Summary:

The balance of Dąbie Lake water has been analysed in three ways: as daily balance, averaged balance in a decade calculated on the basis of Regalica river flows determined by Mikulski and Ostapska-Bojanowicz (1965), and the water balance based on flows in water-courses reaching Dąbie lake, which has been determined using the model of lower Odra steady flow (Buchholz 1991). The method based on Odra river hydraulic model has turned out to be most important in the examination of Dąbie lake water balance. The share of Regalica river in the general inflow to the lake (calculated on the basis of this model) is 73,5%, (6557,8 millions m³), Orli Przesmyk canal has 23,9% (2135,3 millions m³), drainage area contribution is 2,3 % (205,5 millions m³) and precipitation brings 0.33% (29.3 millions m³). The outflow is shared by Iński Nurt canal (84%, 7503,2 millions m³), Babina (15,63%, 1395,5 millions m³) and evaporation – 0,33% (29,9 millions m³). Total inflow in the average year of multi-year period is 8927,9 millions m³ of water. On the basis on 1948-1990 period it has been calculated that on average 65 water exchanges take place in the lake yearly.