2-Chapter-II-Data for hydrological analysis

Abstract

In the expanding modern economy, exploitation of natural resources if of primary importance. As water is one of the main natrual resource, extensive efforts are being made in every country to harness the water potential for the benefit of the people. For economic and optimum utilisation, planning, design and development of water resources, determination of the extent and availability of surface and groundwater is the first requisite and this in turn requires readily accessible, reliable and adequate observation data on the elements of hydrological cycle and related factors. Long term hydrological and meteorological data and information about physical characteristics of watersheds provide the basis for all hydrological studies as well as development and management of water resources. Further, variations in climatic characteristics both in space and time lead to uneven distribution of precipitation in our country. This uneven distribution causes highly uneven distribution of available water, which leads to floods and droughts. As the hydrological processes are continuous and quitp complex, therefore, an accurate assessment of quantities of water simultaneously passisng through all these phases becomes quite a difficult task.