Gully erosion puts millions of urban residents in Congo in danger
Urban gullies are large, deep erosion channels that suddenly form in urban areas and put million of people at risk. Triggered by intense rainfall, they are commonly the consequence of uncontrolled urbanisation, poor spatial planning and inadequate infrastructure.
This largely man-made geo-hydrological hazard - typical for the Anthropocene - can lead to important impacts on people, houses and infrastructure. However, comprehensive assessments of the occurrence of urban gullies and their impacts were lacking.
In our research, just published in Nature, we mapped over 2,900 urban across 26 cities in the DR Congo. These gullies already have a combined length of more than 730 km. We show that, currently, ca. 12,000 people per year lose their home due to the formation and expansion of these gullies. Over 3 million urban Congolese residents live in the potential expansion zones of existing gullies and face important risks. Hence, these urban gullies are an underestimated and growing threat, not only in the DR Congo but in many cities across the Global South. Nevertheless, they are very rarely recognised as a hazard or taken into consideration in policies for disaster risk reduction.
Figure: Urban gully expansion and its associated population displacement.
This research is the result of a join effort of a team of Congolese and Belgian researchers, including the GeoRiskA team.
📄 The paper (Open Access) “Mapping urban gullies in the Democratic Republic of the Congo” by Ilombe Mawe et al. has been published in Nature (DOI 10.1038/s41586-025-09371-7)
📰 Editorial: https://www.nature.com/articles/d41586-025-02684-7
📰 News article: https://www.nature.com/articles/d41586-025-02745-x
📰 News & Views: https://www.nature.com/articles/d41586-025-02426-9
📰 “Behind the Paper” blogpost
