Development of flood warning system
The health conditions of the villagers of the area were found to be serious due to severe flood years of 1987, 1988, 1991, 1993 and 1998. Seventy percent of people suffered from dysentery, diarrhea, typhoid and the remainder had fever, the rest of them showed skin infections. People in this area termed the stress in floods as
 Fig.2: Customised Dynamic GIS based flood warning system Activities of Flood Forecasting and Warning System in Bangladesh After the devastating flood of 1988, the government of Bangladesh took initiative to modernize the operation of Flood Forecasting & Warning Center (FFWC) by adopting the state of art technology and integrating it into the forecast and warning dissemination process. The present flood forecasting and warning system in operation is composed of 4 main elements, which are:
Hydrodynamic Model MIKE 11 for Flood Forecasting Rainfall Runoff Model NAM NAM is a precipitation-runoff model. This model was developed by Nielsen and Hansen (1973) at the Institute of Hydrology and Hydraulic Engineering at the Technical University of Denmark. NAM simulates the rainfall-runoff process in catchments. It operates by continuously accounting the moisture content in four different and mutually inter-related storages, i.e.: Snow Storage, Surface Storage, low Zone Storage, Ground Water Storage representing physical elements of catchment. NAM comprises of a set of linked mathematical statements describing, in simplified quantitative form, the behavior of the land phase of hydrological cycle. The model is defined as a deterministic, conceptual, lumped type of model with moderate data requirements. The model area can be divided into a number of sub-catchments. Each catchment is treated as one unit so parameters are representative of average values for the entire catchment. NAM is based on a set of linked mathematical equations, both empirical and semi empirical. NAM simulates rainfall-runoff process in rural catchments. HD Model The MIKE 11 hydrodynamic module, an implicit, finite difference model for the computation of unsteady flows in rivers and estuaries. The model can describe sub critical as well as supercritical flow conditions through a numerical scheme, which adapts according to the local flow conditions (in time and space). MIKE 11 HD applied with the dynamic wave description solves the vertically integrated equations of conservation of continuity and momentum (the Saint Venant’s equations) , based on the following assumptions:
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