Integrated Decision Support for Sustainable Mobility in a Motorcycle- Dominated African City

In many growing cities across Africa, the streets tell a story of adaptation. Where formal bus networks are thin or non-existent, people turn to what is available: the motorcycle taxi. Known locally as the boda-boda, these two-wheeled vehicles weave through traffic, offering door-to-door service that fills the gaps left by larger transport systems. They are a lifeline for commuters, but their sheer numbers create a complex puzzle for city planners. A road might look fine on the surface, yet fail to move people efficiently. Conversely, a road might be packed with vehicles but still leave passengers stranded or stuck in long delays. The challenge for urban scientists is no longer just about fixing potholes or counting cars; it is about understanding how the physical condition of a road, the mix of vehicles using it, and the daily experience of the people riding it all fit together. If a city wants to move forward, it must decide whether to simply build more lanes or to reorganize how people travel within the space they already have.

This question lies at the heart of a new study focused on a specific stretch of road in Mbarara, a secondary city in southwestern Uganda. Researchers from Kampala International University chose Buremba Road, a three-and-a-half-kilometer corridor that connects the city center with schools, markets, and homes. They wanted to see if the road was truly working for the people who depended on it. To do this, they did not rely on a single type of data. Instead, they combined a physical inspection of the road surface, a manual count of every vehicle passing through during busy hours, and a survey of nearly one hundred commuters about their travel times and costs. They also spoke with local experts who manage traffic and infrastructure. By weaving these different threads together, the team built a complete picture of how the corridor functions, moving beyond simple engineering metrics to see the human reality of the commute.

The physical inspection revealed a road that was still usable but showing its age. The pavement, which is the surface layer of the road, received a score that placed it in the "fair" category. This means the road is not broken enough to require total reconstruction, but it is vulnerable. The most common problems were potholes and failures in the drainage system, where water cannot escape the road surface. While the road itself could handle the weight of vehicles, the surroundings were less supportive. There were few safe places for pedestrians to walk, crossings were scarce, street lighting was inconsistent, and there were no dedicated lanes for bicycles or people walking. These missing pieces made the environment difficult and sometimes dangerous for anyone not driving a motorized vehicle.

When the researchers stood on the roadside and counted the vehicles, a clear pattern emerged. Motorcycles were by far the most common vehicle, making up nearly eighty percent of all traffic. The remaining vehicles were mostly cars, minibuses, and trucks. During the busiest times of the day, the number of vehicles trying to use the road reached a level that exceeded what the two-lane road could comfortably handle. The road was operating under stress, with more vehicles trying to pass through than the space could efficiently accommodate. This created a situation where the road was physically intact but functionally overwhelmed. The study found that the traffic flow had reached a point of breakdown, where delays become frequent and movement slows significantly, a condition that engineers describe as a failure of the system's capacity to serve the demand.

The experience of the commuters told a similar story of strain. The people surveyed reported that a single trip along this corridor took, on average, thirty-eight minutes, though some trips took as little as fifteen minutes and others stretched to over an hour. The cost of these trips varied widely, with the average rider paying a specific amount in local currency that fluctuated significantly depending on the time of day and the specific route. While motorcycles were the primary mode of transport for the majority of those surveyed, a significant portion of commuters still walked, highlighting that even without safe sidewalks, people continue to move on foot. The data showed that while the road was crowded, the system was not moving people efficiently. The high number of low-occupancy motorcycles meant that a large volume of space was being used to transport relatively few people, contributing to the congestion.

To find a way forward, the research team evaluated four different strategies for improving the corridor. They weighed these options against six important factors: how affordable they would be, how well they would improve access to jobs and services, how safe they would make the streets, how easy they would be to implement, their impact on the environment, and whether the public would accept them. The options included organizing the existing minibus system into a more structured network, building a simplified bus rapid transit line, improving infrastructure for walking and cycling, and creating a system where vehicles arrive only when requested.

The analysis pointed to a clear favorite. An organized minibus system emerged as the most promising solution, scoring highest because it offered the best balance of cost, accessibility, and practicality for the city's current situation. This approach does not require the massive investment of a full bus rapid transit system but offers a significant upgrade over the current fragmented service. The study found that this option was distinctly better than the next best alternative, a simplified bus rapid transit system, which in turn was very close in score to improving infrastructure for walking and cycling. The researchers noted that these last two options are not rivals but partners; safe walking paths and crossings are essential for getting people to and from the buses, making them a necessary part of the overall package rather than a competing choice.

The study concludes that the problem on Buremba Road is not just about the condition of the asphalt. Even though the road surface is serviceable, the mobility system is failing because of how the traffic is organized and the lack of safe spaces for non-drivers. The solution, therefore, is not to simply fix the road or to ban motorcycles. Instead, the researchers propose a staged transition. This plan involves organizing the minibus services to run more efficiently, regulating the motorcycle taxis to act as feeders that bring people to the main routes, and simultaneously building safe sidewalks and drainage systems. By treating the road as a shared space for people rather than just a channel for vehicles, the city can move toward a system that is safer, more efficient, and better suited to the needs of its residents. The findings suggest that for many African cities, the path to better mobility lies in reorganizing existing resources and integrating different modes of transport, rather than waiting for large-scale infrastructure projects that may never come.