Evaluation of Hydro-Meteorological Conditions at the Water Reservoir for Supply of Drinking Water in the Period Since its Commissioning

Safe drinking water and its abundance include into among the basic attributes of a healthy environment and the basic human rights. As climate change progresses, ensuring a supply of drinking water to the population will pose increasing challenges. In this context, apart from exploiting groundwater sources, water reservoirs will assume a pivotal role in addressing this issue. On the territory of the Slovakia, there are currently 8 water reservoirs, which are used to collect water for the production of drinking water. One of them is the Turček reservoir, which was completed in May 1996 and has been in full operation since 1997. In this contribution, the hydro-meteorological data from the Turček water reservoir location, which were provided by the operator of this reservoir, are evaluated. These data contain information on daily values of basic characteristics. The period 1997-2021 was analyzed, especially the development and trends of precipitation, air temperature, occurrence of a given type of weather during this period and ice cover thickness and duration. The analysis of hydro-meteorological data showed that the average annual air temperature is rising slightly, for the period 1997-2021 it rose by 0,03 °C. The ice cover thickness (both maximum and average value) shows a decreasing trend and decreased by 7,3 cm during the observed period. The same trend is shown by the duration of the ice cover on the reservoir surface. The frequency of precipitation events has been decreasing for a long time, the annual total depth of precipitation also has a decreasing trend. Recently, this reservoir also had a problem with the occurrence of cryophilic cyanobacteria, the occurrence of which is not desirable in such types of water bodies. The performed analysis of the development of hydro-meteorological conditions is an important basis for the evaluation and understanding of processes related to water quality in this reservoir.