ASSESSMENT OF THE DEFORMATION OF THE KRASNODAR RESERVOIR SHORES USING LASER SCANNING

Abstract

The Krasnodar Reservoir, located on the Kuban River, is a key element of the melioration complex in the south of Russia. The annual water intake for irrigation is about 3.35 billion m³. When commissioned in 1975, this valley reservoir had the projected area of 400 km². For over half a century of operation, its morphometric characteristics have undergone significant changes. An independent scientific and practical problem is the transformation of the shores, the impact of which on the change in hydrographic characteristics and general siltation of the reservoir remains insufficiently studied. The article presents the results of quantitative assessments of the shoreline abrasion and analysis of littoral processes based on multi-temporal lidar surveys (airborne laser scanning in 2019 and mobile laser scanning in 2023 and 2025). High-precision DEMs were constructed for test sections characterized by different relief formation settings. Monitoring of the Krasnodar Reservoir shoreline over a six-year period revealed considerable changes in the morphology of the shores. Significant volumes of shoreline abrasion were recorded on three key sections with a total length of 3.21 km: 54.3 thousand m3 with a total area of 8.9 thousand m2. At the same time, the rated average annual abrasion volumes for the entire reservoir (20.3 thousand m3) are incomparably less than the siltation volumes we have established (the average annual for 2005–2021 is 6.26 million m3). The highest activity of abrasion processes is noted on cliffs exposed to wave action. Here, a retreat of the shoreline by up to 57 m was noted, with the average retreat value for the studied shores equal to 2.9 m. The protruding of the Kuban River delta into the reservoir significantly changed the hydrodynamic regime of the littoral zone, reducing areas with intensive wave action. Changes also affected the beach area, where a gradual decrease in the height of shoreline ridges was observed over the period 2019–2023, this indicating the weakening of wave activity.