The study discusses the hydrological aspects of rainwater harvesting in the Kandi belt in the foothill zone of Siwalik in Jammu region with the help of a case study on water availability in a pond in village Badhori (Samba district, Jammu). It describes the climate, soils, geology, geomorphology and drainage of the Kandi belt. It is marked with small watersheds having low denuded hills and undulating cultivated lands that need to be developed on a watershed basis through engineering and non-engineering measures of rainwater harvesting and soil conservation.
There are numerous big gullies and ephemeral streams originating from low hills and flowing into cultivated terrains. In the hilly upper portion of the catchments, their cross-sectional area increases progressively towards the flow direction. Horse-shoe type watersheds all along the Siwalik hills provide a good site for constructing small water harvesting structures. Springs or baolis are absent in the area, while ponds are common and used to be the main source of drinking water till the 1960’s.
For the most part, ponds were designed to collect a part of the runoff and helped reduce erosion and downstream floods apart from improving groundwater. Over the years, the design of ponds, stone pitching of their berms, and the role of clay in checking heavy seepage in the highly porous Kandi belt evolved. The study suggests a sound scheme for rejuvenating village ponds using inputs from hydrology, geology, geophysics and soil sciences.
The study looks at design parameters like water yield, peak discharge, storage capacity, dam height, spillway, precipitation and runoff. It presents the rainfall-runoff relationship in Siwalik region through a table, which indicates runoff as a proportion of rainfall, for different land use and management practices. Water inflow to the pond was evaluated on a monthly basis. Although the capacity of the pond is quite large, the present analysis shows that only about one-third capacity is utilized under the prevailing climatic and soil conditions. If through suitable measures, evaporation and other losses are reduced, more water will be available for local consumption, and the available capacity of the pond water can be successfully used for cattle and horticultural purposes.
Download the report here: