Identifying and protecting natural resources is a meaningful way forward for achieving sustainable development. Since water is a precious natural resource that is being depleted faster than it is recharged, there is an urgent need to evaluate and monitor this resource. Watershed-based studies are gaining momentum, while studying about the natural resources. The purpose of this study is to analyze the morphometric characteristics of a watershed. Numerous morphometric parameters have been devised by various scholars to measure the drainage basin characteristics quantitatively. The methodology of this study is to make use of remote sensing and GIS techniques to analyze the drainage morphometry of Vannathangarai watershed in Tamil Nadu, India. The study has identified that the watershed has a low runoff and slow infiltration, thus pointing toward a probability of flooding. The study also revealed that the basin is well drained, basin where the surface is lowered by erosion.

Aims: The paper aims to study about the river basin morphometry namely the physical, linear and aerial parameters for the basin. Study Design: The Study has been carried out with the help of Geospatial techniques and statistical formulas. Place and Duration of Study: Bharathapuzha river basin, Kerala, India between January 2018 to July 2018. Methodology: The Study of River morphometry of Bharathapuzha River basin has been done with the help of SRTM satellite data. The downloaded data has been analyzed with the help of ARC GIS Software. The morphometric analysis has been carried out by dividing the basin into nine watersheds based on Water shed Atlas of India Prepared by Soil and Land Use board of           India. Relief, Linear and areal parameters of the basin is calculated with the help of statistical formulas. Results: Based on the analysis it is noted that there is not much difference in morphometric values except in some watersheds. Watershed number 5A2B5, 5A2B6 and 5A2B7 has highest drainage density, stream frequency, relief, relief ratio, ruggedness number, stream length ratio and lowest bifurcation ratio. These watersheds are characterized by highest surface runoff and erosion. The values of form factor, circulatory ratio and elongation ratio suggests that most of the watersheds are elongated and has high basin relief. The maximum stream order frequency is observed in case of first order streams and then for second order streams. Hence it is noted that there is decrease in stream frequency as stream order increases. Conclusion: The mean bifurcation ratio of the Bharathapuza basin is 1.52 which indicates the whole basin is less effected by structural control. This present study is valuable for the erosion control, watershed management, land and water resource planning and future prospective related to runoff study.

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Rainfall constitutes an essential component of the water cycle and is the prime source of groundwater recharge. In recent decades, groundwater exploitation has significantly increased, particularly for agricultural purposes, because large parts of the country have little access to rainfall due to frequent monsoon failures. In this context, an attempt is made to study the rainfall variability trend analysis. The study area selected for the research is the Vannathangarai watershed of the River Noyyal basin, the tributary of River Cauvery in South India. Rainfall data for 33 years were collected from 12 rain gauge stations in and around the watershed. The study explores the trends of rainfall, its variability, and the connection between rainfall intensity and the number of rain days. It is evident from the current analysis that October is the rainiest month, and the North-Western monsoon provides maximum rainfall. South West monsoon rains are highly variable than all other seasons. The western region receives the maximum rainfall than all other areas.