INTRODUCTION - Modelling Uncertainty in Flood Forecasting Systems - page 5

Figure 1.2. Alternative flood alleviation strategies (source: Penning-Rowsell
and Peerbolte, 1994)
1.2.2 Flood forecasting, warning and response systems
The realisation that we must learn to live with floods emphasises the need for a reliable
flood forecasting, warning and response system. The aim of this system is to reduce the
loss of life and property by providing credible warnings to people at flood risk and to the
authorities in charge of emergency flood protection and rescue operations. Regular river
monitoring and river flood forecasting began with the advent of the telegraph, in 1854 in
France, 1866 in Italy and 1871 in the USA (see Smith and Ward, 1998). A conceptual
structure of a FFWRS (Parker et al., 1994) is presented in Figure 1.3. This extended
structure is the result of the EUROflood (see Subsection 1.3.4) research project, which
closely resembles the structure proposed by Krzysztofowicz and Davis (1983).
The information flow in the FFWRS is either intrinsic or extrinsic, and there are also
important feedback loops. The intrinsic information flow is part of the FFWRS and
incorporates 'official' warnings of the floods. The extrinsic information flow includes, on
the other hand, 'unofficial' warnings used by the flood plain users (Parker et al., 1994).