Assessment of physical vulnerability of buildings to flooding in Lilongwe city, Malawi

Abstract

The research on flood vulnerability in Malawi has focused on social, economic and human vulnerability; hence, there is limited data on the physical vulnerability of buildings that could assist in flood risk reduction. The study investigated the physical vulnerability of buildings to flooding in low-income settlements of Biwi and Kawale1 in Lilongwe City. The GIS OLS regression tool and SPSS 20 were used to correlate the exposure factors and physical vulnerability of buildings. The study established that the buildings made of burnt bricks with cement mortar walls and cement floors had a low vulnerability, while buildings with burnt bricks in mud mortar walls and cement floors had a high vulnerability. The GIS’s OLS regression revealed that the physical vulnerability of buildings was significantly influenced by building typologies and floodwater depth with Sig. value .001(p<.001) and Sig. value .004(p<.005) respectively. The study established that there was variation in how the exposure factors influenced the physical vulnerability of building Types. The study concludes that building typology and floodwater depth greatly influenced the physical vulnerability of buildings. It also concludes that there was variation in how the proximity of buildings to the river, floodwater depth and floodwater duration contributed to the physical vulnerability of building Types. The study recommends that buildings should be constructed with flood resistant materials and raised foundations in flood-prone areas to reduce flood risk. It also recommends that flood vulnerability studies should be conducted in other flood prone areas to support effective citywide urban planning and management.