Paper concerns the Włodzienin retention reservoir on river Troja located in Opole Province. Main function of this reservoir is flood protection and agricultural irrigatin. Reservoir capacity at NPP is equal 4 mln m3, and flood surface 86 ha. At present construction of this reservoir is near, and start of tankage is foreseen towards the end of current year. The authors presented on the paper prognosis of sediment inflow to reservoir. Calculations showed that this reservoir has been deposited after about 100 years. ...