Testing the impact and feasibility of 30 km/h speed limit zones at schools

Abstract

Local authorities such as the City of Tshwane (CoT) Municipality are confronted on a daily basis with road traffic safety challenges around schools. School principals, councillors, parents, scholars and neighbourhood residents approach local authorities for assistance to address unlawful driver behaviour and implement remedial measures to enhance the safety of scholars at schools. One potential countermeasure is the implementation of 30 km/h speed limit zones at schools. However, such speed limit zones to improve pedestrian safety on lower order roads around schools are not common in South Africa. Very little before-and-after data are available to understand and evaluate the effectiveness of such zones. The objective of this study was to measure the effectiveness of introducing a 30 km/h speed limit zone strategy at schools, where high pedestrian activity and non-motorised transport are present and can be endangered by vehicular traffic. Thirty kilometre per hour speed limit school zone signs were designed and installed to enforce a 30 km/h speed limit for specific periods of time during school arrival and departure times. Three school sites in different areas in the City of Tshwane Municipality were selected as case study sites. Before-and-after speed data were used to test the hypothesis that the 30 km/h speed limit zone has no effect on the mean and variance of speed. The results showed that the speeds recorded after the implementation of the 30 km/h speed limit school zone signs varied between 30 km/h and 35 km/h at all the sites. The mean speed at all the sites was lower than before, for both passenger and public transport vehicles. A control site was also used to ensure that the results were not caused by spurious fluctuations. Qualitative feedback from the schools showed widespread acceptance of the measure. The results of this study show that international best practice initiatives can be applied with great success and that 30 km/h speed limit school zones can contribute to safer roads and support the National Road Safety Strategy to reduce the increasing trend in road traffic fatalities.