APPLICATION: FLOOD FORECASTING MODEL FOR LOIRE RIVER (FRANCE) - Modelling Uncertainty in Flood Forecasting Systems - page 112

Encyclopaedia Britannica, 2001). The location of the Loire River is shown in Figure 6.1
and the tributaries of the river are shown in Figure 6.2.
The major historical floods of the Loire River in recent centuries occurred in 1846,
1856 and 1866, and minor ones but still with catastrophic impact in 1980 and 1982.
During the flood of 1866, some 30,000 people were flooded in the middle Loire River
basin. The number would be as high as 300,000 if such a flood occurred in the present
day (Blancher et al., 2003). The Loire River basin is one of three pilot sites adopted by
an EC project Operational Solutions for the Management of Inundation Risks in the
Information Society (OSIRIS) (see Subsection 1.3.4). Uncertainty analysis of the
existing flood forecasting system of the Loire River has been given significant
importance in the project. The project has produced two prototypes for the Loire basin:
one for the provision of user-friendly information on hydrological situation and the other
for the tailoring of forecast information for a local diagnosis and for decision support
(Collotte et al., 2003). A separate module has also been produced for the assessment of
uncertainty in the forecast from the existing flood forecasting model (Maskey and Price,
2003a). Finally, the project increased the awareness of the need for a flood forecasting
and warning system and the importance of uncertainty considerations in flood
forecasting and warning.
The physics of the model is described in Subsection 6.1.1, and the various sources of
uncertainty in the forecasts from the model are discussed in Subsection 6.1.2. The results
of the uncertainty analyses are presented in Sections 6.2 through 6.4.
Figure 6.1. Location of Loire River (France).