Hydrologic and Cost–Benefit Analysis of Multiple Check Dams in Catchments of Ephemeral Streams, Rajasthan, India

Investment in the small-scale enhancement of groundwater recharge through check dams and other structures rural India is on order USD 1 billion/year. However, for any catchment, optimal capacity unknown, impacts downstream flows are rarely determined. This paper describes a method that can be applied to plan augmentation catchments have at least one monitored dam. It was Dharta catchment Aravalli Hills Udaipur district, Rajasthan, India, where four an ephemeral stream were by farmers over seven years. For last three years this study, hydrology two these affected 19 new established upstream. A basic hydrologic model, WaterCress, calibrated check-dam storages used assess from those downstream. Then, model rerun with range capacities upstream determine effects (1) dam, (2) total all dams, (3) frequency spill Using available economic information, benefit–cost ratio calculated capacities. showed decline efficiency each dam defined capacity. Monsoon size found consequential results, longer hydrological records yield more reliable results. The study monitoring rainfall, levels key deciding whether additional economically beneficial.