Abstract
The paper presents a case study for the evaluation and comparison of three calculation methods in terms of taking the water flows resulting from storms and after melting snow for a metropolitan area, whose rainwater catchment system is the most often completely over run, with frequent flooding in the area. The study compares the results of three calculation methods by correlating the relationships and values used in the literature with the real situation determined on several calculation sections, on different water courses in the proposed area. Based on comparisons for the obtained results, the paper presents a series of conclusions that could be useful in urban systems projects.