There is a massive problem of overspeeding on Nigerian highways. This problem is exacerbated by the absence of posted speed signs which though installed after reconstruction/rehabilitation are usually vandalised and not replaced. Where posted speed limits exist, they are largely observed in the breach as large pluralities of motorists exceed these posted speed limits. Using speed data from automatic traffic classifiers installed at locations on road sections on the federal highway network, this study is aimed at assessing the extent of the disparity between posted and actual speed with a view to identify areas of prevalent overspeeding, evaluate the extent of the problem, determine the trend of the problem, and better target enforcement activities on areas of high rates of overspeeding. The results from the study show that there is a prevalence of overspeeding in the highway sections studied with the maximum speed in all Sections in the range of 150 to 160 kph and up to 20 percent of vehicles traveling at speeds above 100 kph.

Speed limits; speed enforcement; traffic data; traffic safety; speed reduction practices; 85th percentile speed