Evaluating Alternative Operations Strategies to Improve Travel Time ...

SHRP 2 L11: Final Appendices
Agency Measures
This section presents measures from some of the Departments of Transportation and Metropolitan
Planning Organizations, which demonstrate management and reporting of reliability and traveltime
information. The following table summarizes some of the best practices:
Agency Performance Reporting
Method
WSDOT: Washington State The Gray Notebook
DOT
GRTA: Georgia Regional
Transportation Authority
FDOT: Florida Department of
Transportation
The Transportation Metropolitan
Atlanta Performance (MAP)
Report
The 2020 Florida Transportation
Plan - Florida’s Mobility
Performance Measures
San Antonio-Bexar City MPO The 2030 Metropolitan
Transportation Plan - the Texas
Congestion Index (TCI)
Puget Sound Regional
Council - Seattle, Washington
Metropolitan Transportation
Commission - San Francisco
Bay Region
Southern California
Association of Governments
Destination 2030: Update
(America’s Best Plan)
Transportation 2030 Plan -
Reliability is listed as one of the
six goals
The Final 2008 Regional
Transportation Plan
Performance Data
Average Clearance time (in minutes) for major (90+ minute) incidents
on key Puget Sound corridors
Annual weekday hours of delay statewide on highways compared to
maximum throughput (51 MPH) in thousand hours.
Freeway Travel Time Index (TTI): the ratio of the average travel time
over the free-flow travel time obtained for a certain portion or segment
of the freeway system.
Freeway Planning Time Index: the planning time index (PTI) and the
buffer time index (BTI).
- PTI is the ratio of the 95 th percentile travel time - or planning time -
over the free-flow travel time obtained for a certain portion or segment
of the freeway system.
- BTI is defined as the difference between the 95 th percentile travel and
the average travel time.
Daily Vehicle Miles Traveled per Licensed Driver/Person
Roadway Clearance Time: defined as the “time between first recordable
awareness (detection/notification/verification) of an incident by a
responsible agency and first confirmation that all lanes are available for
traffic flow.”
Person miles traveled
Truck miles traveled
Vehicle miles traveled
Person trips
Average speed
Delay
Average travel time
Average trip time
Reliability
Maneuverability
% system heavily congested
% travel heavily congested
Vehicles per lane mile
Duration of congestion
Texas Congestion Index (TCI), which is a variation of the Travel Time
Index developed by the Texas Transportation Institute for the Annual
Urban Mobility Report
HOV lanes, ITS, and reliability of transit service
Capacity added to the Metropolitan Transportation System
Levels of service in congested corridors
Progress with freeway ramp meters and traffic signal retiming
On-time transit performance
Effectiveness of incident management strategies
New transit connectivity projects
Progress in improving traveler information
The statistical concept of standard deviation. The indicator is computed
by dividing the standard deviation of travel time for a given trip by the
average travel time of that trip, measured over many days and weeks.
Source: State DOT websites
RELIABILITY PERFORMANCE MEASURES AVAILABLE TO AGENCIES Page A-2