Abstract: In water resources and more specifically in hydrology, the application of mathematical models to represent the hydrological cycle process is crucial. This is the reason why the hydrological concepts are expressed in mathematical language to represent the corresponding behavior observed in nature. The current research targeted to development of a hydrological model using the HEC-HMS model for runoff estimation in Shetrunji River sub-Basin, India. The Soil Conservation Service-Curve Number (SCS-CN) Method was adopted to estimate the rainfall losses while the Soil Conservation Service-Curve Number (SCS-CN) Method was used to transform the excess rainfall into a direct runoff hydrograph. Muskingum Model was adopted for routing the total runoff from the outlet of the sub-basin to the outlet of the total basin. Model performance was achieved using different sets of data in which the data used was for Ten years (2013 to 2023). The regression analysis has been carried out for the comparison of modeled and observed datasets. The result of this research will help the global community in dealing with open-source data. It will enhance the decision-making system for un-gauged basins at a small scale level.

Keywords: HEC-HMS, Rainfall-Runoff Modelling, Shetrunji River Sub-basin, Regression Analysis

| DOI: 10.17148/IARJSET.2024.11427