The overall objectives of this research were to assess the effect of the increased speed limit on safety, travel speeds and other unanticipated impacts including the shifts in lane distribution, traffic diversions, and spillover effects, such as increase in average speeds and crashes in highway sections that did not increase their speed limits. In general, an increase in the speed limit does lead to an increase in average speeds, although the magnitude of this increase is less than the increase in the speed limit. The percentage of drivers exceeding 65 mph seems to have increased following the 1987 speed limit legislation that allowed states to increase the speed limit on rural Interstates to 65 mph. Local issues play an important role in how drivers respond to changes in speed limits. (Author/publisher)
Abstract