Evaluating Alternative Operations Strategies to Improve Travel Time ...

SHRP 2 L11: Final Report
• adjusting lane control and dynamic message signs (DMS) upstream of the crash site, as
well as adjusting traffic controls and DMS on connected freeways
• notifying the connected arterial management systems of the forecast changes in traffic
volumes resulting from the blockage, the revised freeway management controls, and the
travel advisories
• changing pricing values on the HOT lane that is part of the Western Loop (the base
roadway pricing for the general purpose lanes remain the same).
Regional and private sector traveler information systems receive the crash notification, including
the details about that crash (location, number of lanes closed, the number of vehicles involved,
and the fact that EMS has been called). They combine that information with their own roadway
performance data feeds and make their own predictions of expected roadway and network
performance. They then broadcast those forecasts via their own distribution channels. These
channels include:
• conventional Web-based map systems (including a central system run by the regional
planning operations clearinghouse, a joint operation organization designed to ensure that
roadways and transit services operate in a seamless manner)
• in-vehicle, Vehicle Infrastructure Integration (VII)-based on-board systems that provide
voice notification of changes in roadway conditions to all Vehicle Infrastructure Integration
(VII) vehicles approaching the scene and to all vehicles that have planned itineraries that
will use either the Western Loop freeway or one of the roads forecast to carry re-routed
traffic
• mobile device text and audio messages (including links to more detailed information
accessible via Smart Phone or in-vehicle navigation systems)
• mobile and Web-based real-time navigation tools.
Other public transportation agencies (e.g., transit providers and local cities) and incident response
agencies (e.g., police, fire, and EMS) receive the crash notification details as well as the forecast
traffic conditions from the active traffic management system. These data are entered automatically
into their various traffic control, operations, and personnel and equipment dispatch systems. These
systems (in concert with the respective operations staff) make adjustments to planned operations,
including the following:
• adjusting traffic signal control plans to account for the expected levels of traffic diversion
• alerting and potentially dispatching response personnel and equipment
• adjusting bus routing to allow the best possible adherence to schedules upstream and
downstream of the crash site
• calling out additional buses and drivers to complete scheduled trips that have been delayed
and to start later trips that are dependent on delayed coaches
• sending out “late bus” and “off-route” bus notifications via multiple communications
protocols concerning all bus routes/trips affected by the crash (this includes “be aware of
possible delays” notifications on routes for trips that might be affected later in the day)
A CONCEPT OF OPERATIONS Page 122