Infrastructure Resilience Optimization for Climate Adaptation

This figure illustrates how the average road network distance from Dakar and Tambacounda to other parts of Senegal increases as flooding worsens. More regions become inaccessible (represented in black) from the starting point, while the distance to regions that remain accessible increases (shown by the color bar) as the most direct paths to them become flooded. In particular, a flood of return period 75 years is enough to largely isolate the city of Tambacounda, whereas the road network around the capital would still allow access to most of western and central Senegal in this scenario.

One strategy for improving road network accessibility is to upgrade subsets of roads such that the number of infeasible trips under a given flooding scenario is minimized. With any strategy, there are naturally trade-offs between accessibility improvements and the economic cost of the scheme. This figure shows how the road network distance from Dakar and Tambacounda to other regions improves as the budget available for repairs minimizing the number of infeasible trips is raised. In particular, we see a dramatic improvement in interregional accessibility when 300km of roads are upgraded.