Urban Flood Event and Associated Damage in the Benue Valley, Nigeria

Abstract

Flooding events in the Lower Benue valley of Nigeria are often associated with huge damage to properties and loss of life in the adjoining communities. Specific objective of this study is to evaluate the impact of 2017 flood event as typical of the study area. Method used was an integrated environmental approach that combines analysis of rainfall and discharge data with social surveys, remote sensing and geographical information system. Standardized Precipitation Index (SPI), Precipitation Concentration Index (PCI) as well as flood damage curves were analysed with landuse/cover change and soil data to establish the nature of the flood and its impacts. Result showed that the flood in the study area is essentially saturation overland flow, which is more associated with saturation-excess than infiltration excess flow, and that the flood events are recurrent and predictable. 85% of the affected residents are however poor, earning an equivalent of US $4.3 daily, and live in non-reinforced concrete masonry (64%) and wooden buildings (24%). Many of the affected communities lived within flood plain and most buildings were structurally deficient. Victims received no compensation, and the properties were generally uninsured. The study recommends extensive flood control policy for the area and similar flood-prone communities.