Uncovering the Spillover Effect from Posted Speed Limit Changes: A Tool to Examine Potential Safety Concerns
The AAA Foundation for Traffic Safety has been examining topics related to posted speed limits and speeding since 2017 and has published several documents thus far that described practices for setting posted speed limits in the U.S.; the impact of speed increases on driver safety from vehicle crash tests; and traffic fatalities in relation to speed limits and speeding. Information presented in this technical report represents AAA Foundation’s continued efforts in this body of work, with the goal to bring awareness about the dangers of speeding and potential traffic safety consequences from raising the
posted speed limit.
Work presented in this report used a geospatial analysis tool to compare ‘before’ and ‘after’ speed-related crashes on local roads, when posted speed limits were increased on nearby Interstate segments. Multiple traffic safety concerns were presented graphically from three case studies examined in this work. This report can be a useful resource for transportation practitioners when considering making changes to posted speed limits by recognizing potential safety impacts on surrounding roads, proper countermeasures can be planned and implemented.
Read the full study here.