How to manage flood forecasting in a catchment with high flood risk - experiences from the Emscher

Abstract

The Emscher area is a basin of 865 km2 , which includes nearly 2.3 million inhabitants. According to the average of 2.700 inhabitants per km2 nearly 60 % of the basin’s surface is sealed. 100 years of coal mining shaped the basin significantly. Due to that open channel system, the Emscher river shows a very quick reaction on precipitation. What does that mean for our flood forecasting? We have to record our data of the river gauges in an adequate time interval, that is usually 1 min. We have to import this recorded data from the gauges in our timeseries database every 5 minutes. In several other time intervals we’re getting our precipitation data, the radar data and the available numerical weather forecast from the German Weather Service. All this serves as input data for multiple model runs. The flood forecasting models perform continuous calculations every half an hour. All in all we’re offering an hydrological forecasting service for the operational branch of our organization so that they can handle the occurring problems. If necessary we’re performing this duty in a shift work system, so that we can offer a 24 hours service as long as needed.