District of Columbia ITS Architecture

DDOT TMC - Traffic Management Functionality

Subsystem Description

The Traffic Management Subsystem monitors and controls traffic and the road network. It represents centers that manage a broad range of transportation facilities including freeway systems, rural and suburban highway systems, and urban and suburban traffic control systems. This subsystem communicates with the Roadway Subsystem to monitor and manage traffic flow and monitor the condition of the roadway, surrounding environmental conditions, and field equipment status. This subsystem coordinates with the Maintenance and Construction Management Subsystem to maintain the road network and coordinate and adapt to maintenance activities, closures, and detours. Incidents are detected, verified, and incident information is provided to allied agencies, drivers (through Roadway Subsystem highway advisory radio and dynamic message signs), and information service providers. This subsystem also manages traffic and transportation resources to support allied agencies in responding to, and recovering from, incidents ranging from minor traffic incidents through major disasters. When required, special traffic management strategies are implemented to support evacuation and reentry. The Traffic Management Subsystem supports HOV lane management and coordination, road pricing, and other demand management policies that can alleviate congestion and influence mode selection. It also manages reversible lane facilities and barrier and safeguard systems that control access to transportation infrastructure. The subsystem communicates with other Traffic Management Subsystems to coordinate traffic information and control strategies in neighboring jurisdictions. It also coordinates with rail operations to support safer and more efficient highway traffic management at highway-rail intersections. Finally, the Traffic Management Subsystem provides the capabilities to exercise control over those devices utilized for automated highway system (AHS) traffic and vehicle control.

Functional Area: Collect Traffic Surveillance

Management of traffic sensors and surveillance (CCTV) equipment, collection of current traffic conditions, and distribution of the collected information to other centers and operators.

Functional Area: HRI Traffic Management

Remotely monitor and control highway-rail intersection (HRI) equipment, includes standard speed active warning systems and high speed systems which provide additional information on approaching trains and detect and report on obstructions in the HRI.

Functional Area: Rail Operations Coordination

Coordination between rail operations and traffic management centers - exchanging train schedules, maintenance schedules, as well as incidents and priority messages that impact highway-rail intersections (HRIs. Supports advanced traffic control strategies and enhanced traveler information.

Functional Area: TMC Demand Management Coordination

Provides the capability to gather information on regional toll, parking, and transit usage and request changes to enable dynamic pricing for demand management.

Functional Area: TMC Environmental Monitoring

Management of environmental sensors and assimilation of collected data with other current and forecast road conditions and surface weather information from weather service providers and roadway maintenance operations.

Functional Area: TMC Evacuation Support

Development, coordination, and execution of special traffic management strategies during evacuation and subsequent reentry of a population in the vicinity of a disaster or major emergency. Interfaces with emergency management and other traffic management centers.

Functional Area: TMC Freeway Management

Remotely controls ramp meters, interchange connector meters, lane control signals, mainline meters, and variable speed control systems.

Functional Area: TMC HOV Lane Management

Remotely controls HOV lane sensors, HOV lane usage signals, and ramp meters to manage use of HOV or HOT lanes; also detect HOV violators and notifies enforcement agencies.

Functional Area: TMC Incident Detection

Remotely monitors traffic sensor and surveillance systems to detect and verify incidents. Also monitors external advisory and incident reporting systems, intermodal freight depots, and border crossings for additional incident information. Identified incidents are reported to operations personnel and other centers.

Functional Area: TMC Incident Dispatch Coordination/Communication

Formulates an incident response that takes into account the incident potential, incident impacts, and/or resources required for incident management. Facilitates the dispatch of emergency response and service vehicles and coordinates the response with cooperating agencies.

Functional Area: TMC Multimodal Coordination

Provides traffic signal priority for transit vehicles based on center-to-center communications with the transit management center; also exchange traffic and transit information.

Functional Area: TMC Multimodal Crossing Management

Remotely monitors and manages multimodal crossings, such as draw bridges and other crossings between highway traffic and other modes; does not include highway-rail intersection.

Functional Area: TMC Probe Information Collection

Collects, assimilates, and disseminates vehicle probe data collected from roadside beacons and centers controlling transit vehicles, emergency vehicles, toll collection points, and route-guided vehicles.

Functional Area: TMC Regional Traffic Management

Coordination between traffic management centers in order to share traffic information between centers as well as control of traffic management field equipment. This may be used during incidents and special events and during day-to-day operations.

Functional Area: TMC Reversible Lane Management

Remotely controls traffic sensors, surveillance, and automated reversible lane equipment and lane control signals to control traffic in reversible lanes.

Functional Area: TMC Signal Control

Remotely controls traffic signal controllers to implement traffic management strategies at signalized intersections based on traffic conditions, incidents, emergency vehicle preemptions, pedestrian crossings, etc.

Functional Area: TMC Speed Monitoring

Remotely monitors vehicle speeds, and informs an enforcement agency if excessive speeds are detected. Also configures and controls speed warning systems that provide safe speed advisories to the motorist.

Functional Area: TMC Traffic Information Dissemination

Controls dissemination of traffic-related data to other centers, the media, and travelers via the driver information systems (DMS, HAR) that it operates.

Functional Area: TMC Work Zone Traffic Management

Coordination with maintenance systems using work zone images and traveler information systems (such as DMS), and distribution of work plans so that work zones are established that have minimum traffic impact.

Functional Area: Traffic Data Collection

Collection and storage of traffic management data. For use by operations personnel or data archives in the region.

Functional Area: Traffic Maintenance

Monitoring and remote diagnostics of field equipment - detect failures, issue problem reports, and track the repair or replacement of the failed equipment.