Monitoring land use challenges driven by peri-urbanisation around Kigali City, Rwanda

Urbanisation is accelerating globally, with significant impacts in Sub-Saharan Africa, where peri-urban areas are rapidly expanding, often without adequate planning or infrastructures. This study investigates the environmental sustainability challenges driven by rapid peri-urbanisation in Runda Sector, Kamonyi District, on the fringes of the City of Kigali, Rwanda, between 2010 and 2024. Using a combination of remotely sensed data, GIS analysis, field observations, and semi-structured interviews with 53 local stakeholders, the study (1) examines the spatial patterns of urban expansion; (2) identifies land use changes and associated environmental challenges; and (3) proposes sustainable urban development and mitigation strategies for environmental challenges. Findings show that the built-up area expanded from 560.5 ha in 2010 to 895.0 ha in 2024, while forest cover decreased by 279.0 ha between 2010 and 2020, recovering slightly by 2024 due to reforestation. Similarly, wetlands initially declined from 529.3 ha in 2010 to 387.3 ha in 2020, but later increased to 573.6 ha by 2024, owing to wetland restoration programs. Grasslands declined by 322.2 ha, and cropland by 133.4 ha in 2020–2024. Built-up expansion also occurred on slopes exceeding 35%, increasing from 90 ha in 2010 to 195.4 ha in 2024, despite legal restrictions, raising concerns over erosion and flood risks. These findings demonstrate: (1) significant urban encroachment into environmentally sensitive areas; (2) inadequate enforcement of zoning laws and weak land governance; and (3) increasing vulnerability of natural ecosystems and agricultural land to unregulated development. To mitigate these challenges, the study recommends (1) strict enforcement of slope and wetland-based zoning; (2) participatory land use planning; and (3) investment in green infrastructures and affordable housing to curb outward migration and environmental degradation. These strategies are important for promoting balanced urban growth and environmental sustainability in Kigali's peri-urban areas and other rapidly urbanizing regions in Sub-Saharan Africa.