ABSTRACT: This article presents the results of 2010 - 2014 monitoring of δ18O and δ2H in weekly samples from two surface water sites and three springs. In addition, the water chemical composition in three springs and at six stream sites was determined monthly from December 2013 to November 2014. The isotopic composition of the springs was identical in all the different geological settings (crystalline rocks, alluvial fan and Jalovecký creek alluvium. The Jalovecký creek water sampled at the outlet of the mountain part of the catchment originates at altitudes above 1000 m a. s. l. and the δ18O - δ2H relationship and higher deuterium excess suggest that precipitation from the lower altitudes of the mountain part of the Jalovecký creek catchment is the source of water for all springs. The isotopic similarity of stream water near the outlet of the entire catchment and the springs indicates a higher proportion of groundwater in the Jalovecký creek in the foothill part of the catchment. The springs’ specific electrical conductivity and isotopic composition indicate mobilization of water with longer transit time at the beginning of the snowmelt periods. Concentrations of manganese, sulphates, chloride and calcium at stream sites located in the Liptovská kotlina valley (i.e. the Jalovecký creek at the outlet of entire catchment and the Váh River in Liptovský Mikuláš) are higher than at sites located in the mountain part of the catchment. Seasonal changes in stream ion concentrations were at monthly time step of sampling noted only for nitrates and sulphates in the streams.