Numerical 2D-Modeling of Rain Runoff Transformation in the Drainage Basin of Gelendzhik City Taking into Account the Mountain Collector and Accumulating Reservoirs

A digital relief model of a mountain cluster and location schemes of mountain collectors and reservoir dams were used to develop a numerical hydrodynamic 2D-model of the mountain part of the drainage basin of Gelendzhik City area and to perform variant calculations of rain flood waves, taking into account their transformations in mountain collectors and accumulation in reservoirs. The rains considered in the model were assumed to have the exceedance probability of 1% and the duration of 20 and 720 min (12 h) with a total rainfall depths of 51 and 206 mm, respectively. Conclusions were made that the carrying capacity of the collector should be calculated for the parameters of a short-time intense rain and that the accumulating hydraulic structures, for their efficient operation, should be designed to allow continuous regulation of discharge rates.