Strategy #36
Variable Speed
Identify and apply variable speed advisory technology
to improve highway/roadway operations and safety.
Background
Speed continues to jeopardize motorist safety and is a significant contributing factor to crashes on the highways and roadways in the United States. To curtail unsafe vehicle speeds, variable speed advisory signs should be used at strategic roadway locations to advise motorists of their unsafe speed and/or to alert the motorist to a safe speed for the prevailing weather or roadway conditions.
Actions
- Install advisory signs with recommended speeds near areas that frequently experience vehicle incidents (for instance, a super-elevated ramp with a restrictive radius where trucks often run off or roll over).
- Rotate the use of mobile speed advisory trailers to locations where excessive vehicle speeds are apparent.
- Use electronically variable speed limit systems where motorists need supplementary signage that reflects limited visibility, snow/ice, or other weather or road conditions. Justify these speed limits with engineering and traffic surveys.
- Promote the use of highway safety messages via variable messages signs.
Benefits
- Reduced vehicle collisions and incidents.
- Reduced motorist fatalities and injuries.
- Reduced property damage.
- Improved highway and roadway traffic flow (mobility).
- Reduced traffic congestion.
- Expands the “reach” of traffic safety messages.
Other Considerations
- Cost of the technology.
- Increased skills, expertise and training for personnel to support and operate.
- Accuracy and reliability of technology.
- Potential increase in support staff requirements, which may cause a reduction in existing personnel levels.
- Inter-connectivity with other systems and privacy issues of shared systems.
- Possible liability issues if equipment in not maintained properly.
- Need for statutory changes to support variable speed limits.