Rivers

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.

The study applies a hydraulic simulation model, Hydrologic Engineering Centre (HEC-1) to Baitarni river for modeling hourly flows of the river at Anandapur gauging site. HEC-1 model had been developed by US Army Corps of Engineers, for rainfall-runoff modeling. It provides a powerful automatic optimization technique for estimation of some of the parameters. The optimization technique of the model has been utilized in the present study and model parameters have been calibrated and validated for the study area.

The report uses the Soil Conservation Services (SCS, 1956), Curve Number (SCS-CN) method, a widely used event based rainfall-runoff method for simulating daily rainfall-runoff data of three catchments, viz., Ramganga and Hemavathi catchments of the sub-humid regions and Sabarmati catchment of the arid region of India.

In the model formulation, the daily variation of parameter, potential maximum retention is governed by the known antecedent moisture condition. Hydrologic simulation studies provide a useful and important input to water resources planning and watershed management practices.

The study deals with flood estimation through computation of a flood hydrograph for the ungauged Narmada catchment upto Jamtara using the physical and geo-morphological characteristics of the catchment. The catchment area of 17100 sqkm has been sub-divided into five sub-catchments for the purpose of flood estimation.

The study uses HEC-RAS to analyse the water surface profiles of Malaprabha river system upto Khanapur for different combinations of discharges through various reaches of the river system. The river system is divided into eleven reaches, and forty one cross sections have been measured and interpolated within these reaches.

Discharge values have been assigned for different reaches according to the ratio of contributing area for each reach. The bridge across the river at Khanapur is reproduced in the modeling system to test its capabilities. Various return period floods have been allowed to pass through the river system to compute the individual water surface profiles.

A detailed survey of the river Hindon was carried out to understand the nature of waste effluents and their impact on water quality.  As per the study, the river water is subject to varying degrees of pollution, caused by numerous untreated waste outfalls of municipal and industrial effluents.

The main sources, which create pollution in the river, include municipal wastes of Saharanpur, Muzaffarnagar and Ghaziabad districts received through tributaries as well as direct outfalls. In the non-monsoon months, the river is completely dry, right from its origin upto Saharanpur town. The effluents of Nagdev nala and Star Paper Mill at Saharanpur generate the flow of water in the river.

The study attempts to find out the pollution potential in the Hindon river, a polluted river in western Uttar Pradesh. Qualitative and quantitative estimation of pesticides was done using gas chromatography. Among various organic, inorganic and biological water pollutants, pesticides are very dangerous and harmful because of their carcinogenic properties. Pesticides are bio-accumulative and relatively stable and therefore require close monitoring.

The study attempts to do a field and laboratory determination of soil moisture characteristics such as particle size distribution, hydraulic conductivity and soil moisture retention curve in a part of the Hindon river catchment and studies the variation of these along the river in its upstream reach.

The study develops regional flood frequency relationship and flood formulae based on recently developed efficient techniques of flood frequency analysis to estimate floods of desired return periods for small to moderate size gauged and ungauged catchments of the middle Ganga plains (sub-zone 1F) encompassing parts of Uttar Pradesh, Bihar and West Bengal. A regional flood formula has been developed by coupling the L-moment based regional flood frequency relationship with the regional relationship between mean annual peak flood and the catchment area.

The study assesses the suitability of groundwater for drinking and irrigation use and examines the likely impact of Yamuna river water quality on groundwater. Delhi is faced with severe problems associated with groundwater quality and quantity. The quality varies spatially and seasonally, with depth and is primarily governed by the extent and composition of dissolved solids present in it. Surface water bodies play a role and the hydraulic gradient determines the lateral and vertical migration in the groundwater flow system.

Groundwater samples were collected through extensive field surveys covering entire Delhi area representing various geo-hydrological and land-use conditions. The data has been analysed with respect to BIS and WHO standards to examine its suitability for various uses. The area has a peculiar feature of infiltration of surface water to groundwater from river Yamuna and from various drains.