Development and validation of a flood forecasting system for 3 small catchments in the Northwest of Spain

Flood events are becoming more frequent due to the urbanization of floodplains and to the impact of climate change. In addition, the increase of population has raised the anthropogenic pressure on water courses, triggering the negative impact of flood events. As a result of all these factors, floods have become the main type of natural disaster during the last decades. Against this background, several international organizations consider that increasing resilience is a more efficient approach towards flood damage reduction than building structural defences. However, this approach demands accurate and reliable flood forecasting systems. In this context, we present a new flood early warning system implemented in 3 catchments located on the northwest of Spain (Figure 1), with sizes of 4.95 (Cee), 16.93 (Grova) and 83.9 (Mendo) km2 . The catchments are flood prone areas and have urbanized areas that have been declared as Areas with Potentially Significant Flood Risk (APSFR) by the regional water administration. The forecasting system proposed was tested during the 2018 spring and fall seasons, with a satisfactory performance.