Based on extreme water levels data, using the method of series, a forecast for protection of river has been accomplished, i.e. probable water level maximums of the Đetinja river at Šengolj were measured. High flows were analyzed with a probability from 0.01% to 99.9%. These probabilities indicate the occurrence of high flows of certain values once in 10.000, 1.000, 100, 33, 20 etc years. Applying a hydrological forecast, one can perceive the possibility for using water resources for various purposes, as well as protection of areas and people from flooding. A review of the greatest floods in the Đetinja drainage basin in the last hundred years is given in this paper. .