This research is a part of the Project entitled “Creating of hydrogeological model of Latvia to be used for management of groundwater resources and for evaluation of their recovery measures”. It is supported by the European Regional Development Fund. In the hydrogeological model (HM) the ground relief will be used as the boundary condition. In this article, problems and solutions are described of incorporation of hydrographic network (HN) into the digital relief map. The software that automatizes the process of incorporation is described. The algorithm for creating new points of river profile line is described.