News and Articles

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 performance audit report of the Accelerated Rural Water Supply Programme (ARWSP) for the period April 2002 to March 2007, conducted by the Comptroller and Auditor General (CAG), reveals numerous deficiencies in execution and implementation of works such as cases of time and cost-overrun, non-completion & delayed completion of works, non-functional & defunct works, delayed completion & non-completion of water quality mission projects, incorrect prioritization of works, wasteful and unfruitful expenditure, and expenditure on unapproved items.

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.

The report deals with expert systems for unit hydrograph analysis, an emerging technology, which may in years to come, revolutionize professional activities in the field of surface water analysis and modeling. The literature review on the topic revealed the potential of application of expert system for unit hydrograph analysis. A prototype expert system has been developed for the selection of the most appropriate model for unit hydrograph derivation of a given catchment.

The History of Water Filters website, has interesting and useful information on water filters, water treatment alternatives and water quality.