The effect of an overpass on pedestrian injuries on a major highway in Kampala – Uganda

Milton Mutto, Olive C Kobusingye, Ronald R Lett
Injury Control Centre-Uganda, Makerere Medical School
The Canadian Network for International Surgery

ABSTRACT
Objectives: To describe the pedestrian population, their use of an overpass, and to assess pedestrian perceptions andresponses to the risk of traffic crashes, determine pedestrian injuries in relation to traffic flow, and compare traffic crash and pedestrian injury rates before and after the overpass construction.

Setting: The study was conducted in Nakawa trading center approximately six kilometers from the center of Kampala city on a major highway. The trading center has a busy market, small retail shops, industries, a sports stadium, offices, low cost housing estates, schools, and an estimated population of 6,226 residents, 15.1% of them students.

Methodology: Pedestrian road behavior and traffic patterns were observed, and police traffic crash records reviewed, one year before and one year after overpass construction. A convenient sample of overpass and non-overpass users was interviewedto assess their perceptions of risk.

Results: A total of 13,064 pedestrians were observed (male: female ratio= 2.2:1). The overall prevalence of pedestrian overpass use was 35.4%. A bigger proportion of females (49.1%) crossed on the overpass compared to males (29.2%). More children (79.7 %) than adults (27.3%) used the overpass. The majority of pedestrians (77.9%) were worried about their safety in traffic but only 6.6% thought of the overpass as an appropriate means to avoid traffic accidents. Traffic was not segregated by vehicle type.

Mean traffic flow varied from 41.5 vehicles per minute between 0730-0830 hours, to 39.3 vehicles per minute between 1030-1130 hours and 37.7 vehicles per minute between 1730-1830 hours. The proportion of heavy vehicles (lorries, trailers, tankers, and tractors) increased from 3.3% of total vehicle volume in the morning to 5.4% in the evening (t = 2.847, p <0.05); 44.0% of the collisions occurred in the evening with 35 pedestrian casualties before and 70 after the overpassintervention.

Conclusions: The prevalence of pedestrian overpass use was low with adult males least likely to use it. Pedestrians had a high perception of risk, which did not seem to influence overpass use. Pedestrian were more likely to be injured during slow traffic flows. There were more traffic crashes, and pedestrian injuries, but fewer fatalities after the construction of the overpass.

Key words: Overpass, Pedestrian Injuries, Urban Uganda, Accidents.