A study of static stress-strain state and dynamic behavior of earth hydro-technical structure (a dam) is carried out in the paper on the basis of two mutually orthogonal plane models. The study includes the structure together with surrounding rock base with weakened inclusion. Real geometry and heterogeneous physical and mechanical characteristics of soil in the dam body and foundation (presented by projecting organization) are taken into account. As a result of the research a number of offers-recommendations as to reliable and safe operation of earth dam are given.