National Institute of Hydrology

In this study, a two dimensional numerical model in the vertical plane for simulating miscible transport of saltwater in a coastal aquifer has been developed. In order to simulate the variable density flow, the governing partial differential equation of flow and solute transport has been written in terms of pressure and concentration respectively.

The Soil Conservation Services Curve Number (SCS-CN) method presented in this report has been applied to two large catchments in sub-humid regions of India and its performance evaluated. The variation of the curve number is examined and discussed and a critical evaluation of the employment of the single linear reservoir routing technique and linear regression technique presented.

This report is a compilation of the status of natural resources as well as of the hydrological problems & constraints being faced in the Kandi belt of Jammu region of Jammu & Kashmir. Suitable actions and methods are recommended to tackle these problems in the study area.

This status report on "Hydrology of Arid Regions in India" compiles the scattered information on the subject. It is divided into nearly fourteen categories, covering sections like geology, rainfall, desertification of arid lands, position of groundwater in arid & semi-arid regions and dune landforms. 

The report attempts to provide solutions to the twin problems of waterlogging and salinity in the irrigated command area through various drainage or traditional reclamation measures viz controlling the intensity of irrigation, providing drainage system, lining, improving natural drainage, preventing seepage or adopting modern technology for application of water.

The report, a part of the regular work programme of the Flood Studies Division of the National Institute of Hydrology presents a literature review on modeling debris flow. Occurrence of debris flows is a common natural phenomenon and denotes the rapid flow of debris with sufficient water to disperse grains uniformly throughout the entire depth. Dam break flows, landslides and flows in a mountainous terrain are some of the examples.

In this study, an attempt has been made to develop a regional flood formula using L-moments for the north Brahmaputra river system. The annual maximum peak flood data of twelve gauging sites of the north bank tributaries of the river have been considered. The screening of the data has been carried out for assessing the suitability of the data for regional flood frequency analysis by computing the Discordancy Measure (Di) in terms of L-moments. Also, homogeneity of the region has been tested using the L-moment based heterogeneity measure, H.

The study evaluates the applicability of Artificial Neural Networks (ANN) in rainfall-runoff process modeling for the Ajay river basin, Jharkhand to predict the 6-hour ahead runoff at Sarath. Initially three flood events were considered for training, to find out the weights between different layers of the network. The back propagation algorithm has been used for optimization of weights. The developed ANN was validated for rest of the flood events.

In the present study, two different Artificial Neural Networks (ANN) were developed for Dharoi reservoir, Gujarat, one for flood control operation and another for conservation operation. In recent years, ANNs are increasingly being used to predict water resources variables particularly in the operation of reservoirs, the most important elements of complex water resources systems, constructed for spatial and temporal distribution of water.

The report presents guidelines for hydrological investigations in a small watershed. A watershed is an individual entity, and is a naturally occurring unit of the landscape, which contains a complex array of interlinked and interdependent resources and activities irrespective of political boundaries. In addition, it is logical unit having readily identifiable boundaries and characteristics of water movement, which helps in coordinated planning and management.