Utility of Normalized Difference Water Index and GIS for Mapping Surface Water Dynamics in Sub-Upper Krishna Basin

Mapping of the surface water dynamics in parts of Upper Krishna River basin, Maharashtra State of India, was attempted in this study. It comprises an upland watershed and a major tributary of Krishna River in the Upper Krishna basin. Keeping in view that it is essential to appraise the accessibility of surface water in a basin containing the non-perennial river to deal with the water resource management, the present study area was chosen for investigations. This study modelled the surface water dynamics of the Sub-upper Krishna basin (SUKB) over a period of 17 years from 1999 to 2016 with cloud-free Landsat data sets. The technique of normalized difference water index (NDWI) was used to detect the surface water bodies of the basin. The NDWI-generated images were classified into water and non-water pixels, and an accuracy assessment was performed to find out producer’s, user’s, and overall accuracies of output. The NDWI method displays a good result of water surface detection with a Kappa coefficient ranging from 0.81 to 1.00 for the classified images. The surface water-mapped images were used to classify the water into permanent water, seasonal water and new permanent water. The change detection is performed and mapped using geographic information system (GIS) operations to understand the surface water dynamics from 1999 to 2016. The results illustrated the effectiveness of the NDWI approach for surface water mapping and GIS for change detection analysis, especially in detecting the changes in different times, simultaneously.