The Krasnodar Reservoir on the Kuban River is the most important object of the reclamation system in southern Russia, with an annual water intake for irrigation of 3.35 billion m3. The valley reservoir is located on the Azov-Kuban Plain and has an area of 400 km2 according to operational characteristics. It has been in operation since 1973. As a result of continuous transformation (siltation, eutrophication, etc.), the hydrographic characteristics of the reservoir are changing. The study is aimed at experimentally confirming the applicability of laser scanning methods for quantitative assessment of coast processing and obtaining quantitative data on the dynamics of the shores of the Krasnodar Reservoir based on the results of repetitive lidar surveys. The processes of coast transformation and their participation in siltation and changes in hydrographic characteristics (area, useful volume of the reservoir) are still insufficiently studied. A repeated lidar survey was used for the first time to analyze the coast transformation, carried out in 2019 (airborne laser scanning) and 2023 (mobile laser scanning). Based on the lidar survey data, high-precision digital models were built for the selected test coastal sites with different types of morpholithogenesis (active cliff, dying cliff). The total length of the three studied coast sections was 3.21 km. The point cloud sets at different times made it possible to differentially determine the linear displacement of the cliffline and the volume of coastal destruction for 2019–2023 according to 58 blocks (three-dimensional units enclosed between two DEMs). Abrasion volumes per 1 linear meter varied from 0.4 to 99.9 m3/m with an average value of 12.4 m3/m. The total volume of coastal destruction in an area of 7.3 thousand m2 during the study period amounted to 44.8 thousand m3. The retreat of the cliffline in different sections of the coast varied from 0 to 54.5 m. For the first time, the results of high-precision instrumental measurements give an idea of the dynamics of the banks, as well as the contribution of bank destruction to the siltation of the Krasnodar Reservoir. The proposed survey and analysis methods bring reservoir monitoring to a new technological level. Accurate estimates of siltation volumes and changes in the hydrographic characteristics of the reservoir are necessary to develop a sound long-term strategy for the use of water resources in the semiarid region of Russia.