Methodological Approach to Optimization of the Precipitation Estimated Frequency

While designing drainage systems and storm water drainage networks, the estimated frequency of the intensity of atmospheric precipitation are assumed empirically, taking into consideration years-long operation of such structures. The issue of determination of the estimated frequency of the atmospheric precipitations’ intensity, based on the objective criteria, is reviewed in the article. For the settlements chosen at random (three for drainage networks and three for the storm water drainage network), with different characters of the curve of the estimated frequency of precipitation intensity, calculation was carried out and the unitary cost was determined. Based on these data the graphs of the precipitation dependence of the intensity on the frequency and dependence of the unitary price on the intensity of precipitations are plotted. Combination of the graphs gives the estimated value of frequency.