Paper Details

Spatial and temporal runoff measurements are required for planning, developing and managing awatershed sustainably. Among the methods for estimating runoff from rainfall, the SCS (NRCS)-CN method is mostused practical method due to its requirement of single parameter estimation called Curve Number (CN). In the presentstudy, the runoff from the upper Manimuktha sub-watershed (4C1A2e), an ungauged watershed in Villupuram districtof Tamilnadu, India, has been assessed. IRS 1C LISS-3 satellite images (1995, 2003 and 2012) were used to obtainland use/land cover information. Hydrologic Soil Groups (HSG) map was prepared from the soil map of the study area.After integrating land use/land cover and hydrologic soil layers, weighted curve numbers were obtained and mappedby using ArcGIS 10.5 software. The daily rainfall data were collected from Gomukhi dam and Manimuktha damraingauge stations for 25 years (1992-2017) and converted to weighted spatial distributed rainfall by Thiessen polygonmethod and used to calculate the daily, monthly and annual runoff. The average annual minimum and maximumrainfall were 548.23mm (in 2016-2017) and 2151.61 mm (in 2005-2006) and the corresponding runoff were 64.28mm(in 2016-2017) and 1134.02 mm (in 2005-2006). This study will be useful to estimate runoff from an ungaugedwatershed having same characteristics.

Velayudha Das M, Poongothai S, “Estimation of Surface Runoff Using GIS-Based NRCS-CN Method in Upper Manimuktha Subwatershed,Tamilnadu,India”, International Journal of Advance Engineering and Research Development (IJAERD), Vol. 5, Issue 3, pp. 68-79, March 2018.