Development of Complex GIS Monitoring of the Angara River

This work is devoted to development of hybrid geoinformation system for making forecasts of areas of possible flooding in the downstream water of Irkutsk hydroelectric station with damages evaluation in conditions of extreme water content for lake Baikal and for effluents of the Angara river. For 3D model construction of the Angara’s bed they used Atlas “Map of the Angara River in Irkutsk hydroelectric power station up to 142 km on scale of 1: 10000” General plan of “Waterways of the East Siberian basin”, Irkutsk, 1994. Due to lack of a digital model (map), a paper-based map was digitized using vectorizer program Easy Trace 7.99. Depth contours, marks and bank lines were also digitized. To combine the data about land and underwater terrain a specific software was developed using Delaunay triangulation method. For data layers their role in the construction of triangulation is specified. The layers contain information about: land relief, standing water levels, shore lines, underwater topography. To work with the underwater terrain information about standing water levels is used. Auxiliary triangulation is made according to the data whereof further information is revealed regarding heights levels to which shore contours are attached and in reference to which depths are measured.