School of Engineering


Solving Traffic Congestion Problems Caused by Rainfall

Solving Traffic Congestion Problems Caused by Rainfall

Dr Stephen Olukayode Ibijola is ecstatic to graduate from UKZN with a PhD that looked into congestion problems on highway intersections as well as drivers’ behaviour during rainfall.

Traffic circles or roundabouts are priority intersections in South Africa with a unique yield rule. The fixed features and yield rule do not change relative to rainfall. However, vehicular flow and driver behaviour are often affected by ambient conditions such as rainfall.

Consequently, the study investigated the influence of rainfall on the quality of service delivery at multi-lane roundabouts and their implications on headway. ‘Based on the hypothesis that rainfall, irrespective of intensity, has adverse effects on the quality of service delivery and time headway at roundabouts, an impact study was carried out in Durban. Entry, circulating traffic flow and rainfall data were collected at four selected sites. Over two million traffic volume data was collected during the August to February rainy season. Empirical data was collected continuously for six weeks on each selected roundabout. Rain data was collected from surface rain gauge stations,’ said Ibijola.

The study concluded that rainfall has an adverse effect on the Functional Quality Service (FQS), and that heavy rainfall has the most significant impact on FQS at roundabouts.

Ibijola, who completed his BSc at the University of Benin, Nigeria, said he decided to do his PhD studies at UKZN because of its status of being rated among the best transportation engineering institution in Africa.

After being employed at the Ekiti State Ministry of Works and Transportation’s Civil Engineering Department, he was involved in highway, construction and supervision which prompted him to complete a Master’s degree in the field of Transport Engineering at the Federal University of Technology Akure.

He plans to “stand out” in the field of Transportation Engineering by providing a long-lasting solution to highway and traffic problems in the near future.

Words: Manqoba Hadebe 

Photograph: Rajesh Jantilal