Evaluating Alternative Operations Strategies to Improve Travel Time ...

SHRP 2 L11: Final Report
Improved transportation system reliability does not mean that all travel would take place at the
speed limit. It means that consumers will be able to obtain estimates of how long a trip will take,
know that the estimate is reasonably accurate, and make travel decisions accordingly.
NEXT STEPS FOR MIGRATING TOWARD A MORE “RELIABLE”
FUTURE
The most important changes necessary to produce significant improvements in travel reliability are
(1) to bring market forces to bear on both travel decisions (which results from better and more
ubiquitous information available to all travelers) and (2) to provide additional supply in a way that
is balanced against demand. As noted at the beginning of this summary, a more reliable roadway
system will only occur on a sustainable long-term basis when travel demand and roadway capacity
are in balance. Achieving that balance requires a combination of technical improvements. But,
those technical improvements are themselves dependent upon institutional and attitudinal changes
that drive both how we operate our transportation system and how our customers
(travelers/shippers/carriers) make their travel decisions.
Travel is an economic good. It behaves like all economic goods: when price is low, demand is
high; when price is higher, demand is lower. Because price is not an integral part of most current
roadway travel decisions, 1) roadway agencies are constantly faced with situations in which
demand exceeds capacity; 2) the resources to remedy that situation are not being generated and
deployed to meet those demands; and 3) travelers have insufficient information and incentive to
change their behavior to travel at less congested times or via other modes.
There is a strong argument for market forces to apply to both demand and supply. Economic
efficiency increases when the full social costs of travel becomes part of the travel decision. In
addition, there is better resource allocation when the funding generated by that travel is spent in
the corridors where it is generated to support needed increases in supply (travel capacity) .These
ideas constitute a major philosophical shift from how we currently operate our roadway system.
As a practical matter, there will continue to be reliance on free roads, a growing emphasis on toll
roads and pricing, and the emergence of innovative or relatively untried approaches for addressing
imbalances between supply and demand.
Regardless, once the shift to a more information-driven approach to travel has occurred, there will
be increased demand for expenditure accountability. This would create the incentive systems that
are needed to encourage the technical and institutional changes that would result in the
appropriate level of travel time reliability (as valued by travelers). These technical and institutional
changes include the following:
• an increase in the quality and completeness of traveler information systems, as consumers
of travel services demand better information about their choices, the price for their choices,
and the performance of those choices
• a continued rise in the importance of improvements to the real-time control and operational
performance of transportation systems
• the capability to fully integrate highway operations with arterial and transit system
operations
• better, faster, and more capable systems for responding to capacity disruptions (incidents,
weather, etc.) and for restoring capacity lost to those disruptions
EXECUTIVE SUMMARY
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