spaces to conduct daily management and administrative tasks.

An equipment room is proposed for storing computer and communication equipment, terminal facilities, operational materials, phone, traffic signal cabling and other necessary equipment.

The potential remodeling efforts will include rearranging existing walls, raising the ceiling, and lowering the floor. The mechanical work may include replacing the existing HV/AC air conditioning system to better accommodate the operators and equipment inside the control center. Final room arrangement will be determined and designed in the future design phase.

Consoles

Workstation consoles are a required part of the TMC enhancements. The new control console will be able to accommodate three operators for daily operations or facilitate a trainer, trainee and a guest for training or demonstration purpose. These consoles will include workstations and monitors to perform daily monitoring functions of the various systems deployed at the TMC and include work surfaces that can change heights and house various computer components.

Display Wall

A multi-screen display wall system is desired that will include two regular and one backup ceiling-mounted LCD projectors and a wide wall screen with advanced computer technology and special video cards. The images displayed on the wall are not only standard video but also computer generated information and non-standard video formats. The system will provide high resolution display that allows imaging from multiple sources to be simultaneously and flexibly displayed on the wall screen. The wall content can be controlled interactively and any standard Microsoft Windows applications can be controlled and displayed by the operators. This facility will allow the TMC operators to monitor the signal performance and real-time traffic on the wall screen at the same time and provide a platform for training and system demonstration.

The same technology can be used for a table projection system. The difference is to project the interactive PC-based applications to a table instead of a wall. This will provide another useful interactive tool for the engineering staff to plan, develop and analyze traffic operations and management on a horizontal platform.

Computer System

The upgraded TMC will integrate the entire traffic signal system (controller, conflict monitor, emergency vehicle preemption, video detection) and ITS devices (cameras, DMS, and lane use control signals) into one network to monitor device performance and for data collection and troubleshooting. The new system shall need to provide sufficient process speed, capacity, and expandability. It is anticipated that the upgraded TMC computer system will have the capability to support up to 3000 traffic signals in addition to other ITS devices.

The system architecture for consideration would employ a distributed client/server interconnection to accommodate current needs and future expansion. Client workstations access networked computers that perform traffic management, database management, real-time communications and traffic control functions. The system should be implemented using standard, commercially available PC-based hardware for client workstations and servers.

Central system server(s) will integrate traffic signals, DMS, cameras, and other subsystems. Ethernet switches will be used to form the basis of all communications, both within the TMC, to the field hardware (existing and new/upgraded) and with other centers/agencies. An operator workstation would provide system status and control and shall be able to alarm TMC operators on screen or printers of abnormal system or device performance. Additional servers would be added as necessary if more components (intersections and ITS devices) need to be added. The computer system shall have a redundant server, a central backup and undisrupted power unit (UPS).

Laptop computers shall be provided as remote operator interfaces and for field maintenance activities. Remote Virtual Private Network (VPN) based access should be provided via remote access servers (RAS), the internet and/or routers to the City’s TMC LAN.

Control Software

The control software shall allow the TMC operators to create, store, compare and edit signal controller databases from designated workstations. It shall also provide the capability for the TMC operators to remotely access the signal controllers using IP protocols and upload and download signal timing plans selected from the database. The remote uploads and downloads shall be able to be accomplished either manually or automatically by the time of day. The TMC operators and system administrators shall be able to monitor signal performance and identify faulty signals or communications problems by receiving alerts generated by the system.

The central control software should have additional loosely integrated packages or modules for additional traffic management functions to support TMC operators managing surveillance cameras, operating DMS messages, monitoring and accessing conflict monitors, video detectors, and EVP equipment, and utilizing traffic detection devices.

The new software shall be provided and integrated for control of all devices over Ethernet connections and should be able to communicate with field devices via any media (twisted-pair copper, Wi-Fi, telephone dial-up, radio, cellular, fiber optic) that will support Ethernet communications. The system should also be capable of supporting multiple communication rates and media within the same system (IEEE 802.3z, 802.3ab,etc.)

The new central software shall allow TMC managers to configure different levels of access privileges to various authorized user classes. Remote operator interfaces from other centers/agencies, such as Mn/DOT, Hennepin County, Metro Transit Control Center, etc., shall be able to be accommodated as needed. The central software system shall be able to alarm TMC operators on screen or printers of abnormal system or device performance.

Signal Timing Plans

The upgraded TMC will continue to use existing timing plans and develop new signal timing plans to keep all signals up to date and best serve the traffic needs. Regular updates will be required to accommodate the changes in traffic volumes and patterns due

Cameras

Additional pan/tilt/zoom surveillance cameras will be deployed and integrated with the existing cameras to enhance the upgraded TMC traffic monitoring capabilities. These new cameras will allow the TMC operators to “be” in many locations at once, quickly implement signal timing revisions in response to incidents, and provide other vital information for traffic management decisions.

The number of cameras to be added to the existing City of Minneapolis system will be determined in the design phase. Since many other agencies already have cameras at important locations and the current TMC already has the ability to view Mn/DOT cameras, a study will be performed to determine the areas of the arterial system that are currently not under any surveillance and have roads that should be remotely managed. The expansion of the video images available to the City of Minneapolis does not require Minneapolis to add poles and cameras across the city. The upgraded TMC will be designed to allow the City to participate in a regional traffic surveillance network and share its cameras with partnering agencies and should have the capability to place CCTV camera images on websites.

DMS

Additional DMS signs may be deployed at key locations in downtown area and other arterials roadways in the future to support dissemination of traffic condition and traveler information. The selection of DMS locations will consider traffic volume, patterns, critical routes and decision points in the transportation network. In the future, the Minneapolis TMC could use the DMSs to provide travelers with incident information, travel time, amber alert messages and other useful travel-related information. The information could help guide and manage traffic during incidents and other emergency events.

Incident information including type, location, severity, and duration could alert drivers to expected delays on arterials or freeways and help them make informed decisions on whether it is necessary to take alternate routes. Through coordinating with the Mn/DOT RTMC, the upgraded TMC could alert drivers in the downtown area to freeway incidents before they arrive at the freeway entrance ramps.

Accurate travel time along certain corridors could be a useful piece of information to many drivers. The travel time can be collected or calculated by using several different methods including Cell Phones as Probes and Vehicle Infrastructure Integration (VII) applications. Since many cell phones have global positioning system (GPS) capabilities built into them, it gives the phone’s precise location and can accurately track the changes in position over time or average speed. This can be used to track how long it takes on average for vehicles to travel between two distinct locations.

Amber alerts and other safety information could be posted on the DMS to improve community safety and homeland security. The upgraded TMC would share the DMS messages with partnering stakeholders to improve coordination for regional safety and

Central Corridor LRT line and more cameras and DMSs that are anticipated for traffic management in the future. Currently, no inter-agency signal coordination exists between the City of Minneapolis and City of St. Paul. However, fiber-optic cables will be installed along the Central Corridor LRT line which could provide an

fashion that ensures reliability and accommodates future expansion. The Minneapolis Business Information Services will ensure system security via firewall software and hardware to the outside world.

8.1 Room Arrangement

The City will need to identify and define requirements for a temporary control room when the TMC remodeling takes place. The temporary control room should accommodate the existing workstations and computer facilities and allow the TMC operators to perform their normal functions during the transition periods. The transition of workstation and associated equipment must have minimum impact or disruption to the system and traffic signal operations.

8.2 Signal Operations

Replacing old electromechanical traffic signal controllers during the TMC upgrade will potentially result in disruptions to traffic signal operations. However, this impact can be minimized by dividing traffic signal controller replacements into several phases. Each phase will replace signal controllers for a group of signalized intersections that are currently and will continue to be coordinated along selected arterials or streets. A work plan should be developed to define these signal upgrade phases including routes, priority and sequence based on current traffic signal coordination, communication links and interfaces.

8.3 Communications Upgrade

Upgrading existing communications infrastructure to new protocols will potentially result in disruptions to traffic signal operations. The City will need to review and document existing communication facilities including signal controller interconnection diagrams, communication maps, network diagrams, and other related reference documents. The City will also need to perform field communication tests between the TMC and selected key locations. Research should be conducted on current state-of-the-art communications technology available for computerized traffic signal systems, TMC and ITS management systems. Based on the review and testing results, the City will need to define acceptable implementation strategies for staging communications upgrade in order to minimize system down time and traffic signal operations disruptions due to communications migration.

Appendix A: Public Works Business Processes for Traffic and Parking