Abstract
Physico-chemical variables of water quality and benthic community structure were assessed in order to evaluate the need for reinstating the use of the preliminary Jedlice Reservoir. The waters of the Mała Panew River carry a significant load of nutrient compounds, particularly nitrates and phosphates. Deteriorating water quality results in permanent algal blooms and changes in the macrofauna structure. It was confirmed that the use of a preliminary reservoir could contribute to the protection of the Turawa Dam Reservoir against pollutants transported by the waters of the Mała Panew River.