Travel Time Signs
Travel Time Signs are traditional panel signs, usually with two destinations shown and electronic inserts indicating the minutes of travel to those destinations.
The time estimates are based on information gathered from road sensors that measure a variety of factors, including average vehicle speed and traffic volumes. INDOT has developed algorithms to ensure the travel time information displayed is as accurate as possible.
Because Travel Time Signs include distances to downstream locations, they enable motorists to determine if the posted travel time reflects free-flow conditions or congestion ahead. Motorists use this travel time information along with downstream lane-restricting information, which is displayed on Dynamic Message Signs, to make informed decisions about their trip ahead.
INDOT deployed the first Travel Time Signs on westbound I-80/94 in northwest Indiana in January 2010. Since then, INDOT has installed multiple Travel Time Signs in northwest Indiana and the Indianapolis area.
Dynamic Message Signs
DMS provide dynamic operational information to motorists, including incident, traffic, and road condition information, emergency alerts, travel time information, and other advisories at strategic locations on high-volume freeways. Motorists can use this information to select an alternate route or divert, delay, or even cancel their trip to avoid traffic delays
INDOT has installed 69 overhead Dynamic Message Signs in Indiana. A total of 46 are located in the Indianapolis area. Another 12 signs are in northwest Indiana near Chicago, while southern Indiana near Louisville, Ky., has nine signs. Two signs are located in the Fort Wayne area. The first overhead Dynamic Message Signs in Indiana were deployed in 1998. Additional DMS are planned for the Indianapolis area and northwest Indiana in Fiscal Year 2016.
Most travel information signs are financed using Federal Congestion Mitigation and Air Quality (CMAQ) funds. CMAQ funds can only be used on eligible projects in counties that are either in Non-Attainment or Maintenance status for National Ambient Air Quality Standards. These funds can only be used on very limited types of transportation-related projects.
CMAQ funds cannot be used for any other purpose, such as the majority of highway projects (such as resurfacing, bridge work, or added capacity projects). INDOT intends to secure CMAQ funds for planned future Travel Time Signs and Dynamic Message Signs.
Edward D Cox
Managing Engineer Corridor Operations
Indiana Department of Transportation
Traffic Management Center
8620 East 21st Street
Indianapolis, IN 46219