Soil erosion in relation to rainfall characteristics in small watersheds in Shivalik foothills

The data on rainfall, runoff and soil loss was collected in two small watersheds, namely WM-I and WM-II at Mansa Devi in district Panchkula, in fragile North-Western Shivalik foothills of Haryana. Based on ten years data the percentage of rainfall received during monsoon period to annual rainfall was as low as 58% to as high as 92%. Annual rainfall erosivity varied from 570 to 1561. Relationship of rainfall characteristics, runoff and sediment yield of fifteen individual storms (during 1998–2002) were analyzed. Rainfall amount of individual storms varied from 14.5 to 109.8 mm with average intensities 10.0 to 60.0 mm hr⁻¹ and kinetic energy 331.1 to 2806.7 mt per ha - cm. Maximum 5 minutes intensities varied from 38 to 144 mm hr⁻¹. Whereas, maximum 10, 15 and 30 minutes intensities were always less than 5 minutes intensity. Rainfall erosivity considering 5 and 10 minutes maximum intensities, i.e. EI₅, and EI₁₀ were found to be a better predictor of runoff and sediment loss estimation in small watersheds of north-western Shivalik foothills.