Warning for urban flooding requires real-time and high resolution rainfall data in space and time, as well as detailed flood models. This is a challenge in data scarce regions, especially when no ground radars are available and digital elevation maps are generally coarse.
HKV implemented an Urban Flash Flood Forecasting System (UFFFS) for three cities in the Volta basin: Bondoukou in Ivory Coast, Tamale in Ghana and Mango in Togo. This UFFFS provides alerts based on nowcast of heavy rainfalls in combination with a risk assessment on the impacts of extreme rainfalls in the urban environment.
UFFFS makes use of openly available rainfall products provided by the Meteosat satellite and combines these rainfall estimates with state-of-the-art nowcasting models, that forecast rainfall for the next few hours. The flood risk assessment is based on open-source data sets and enhanced by field surveys of the local drainage system.
The final (operational) product of UFFFS is disseminated through the VoltAlarm platform developed by CIMA Research Foundation within the Volta Flood and Drought Management (VFDM) project, implemented by the World Meteorological Organization (WMO), Volta Basin Authority and Global Water Partnership-West Africa.
