National Institute of Hydrology

The report describes the results of the study of arsenic pollution in groundwater in Nadia as well as the hydro-chemical study of the river Hoogly in West Bengal. The alluvial tract along the river Hoogly covering a stretch of around 470 km encompassing eight districts is affected by arsenic pollution of ground water, the source being geogenic.

In the present study, design flood estimation of Morel catchment of Rajasthan state is computed using the Synder approach, regional relationships as proposed by Central Water Commission, Clark's model, Soil Conservation Services (SCS) method and Geomorphological Instantaneous Unit Hydrograph (GIUH) based approach. 

The report presents an interactive software that has been developed to not only provide design flood estimates for large as well as small sized catchments but also help the users analyse their historical rainfall-runoff records for calibration and validation of the various techniques for part or whole of the catchment and river reaches.

The report describes a software developed by the National Institute of Hydrology (NIH) for reservoir analysis in view of the importance of reservoir operation problem in the Indian context and the non-availability of generalized software for reservoir analysis.

The study attempts to estimate the recharge to groundwater due to rainfall and irrigation using tritium tagging techniques in parts of Narsinghpur district under the Narmada catchment in Madhya Pradesh. The estimation of recharge to groundwater is crucial to better water resources management, particularly in arid and semi-arid regions.

The study was conducted with the objective of establishing the relationship between spectral reflectance of rice canopy and crop growth. Significant relationship was developed between spectral indices and growth period. The coefficient of correlation between crop growth period and spectral reflectance ranged from 0.41 to 0.97 for the plant growth stages and canopy reflectance in single band and ratio spectra.

The study presents detailed investigations of the chemical quality of groundwater in Jammu and Kathua districts (J & K), carried out to evaluate the suitability of water for various uses. The quality of groundwater of the area has been studied based on the physico-chemical analysis of thirty seven water samples collected from open wells between June and December, 1996.

Various parameters like pH, conductance, alkalinity, hardness, chloride, sulphate, sodium, potassium, calcium and magnesium have been determined for all the samples and compared with the standards to evaluate its suitability for drinking and irrigation purposes.

Irrigation water quality has been computed on the basis of Doneen’s Permeability Index and residual Sodium Carbonate. The higher values of some parameters at certain locations indicate the contamination in groundwater and make the water unsuitable for specific applications.

The study attempts to carry out field testing of the weighing raingauge for measurement of rainfall, which is at the core of all hydrological measurements. The tipping bucket rain gauges are generally used for automated recording of rainfall data. It has been reported that the tipping bucket mechanism of such raingauges frequently malfunctions and gives erroneous data, especially during high intensity rainstorms.

The Systems Hydrologique European – European Hydrological System (SHE) is a physically based distributed model and it provides a useful setup for understanding the importance of evaporation data and soil parameters. 

In this study, single column hydrologic simulations have been carried out for examining the sensitivity of this model to pan evaporation data of the various stations as well as the increase in conductivity of the unsaturated zone. Furthermore, the reduction in the value of exponent appearing in the Averjanov’s formula and reduction in the values of moisture content at wilting point and residual water content has been studied for a single grid of 2 km X 2 km size of the Narmada river.

In this study, unsteady flow towards a fully penetrating well screened in both the aquifers of a two-aquifer system separated by an aquitard has been analyzed using numerical approach. Existence of multi-aquifer systems is common in a sedimentary basin.