The design is considered, involving the use of instrumental and analytical apparatus of GIS (geographic information systems) in order to provide monitoring and support for decision-making by government authorities. For these purposes, the basic models and methods for solving problems that arise before the administration of governing bodies have been analyzed. The design of a graphical-analytical model of a thematic layer of an electronic GIS map using a quadratomic tree is also described. A graph of conceptual-meaningful features and a graph diagram of the formation of graphic means for the design of signs are considered. The advantages and disadvantages of the quadratic tree model are described. In addition, the assessment of the temporal and capacitive complexity of information extraction, which is the main component of clarifying a clear algorithm for setting the problem during the functioning of the system being developed, is analyzed.