Prioritization of watershed using morphometric parameters through geospatial and PCA technique for Noyyal River Basin, Tamil Nadu, India

Watershed management is essential for ensuring the availability of water for sustainable development. In the current study, the geospatial technique is utilized to prioritize the sub-watershed of the Noyyal River Basin to control soil erosion and propose water conservation measures. The study describes the importance of using a digital elevation model to evaluate the drainage pattern and to extract relevant parameters. The river basin was categorized into 17 sub-watersheds, designated as SW1-SW17. The stream order of watershed ranges between first and fifth order and possesses a dendritic drainage pattern. Thirteen fundamental morphometric parameters classified as linear, areal, and relief aspects were considered for the Noyyal River Basin. The principal component analysis (PCA) was performed in the current study for categorization and the morphometric parameters were correlated. PCA analysis is a more appropriate, well-known, commonly used method for having versatility in selecting more significant parameters (correlated parameters) that are responsible for watershed prioritization. The sub-watershed with the lowest compound value is ranked first in the priority. It reveals that sub-watershed SW8 has a high priority while low priority is given to sub-watershed SW17. According to the results, more water and soil-conserving measures are suggested in the respective sub-watershed.