Groundwater is one of the world's most precious natural resources. But still now this valuable resource is largely unexploited for agricultural development in drought prone western region of West Bengal. In drought prone areas micro-watershed based development strategy may be considered as the best practice for integrated development. Keeping in view the above perspective, we select Kumari watershed of Purulia district, the westernmost and semi-arid district of West Bengal for better water resource management. Geologically the area consists of Chotanagpur granite gneiss complex while physiographically it is highly dissected pedimental landscape with lateritic upland and skeletal soil. As a result, cultivation of this area is predominantly mono-cropped and thus per hectare production is also low as compared to other regions of West Bengal. Supply of sufficient water resource in this region may offer more food security alternative to rain-fed subsistence farming. That's why the present study has been carried out to evaluate the potential zones for groundwater targeting in Kumari watershed of Purulia district using an integrated remote sensing data, Survey of India topographical sheets and field verification. Hydro-geological features (geomorphological and geological units, slope, drainage density, lineaments density etc.) that influence groundwater occurrence were extracted and integrated to evaluate the hydro-geomorphological characteristics of the study area. Thematic maps of the extracted features were prepared with the help of ERDAS Imagine 9.0 and Arc-GIS 9.3 software. Weightage values were assigned to the different parameters according to their relative importance to groundwater potentiality and integrated through Geographic Information System environment. Finally on the basis of grid-wise theme weight and class weights the groundwater potential map was prepared by overlay the thematic layers.

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Estimation of flood intensity for a desired return period is of prime importance for flood management through flood plain zoning. Flood frequency analysis enables estimation of the probability of occurrence of a certain hydrological event of practical importance by fitting a probability distribution to one that is empirically obtained from recorded annual maximum discharge and/or stage data. This case study considers the use of four probability distributions, namely Gumbel's extreme value distribution (EV-I), extreme value distribution-III (EV-III), log-normal (LN) and Log-Pearson Type III (LPT-3) in flood modelling of monsoon-dominated Ajay River and illustrates the applicability of goodness of fit (GOF) and D-index tests procedures in identifying which distributional model is best for the specific data. Twenty-five years ) of existing and estimated annual peak discharge (Q max ) data have been used for analyzing the trend of flood occurrence. After identifying the best fit model, the peak gauge height data (h max ) are then analysed combining with geographic information systems (GIS) for predicting flood affected area and preparing inundation map at a specific return period (T). Results of the study showed that the LPT-3 distribution is better suited for modelling flood data for Ajay at Nutanhat in West Bengal. The computed Q max for LPT-3 distribution are slightly higher as compared to the results obtained by EV-I, EV-III and LN which are used for vulnerability assessment. The analysis also predicts that the affected area will be ranging from 235 to 290 km 2 in near future (at 25-to 200-year T). These findings provide clear picture for the pattern of hydrological fluxes and aftermath in the next decades in lower Ajay River Basin (ARB). Sustainable planning and developmental measures that consider the modelled pattern of hydrological fluxes of the study area were recommended for decision making.