Assessment of hydrological behavioural changes of Noyyal watershed in Coimbatore district, India by using SWAT model

Abstract

The study aims to assess the hydrological behavioural changes of the Noyyal watershed, using the SWAT model. The SWAT model was used to stimulate a total of 15 years' of information on factors including rainfall, temperature, relative humidity, wind speed, and solar radiation. It was chose to study the Uncertainty Fitting procedure (SUFI-2) as the model for sensitivity analysis, calibration, and validation. The hydrological activity models were used with DEM, LULC data, soil, and climatological data for both types of sensitivity analyses, such as one-at-a-time and global sensitivity analysis. In this study, stream flow and sediment yield were calibrated and validated on a monthly basis. Calibration began over a 12-year period from 2003 to 2014, while validation actually occurred over a four-year period from 2011 to 2014. PBIAS, NSE, PSR, and R2 statistical indices show the model performs “excellently” at simulating hydrology. In comparison to the various automatic calibration techniques, SUFI-2 was observed to be very acceptable and simple to use. The hydrological behaviour of the Noyyal watershed has changed dramatically over the last two decades.