Spatio-Temporal Variation of Unit Hydrograph of Brahmani River Basin

Abstract

The unit hydrograph is a direct runoff hydrograph produced when a significant amount of excess rainfall is generated uniformly over the watershed for a sufficient time. A well-known hydrologic engineering method for determining the runoff hydrograph given an excess rainfall hydrograph is the unit hydrograph method. The unit hydrograph can be developed using a variety of methods. However, most of these conventional techniques call for manually fitting the unit hydrograph across a few places, which does not ensure that the area under the unit hydrograph is uniform. Additionally, most stations are ungauged, making it challenging to develop the unit hydrograph. An analysis of the variation in the outcome is done using a spatialtemporal model, which involves showing a discharge-duration relationship for the river basin at a specified time interval. The Brahmani River basin and its four subbasins are examples of where the model has been successfully used (Jaraikela, Panposh, Boloni, Gomlai). Additionally, depending on topography, land use, and other factors, satellite data has been used to acquire yearly discharge statistics of the catchment and the area of the basins. The benefit has been maximized with the use of the model, which has also helped understand the factors that affect how much money can be saved on production while still maximizing the advantages. Additionally, the outcome of the Unit Hydrograph development of various gauging stations is examined, and the maximum discharge and time of concentration of each gauging station are displayed, showing the fluctuation in discharge throughout the period under consideration.