Symulacja wpływu oczyszczalni ścieków w Myślenicach na eutrofizację wód zbiornika "Dobczyce"

There are five independent municipal water supply systems in Cracow. Four of them make use of riverine water intakes (on the Raba, Rudawa, the Dłubnia and the Sanka) and one draws underground water (Mistrzowice intake). Of these, the Dobczyce reservoir on the Rawa river is the main contributing source of the water supply system, covering 52% of the average daily demand. In extremities, the intake is able to cover 67.6% of the total demand. Because of its contribution, the water supply system which involves the Dobczyce intake must be of high reliability. In general, the supply system meets the reliability requirement, owing to the failure-free operation of the intake and of the water treatment plant in Dobczyce. Yet, there is periodical blooming, which deteriorates the quality of the taken in water. In the present paper, the main pollution sources are characterized and the quality of the reservoir water is assessed. Making use of the American software WASP4, the eutrophication of the Dobczyce reservoir due to the maloperation of the Sewage Treatment Plant in Myślenice was simulated. The simulation made it possible to estimate the phenomena involved and to determine the adverse effects of water quality variations.