UseCase

Floods are hydrological events characterized by significant discharges and water levels; during floods, streams and channels are unable to convey the amount of water that has been generated through the runoff process and the water is unable to escape downstream due to high levels in the receiving streams. The consequences are sometimes very severe.

For instance, the Danube, Europe’s second longest river, was swollen with spring snowmelt and rains for much of April 2006. Floods along the river caused extensive damage in several European countries including Romania, Bulgaria, Serbia, Hungary and Austria. Fur-ther damage was caused in other Central European countries when other rivers, such as the Tisa, filled with spring runoff. Many of those rivers are tributaries to the Danube.

The floods from April 2006 along the Danube River were caused by rains on a large area in Central and South-Eastern Europe. More than 5,000 Romanians were forced to leave from their damaged homes between April 25 and April 26, 2006. The biggest part of evacuations was in the section of south-western Romania located downstream of Iron Gates hydro power plants area.

The disaster caused by the floods of April 2006 could have been diminished or even avoided if the reservoirs from Iron Gates hydro power plants area would have been discharged before the arrival of the flash flood, in order to attenuate the impact.

Flood management is usually a unique process for every river due to:

• geographical location and climate of the region;
• national / international character of watershed (responsibility of different agencies; differences in decision making process; different level of dependence on government decisions, etc.);
• physical features of the watershed and land use.

The most recent practice defines flood management as a broad spectrum of water resources aimed at reducing the loss of life and property damage; in the same time, it is important to obtain certain economic and/or social benefits from the water discharge.

Flood forecasting decision support comprises the processes of flood forecasting, flood warning, flood monitoring and real-time decision making. The primary elements of real-time flood forecasting systems must include information from: real-time data acquired from sensors reflecting current hydrological and meteorological conditions – river discharges and water levels, drainage attributes, dams’ capacity and operational information, runoff behaviours, weather forecasts, state of the river catchment, hydrological and/or hydraulic simulation models.