Horizontal displacements of rock foundations toward the lower pool are small and even for high (100 m and more) dams in narrow and wide sites do not exceed 15–20 m. Ths displacements rapidly die away with depth and at 10–15 m from the contact decrease by almost an order, and lower the displacements of rocks toward the upper pool as a consequence of deflection of the reservoir bed can predominate. Filling of the reservoir led to the divergence or convergence of the banks. In the majority of cases convergence was observed, including in the case of gently sloping banks. The movements affected points located more than 100 m into the banks.