Rivers

The report presents a sedimentation study in which sedimentation rate and volume have been determined using remote sensing data in the Ukai reservoir constructed across the Tapti River in Gujarat.

We have adopted the metric system long back (1957) and there was a grace period of 10 years for transition from British units to metric units.

The report presents the effect of non hydrostatic pressure distribution on dam break flood wave movement. Dam break flood moves with non-hydrostatic pressure distribution in the vertical direction. However, almost all the mathematical models for dam break flows use Saint-Venant equation, which presume hydrostatic pressure in the vertical direction. In this report, an attempt has been made to use Boussinesq equations in the mathematical model. 

The report examines the effect of periodicity in the rainfall records on the water availability of Damanganga basin in Nasik and Thane districts of Maharashtra. Based on the rainfall-runoff record of a shorter period, runoff series for a longer period is developed using a water balance model. The per cent deviation in water availability estimations computed using short term wet and dry records from the complete records is examined. The effect of length of time-series on the water availability estimates is also studied.

In this report, a mathematical model capable of computing the flow depth and discharge in each of the branched flows is developed using gradually varied flow equations. This model can handle three flow situations viz. temporary flow diversion, a cut-off channel and a single river island. Computational capability of the model is increased to handle irregular cross sections of a river.

The report presents an original study of Cadmium adsorption based on experimental data. The effect of operating variables, like solution pH, sediment dose, contact time and particle size on the adsorption of cadmium ions on bed sediments of the highly polluted Kali river in western Uttar Pradesh has been studied.

In this study, a two-dimensional overland flow model has been developed considering random roughness coefficients and irregular land surface for the analysis of surface flow component. The one-dimensional Richards equation for subsurface flow component has been used for calculating the infiltration from the pervious area.

The report presents the status of risk based hydrologic designs that have been reported in literature and based on these, identifies a computational procedure for developing hydrologic design bases for dams and spillways. Some illustrative examples are presented in order to demonstrate the impact of risk based analysis on current design practices.

This report describes the study of regional flood frequency analysis using peak flood series data of gauging stations of Krishna basin based on at site and regional data combined using the following methods: (a) Index-Flood method (b) PWM based EVI distribution (c) PWM based GEV distribution and (d) PWM based Wakeby distribution.

The report deals with the hydrological aspects of watershed development and describes watershed components and watershed models. It gives an account of the various watershed models in details including data requirement, input, output, various physical processes and governing equation. The suitability of a particular model to Indian condition is also highlighted in the report.