DEVELOPMENT OF PHYSIOGRAPHIC PARAMETERS AND DESIGN FLOOD ESTIMATION OF DOIMUKH HYDRO ELECTRIC PROJECT USING REMOTE SENSING & GIS

Abstract

The most widely used method for the estimation of flood hydrograph which is derived from a known storm in a catchment area uses historical rainfall-runoff data and unit hydrographs developed from them. These techniques are highly unreliable because of the physical and climatic changes in the catchment and their uses to ungauged catchments. These drawbacks can be overcome by use of the synthetic unit hydrograph (SUH), which is a physically based rainfall-runoff estimation method. The physiographic parameters of the Doimukh basin were estimated from 30 m ASTER (Advanced Space Borne Thermal Emission and Reflection Radiometer Sensor) DEM and using ARC-GIS 10.2, 3DEM, and GeoHMS Software. The aim of this study was to estimate the development of Physiographic Parameters for River Dicrang with special reference to DOIMUKH Hydro Electric Project‟s watershed, of the site situated at Itanagar , Arunachal Pradesh. This Report provides an overview of estimation of physiographic parameter, the Development of Synthetic Unit Hydrograph (SUH) & subsequently Design flood of the project. The same result has been compare with different method of convention approach i.e flood frequency analysis. The flood frequency method is based on statistical approach in which the past year data has been used for calculate the design flood for different return period. The return period is depending on the importance of the structure, their storage and economy of the structure.