Many theses produced in the Gdańsk Environmental Education College are based on research work. The author focuses on the one such study on water quality in the Gdańsk Old Town centre. The thesis aims at determining the level of surface water pollution, with special focus on industrial impacts. Physical and chemical measurements gathered from six stations in the course of November, January and March included a wide spectrum of pollutants. The author discusses the study in detail. It can be concluded generally that the water of the Motława, Stara and Nowa Motława Rivers and Na Stępce channel are within III water purity class.