A study of the quality of drinking water (spring and centralized water supply) was conducted. Determination of water hardness and alkalinity was carried out by titrimetric analysis methods in a chemical laboratory. The dependence of these parameters in the autumn and spring period is established. The limits of changes in water hardness values are 3.4-9.9 mmol / l in autumn, 3.2-9.8 mmol / l in spring. Most of the studied natural waters are of medium hardness and hard water, therefore, there is a need for water softening. The limits of change in the alkalinity of water are 0.6 - 5.1 mmol / l in autumn, 0.8-5.3 mmol / l in spring. The alkalinity values of all samples are within the limits of the MPC norms. A comparative analysis of the results of the study is carried out, which establishes the dependence of the hardness and alkalinity of water in different seasons. The values of water hardness decrease during the flood, while the values of alkalinity increase during this period. It is recommended to conduct further research in order to determine the feasibility of using water softening methods for objects where water has high hardness values, and to choose the optimal softening methods.
Keywords: alkalinity, hardness, methods of titrimetric analysis, natural water, softening, autumn period, spring period