ASSESSING THE IMPACT OF LAND USE CHANGES ON FLOOD RISK IN URBAN AREAS: A CASE STUDY OF MTANDIRE, LILONGWE DISTRICT, MALAWI

Rapid and unplanned urbanization is increasingly recognized as a primary driver of elevated flood risk in sub-Saharan African cities, yet localized, evidence-based research quantifying this link remains scarce. This study assesses the impact of land use and land cover (LULC) changes on flood risk in Mtandire, an unplanned informal settlement in Lilongwe District, Malawi. The research was guided by four objectives: (1) to map and quantify LULC changes between 2015 and 2025; (2) to assess how these changes influence surface runoff and flood inundation; (3) to evaluate household perceptions, vulnerability, and coping strategies; and (4) to propose integrated land use and community-based flood mitigation strategies.
A mixed-methods design was employed, integrating remote sensing and GIS-based spatial analysis with quantitative household surveys. Sentinel-2A satellite imagery (2015 and 2025) was classified to quantify LULC changes. Flood susceptibility was modeled using a weighted overlay analysis of key environmental factors elevation, slope, rainfall, distance from streams, and vegetation cover (NDVI). Physical vulnerability was assessed by overlaying infrastructure data with flood susceptibility maps. Social vulnerability and community perceptions were captured through a structured survey of 44 randomly selected households in flood-prone and non-flood-prone zones.
The results reveal a significant LULC transformation over the ten-year period. Built-up areas expanded dramatically, becoming more continuous and dominant, largely at the expense of vegetation and open spaces. NDVI analysis confirmed a marked decline in vegetation density, from moderate-to-dense cover in 2015 (0.415–0.705) to predominantly low-to-moderate cover by 2025 (negative values to 0.67), indicating a shift toward a highly impervious landscape. Flood susceptibility mapping identified that low-lying terrain, gentle slopes (0°–10°), and proximity to drainage channels are key determinants of flood risk, with a large portion of Mtandire classified as falling within high to very high flood susceptibility zones. Physical vulnerability analysis showed that numerous dwellings and roads are situated within these high-risk areas. Household survey results indicated that flooding is a common experience among residents, yet only 25% of respondents demonstrated adequate awareness of coordinated flood response mechanisms, with most relying on reactive coping strategies.
This study concludes that land use change, specifically the rapid expansion of impervious surfaces and loss of vegetative cover, is a major driver of increased flood hazard in Mtandire. The convergence of physical susceptibility and low adaptive capacity creates a compound vulnerability that heightens flood risk. To mitigate this risk, the study recommends: (1) enforcement of land use zoning to restrict construction in flood-prone areas; (2) upgrading and regular maintenance of stormwater drainage infrastructure; (3) promotion of urban green infrastructure, including re-vegetation and tree planting; (4) community-based education programs to improve flood preparedness and awareness; and (5) the integration of GIS and hydrological modeling into local urban planning processes. The findings provide critical evidence for the Lilongwe City Council and the Department of Disaster Management Affairs (DoDMA) to inform proactive, risk-informed urban development strategies

The research was guided by four objectives: (1) to map and quantify LULC changes between 2015 and 2025; (2) to assess how these changes influence surface runoff and flood inundation; (3) to evaluate household perceptions, vulnerability, and coping strategies; and (4) to propose integrated land use and community-based flood mitigation strategies. NDVI analysis confirmed a marked decline in vegetation density, from moderate-to-dense cover in 2015 (0.415–0.705) to predominantly low-to-moderate cover by 2025 (negative values to 0.67), indicating a shift toward a highly impervious landscape. Flood susceptibility mapping identified that low-lying terrain, gentle slopes (0°–10°), and proximity to drainage channels are key determinants of flood risk, with a large portion of Mtandire classified as falling within high to very high flood susceptibility zones. To mitigate this risk, the study recommends: (1) enforcement of land use zoning to restrict construction in flood-prone areas; (2) upgrading and regular maintenance of stormwater drainage infrastructure; (3) promotion of urban green infrastructure, including re-vegetation and tree planting; (4) community-based education programs to impro

No detailed description has been provided for this study area.

Traditional authority: Lilongwe City

District: Lilongwe

Coordinates: -13.9065, 33.7532