GIS in hydrology of Lublin

Abstract

The aim of this paper is to present the method of determining urban catchment on the example of Lublin, the determination of the basic topographical and hydrological parameters conditioning formation of surface runoff and drainage during heavy rains and to create and test a simple hydrological model, sufficient for determining the volume of outflow from each catchment with assumed amount of precipitation caused by summer rain storms. Calculation of the amount of rain water flowing out from the city allows also to estimate pollutant loads and their run-off routes into the river system.
To determine the volume of water involved in the outflow SCS CN method (Soil Conservation Service Curve Number method) was selected. This method is developed by the U.S. Natural Resources Conservation Service. To describe the elements of the environment which determine hydrologic phenomena, spatial data from different sources were used. Spatial data were integrated in one database. To the information layer describing the land use, array of values of average concentrations of pollutants was included. The modeling results were confirmed by observations in experimental catchments.
Calculations were performed using ArcGIS software, with Spatial Analyst and Hydrologic Modeling extensions. Also, L-Thia GIS software was used to determine the parameters of CN, effective precipitation and outflow volumes.