The relevance. The problems of the cryolithozone territories are related to the wide development and activity of thermal erosion, thermokarst and other cryogenic processes. On one of the sections of the route of the water main «Lena–Myuryu» in Central Yakutia the danger occurs. It has negative impact on stability of the pipeline. Man-made cryogenic processes (thermokarst, thermal erosion, etc.) on the scale and consequences bring great material and economic damage to the main water pipeline and road maintenance. Why anthropogenic? Because the main factor – technogenic-cutting of the surface layer by earthmoving machinery. The main aim of the research is to identify and disclose the causes of natural hazards of cryogenic processes (thermokarst and thermal erosion) on the route of the main water pipeline. The object of the study is the geocryological environment considered in operation of the section of the main water conduit «Syrdah–Borogontsy» in Central Yakutia. Methods: field route observations, simple empirical studies (observation, description, measurement) and some types of engineering-geological surveys. The study of archival materials and the latest information allowed tracing the development of cryogenic processes in dynamics. Results. At detection and disclosure of the reasons of thermal erosion on the route of the water main the factors of its formation were determined and its map chart was made. The author has identified and characterized the places with natural hazards from the influence of cryogenic processes. The geocryological conditions of the territory are favorable for development of thermokarst and thermal erosion, but the key factor is technogenic-pruning of the soil and vegetation layer, the presence of the ice complex, including the upper Quaternary deposits of sandy loams and silty sands, as well as the flooding of thermokarst basins.