Modern technologies give an opportunity to create a large number of bathymetric maps, but less of them have been focused on processing the water depth data in order to study and estimate the subterranean sources of water object supply. This study aims to create a mechanism for estimating the productivity of subterranean sources of lakes water supply, based on bathymetric survey data. Lake Svitiaz was chosen as the study site as the deepest closed lake of natural origin in Ukraine with an area of 2500 ha and a maximum depth of 58.4 m. To get depth data, ground-based measurements were conducted using an echosounder Lowrance LMS-527cDF. The Lake morphometric changes were investigated, using bathymetric data and Sentinel A, and B data in the digital elevation model (15×15 m). Bathygrahic analysis was performed, allowing selecting areas for further echo-sounding, taking into account complex relief and specific basin forms of the Lake. To develop an appropriate technique for estimating the productivity of subterranean water supply sources, GIS and image (echogram) processing techniques were applied. The research tasks are completed as a technique for detecting ‘tracks’ and a mechanism that is quite effective, particularly for early evaluation of subterranean sources of water supply productivity that can be repeated on any similar water objects.