Who is the National Operations Center of Excellence for?
The National Operations Center of Excellence (NOCoE) is intended to serve the emerging transportation systems management and operations (TSM&O) community, which has become widely recognized for their important over the last several years. Unlike some more established transportation disciplines, TSM&O has not had an institutional support structure or a centralized home for collecting and disseminating best practice information and identifying research needs and capabilities throughout the United States. The NOCoE is intended to address the need for a more centralized and comprehensive set of resources to serve the TSM&O community. The Center supports efforts to reduce congestion, improve reliability, and advance overall TSM&O efforts across the United States.
What is the knowledge transfer supported by this website?
The web portal includes the following features:
- Access to all SHRP2 Reliability products and other best practice material
- Web pages for key topics of interest to the TSM&O community
- Discussion forums for managing and sharing best practices, lessons learned, emerging technologies, and research and development opportunities and capabilities
- Calendar of events of interest to the TSM&O community
- Direct links and access to resources and TSM&O activities supported by groups such as FHWA, Operations Academy, ITE, ITS America, and others
What technical services does the NOCoE offer?
The technical services include the following:
- Lead state and best practices peer exchange webinars
- National and regional summits and best practice peer exchanges
- Ongoing assessment and synthesis of emerging best practice experience
- On-call assistance to States and other organizations to identify best practice material and other resources to address specitechnical and policy issues
- Ongoing support for selected SHRP2 products
- Initial assessment of the state of transportation operations research and development in the United States and a plan integration into the NOCoE
- Training and capacity building programs
- TM&O practice area forums where practitioners can exchange technical information and advice, including a private sector forp>
What is the AASHTO Operations Technical Service Program?
The Operations Technical Service Program is the State DOTs’ component of the NOCoE. The NOCoE includes a broad array of services geared toward the transportation systems management and operations (TSM&O) community. (See a full description of the NOCoE services above.) State DOT contributions to the Operations Technical Service Program will go toward the following services:
Lead state and best practices peer exchange webinars
National and regional summits and best practice peer exchanges
Additional services, which will be developed at a later date based on the needs of the State DOT user community
Who administers the National Operations Center of Excellence?
The NOCoE is a collaborative effort of the American Association of State Highway and Transportation Officials (AASHTO), the Institute of Transportation Engineers (ITE), and the Intelligent Transportation Society of America (ITS America), with support from the Federal Highway Administration (FHWA).
What are the objectives of improving Transportation Systems Management and Operations?
Everyday congestion and delay is common in many U.S. cities and most travelers expect and plan for some delay, particularly during peak driving times. Some travelers and shippers adjust their schedules or budget extra time to allow for traffic delays. However, delay and disruption are not confined to this "recurring" congestion of peak period travel. As congestion spreads and intensifies other unexpected, unpredictable incidents, delays and disruptions tend to increase in number and severity—which significantly impact travel reliability and safety.
Transportation Systems Management and Operations (also known as traffic management or TSM&O) is a set of activities (described below) focused specifically on making the most effective use of the existing built capacity, with a special emphasis on reducing the impact of the causes of service unreliability and improving safety. Reliability is defined as the level of variability between the expected travel time (based on scheduled or average travel time) and the actual travel time experienced. The measures that improve reliability also have a positive impact on reducing crashes.
Why is reliability important?
The unpredictability of non-recurring congestion is a major performance issue for both personal and business travel in our increasingly "just in time" society. While travelers can plan for the predictable delays of recurring congestion, both commuting and business travel are impacted by the uncertainty introduced by unpredictable "non-recurring" congestion.
Unreliability also has direct economic impacts on goods transportation. Businesses rely on guaranteed deliveries to meet customer demand. Inventory management and fleet efficiency and high quality customer service are closely related to timely and predictable delivery. An efficient, reliable supply chain is essential in today's economy for all kinds of travel and transportation.
Arriving on time often requires leaving a significant "buffer" of extra time to account for possible delays—which can be both costly and inconvenient. Travelers and transportation service providers alike want travel time reliability—a consistency or dependability in travel times, as measured from day to day or across different times of day.
What are the causes of unreliability and its related impacts?
The lack of reliability is caused by crashes and breakdowns, adverse weather, construction work zones, and special events. Even in the off-peak period and outside of urban areas, level of service is increasingly unpredictable.
As shown in this pie chart of the six causes of congestion and delay, this "non-recurring congestion" alone is now responsible for over one-half of travel delay and most of the resulting unreliability.
Removing bottlenecks by increasing capacity can improve reliability. However, given the constraints on the provision of significant new capacity, it is increasingly important to operate the existing network to its fullest service potential, especially "taking back" the capacity lost to unexpected congestion, incidents, construction, weather, poor signalization etc.
How is reliability measured?
Because reliability is defined by how travel times vary over time, it is useful to develop frequency distributions to see how much variability exists. Calculating the average travel time and the size of the "buffer"—the extra time needed by travelers to ensure a high rate of on-time arrival—then helps to develop a variety of reliability measures. These measures include Planning Time, the Planning Time Index, and the Buffer Index in addition to many others. They are all based on the same underlying distribution of travel times, but describe reliability in slightly different ways:
- Planning Time—The sheer size of the buffer (the 95th percentile travel time)
- Planning Time Index—How much larger the buffer is than the "ideal" or "free flow" travel time (the ratio of the 95th percentile to the ideal)
- Buffer Index—The size of the buffer as a percentage of the average (95th percentile minus the average, divided by the average)
What are the strategies and measures that transportation agencies can take to improve reliability?
Transportation Systems Management and Operations (TSM&O) is a set of strategies to anticipate and manage traffic congestion, and to minimize the other unpredictable causes of service disruption and delay, thereby maintaining roadway capacity while improving reliability and safety.
TSM&O strategies focus directly on one or more of the specific causes of congestion, delay, and disruption directly at the point of the problem (in real time) and can reduce their impacts significantly—some by modifying roadway operations as demand varies (e.g. ramp metering); some by restoring capacity quickly after an event (e.g. incident management for crashes); some by anticipating problems (e.g. snow and ice control); and others by providing travelers with advance information and guidance to improve flow or to support effective route or travel decisions. TSM&O strategies variously combine surveillance and detection and probe data for situational awareness, as well as management centers, and advanced communications to deploy and manage responses—together with cooperative real-time field procedures to clear incidents, provide treatments, adjust road capacity or provide driver advisories. The conventional strategies are shown below.
|Strategy and Payoff||Example TSM&O Applications||B/C Ratio & Other Metrics|
|Incident/Emergency Management||Organize the management and clearance of disruptions and responses to emergencies to reduce delay and driver exposure to secondary accidents and improves reliability and responder safety via incident detection, verification, response, clearance, accident investigation, medical response, and traffic control||2:1 to 42:1 Incident duration reduced 30 to 40%|
|Road Weather Information Systems||Generate advance and current information regarding disruptive weather conditions to minimize traveler delay and improve agency efficiency of weather-related roadway maintenance via combination of roadway environmental sensing, weather information, treatment and clearance strategies and weather information dissemination||2:1 to 10:1 Travelers adjust plans up to 50% in mountainous areas|
|ITS-Supported Work Zone Traffic Management Plans||Provide dynamic, traffic-responsive traffic control (lane use, speeds, warnings) in construction work zones to improves safety to drivers and construction workers and Improve traffic flow (detection, surveillance, lane use and speed control, signs, signals) for specific projects.||2:1 to 42:1 300% reduction in dangerous merges|
|Traffic-Responsive or Traffic-Adaptive Signals||Provide traffic-responsive/traffic adaptive signal operations at intersections for corridor and network optimization to minimizes delay throughout corridor and network via traffic detection, transit vehicle pre-emption and appropriate signal control and network level regimes||17:1 to 62:1 Up to 2 to 3% reduction in delay|
|Ramp Metering||Control traffic flow (rate and spacing) entering freeway based on actual traffic conditions to minimize main line traffic disruptions and safety hazards and improves travel time via freeway volume detection and related traffic-responsive ramp signals||15:1 Up to 15% reduction in delay|
|Freeway Operations and Active Traffic Management||Harmonize speeds and balance lane use (including shoulders) to minimize queuing, delay, and additional crashes via variable speed limits and advisories/lane use controls including detection, communications and dynamic message signs||Up to 25% reduction in crashes and 10 to 20% reduction in delay|
|Advanced Traveler Information||Provide current and anticipated travel and weather conditions, route, and mode options (and other information) to support travelers' optimal choice of trip route, timing, and mode via multiple media—Web, 511 phone, Twitter, email, text—and via overhead or roadside changeable messaging and in-vehicle information||3% decreases in crashes|
How are TSM&O strategies developed and applied?
TSM&O requires a different set of agency capabilities and arrangements for implementation by comparison with traditional capacity improvements. Each specific strategy (as shown above) depends on characteristic operational concepts and systems together with related procedures and protocols for their implementation in real time.
Development and application of the needed systems, procedures and protocols depend on certain technical and business processes such as planning and programming, systems engineering, and performance measurement, specifically oriented to supporting development and application of the strategies. The technical and business processes, in turn, require a supportive implementation environment in terms of leadership, organization and staffing, resources, and collaborative relationships.
The knowledge resources required to implement effective TSM&O strategies and to develop the necessary processes and institutional arrangements are part of the knowledge transfer supported by the National Operations Center of Excellence.