Flood Risk Management Strategies for Urban Local Government Areas in Lagos State

Lagos State, Nigeria's commercial capital and most densely populated state in the South West geopolitical zone, faces escalating flood risks driven by accelerating urbanisation, sea level rise, and inadequate stormwater drainage infrastructure that demands comprehensive and professionally managed risk reduction strategies. This study evaluates existing flood risk management strategies in four high-risk urban local government areas of Lagos State: Kosofe, Alimosho, Ojo, and Somolu, identifying implementation gaps and proposing improved management frameworks. Flood event records, drainage infrastructure inventories, and urban planning documents were reviewed to characterise institutional responses to flood risk across the four study areas. Structured interviews were conducted with 48 key informants including Lagos State Emergency Management Agency officers, local government drainage engineers, community development association leaders, and academics specialising in urban hydrology. A process mapping exercise documented the current risk management cycle from hazard monitoring through response and recovery. Results identify fragmented institutional responsibilities, underfunded drainage maintenance budgets, and absence of community-level early warning integration as the most critical systemic gaps. All four local government areas lack current flood hazard maps, and risk-sensitive land use controls are not applied in practice. The study recommends establishment of a unified Lagos Flood Risk Coordination Authority with dedicated technical and financial resources, mandatory flood impact assessments for all new developments in flood-prone zones, and community resilience programmes modelled on successful international urban flood management examples. Keywords: flood risk management, Lagos State, urban drainage, South West Nigeria, institutional frameworks.