The bachelor's thesis presents a theoretical overview of knowledge about Banská Štiavnica artificial water reservoirs - tajchs, the origin of which was related to the development of mining activities. The aim of the bachelor thesis was to determine the concentration of risk elements in the surface waters of Banská Štiavnica. In the years 2017 - 2019 (spring, autumn), surface water samples were taken from 8 tajchs: Dolný Hodrušský, Evička, Horný Hodrušský, Klinger, Rozgrund, Veľká Richňava, Veľká Vodárenská, Veľká Vindšachta. In the bachelor thesis, selected physical, physico-chemical and chemical parameters were analyzed: water temperature; water reaction (pH); specific conductivity and risk elements (As, Cd, Cu, Ni and Pb). In the first chapter, we described the risk elements (essential, non-essential) that affect the quality of tajchs and environmental and health risks. The chapter Methodology of work and research methods describes the character of the area, geological and hydrological conditions and characterizes the individual tajchs. We focused on the surface water sampling procedure and analytical methods used (water temperature, pH, conductivity and concentrations of risk elements). The values of concentrations of risk elements in surface waters of tajch were determined by atomic absorption spectrometry (F AAS and GT AAS). Based on the measured values of pH, conductivity and temperature, which we compared with the current legislation, we found that surface waters meet the criteria for water quality of class I, with the exception of surface water in tajchs Klinger (quality of class II). The analyzed risk elements As, Ni and Pb in tajch waters, met the criteria for class I for the quality of surface water according to the valid legislation. Water samples in which the risk elements Cd and Cu were analyzed were in some cases suited in IV. and V. water quality class depending on the place of extraction and period. With the achieved results, we wanted to contribute to the evaluation of the current state of artificial water reservoirs - Banskoštiavnické tajchs.