Prioritization of sub-watershed using geospatial techniques and WSPM model in Mandakini River basin, Uttarakhand, India

The integrity of a watershed is majorly contributed by soil and water; those are essential to thrive sustainably in a hilly area like Uttarakhand. With geoinformatics techniques mapping and estimation of hazard-prone areas can be done. The current study is based on the prioritization of sub-watersheds (SW) by using a correlation-based approach named the weighted sum priority model (WSPM) by utilizing Cartosat DEM. The Mandakini River Basin was delineated into 5 major sub-watersheds to study morphometric attributes, i.e., linear, areal, and relief parameters. The mean estimation of drainage density (Dd) is 2.51 and Stream frequency (Fs) is 4.46. Fs and Dd show positive correlation with other linear and areal parameters (0.83). Elongation Ratio (Re) values for SW 01 and SW05 shows oval shape of sub-watershed. The Form factor (Ff) value of SW 04 featuring a gradual rise and prolonged flow. The cumulative rank for all SW has been computed using the WSPM model, reveals the SW3 and SW4 have the highest priorities for soil erosion among all the rest of the sub-watersheds. This comparative study approaches planners and government officials to assist in decision-making for erosion conservation structures and also in the prediction of hazard-susceptible zones.