Water as the most widespread liquid on Earth is the source of life. Water is also the most important solvent. The proportion of water in the human body depends on the age of the organism, and on average ranges from 75% in newborns, to 50% in the body of the elderly. Throughout history, cultures have changed, lifestyles have changed, but man’s need for water has remained the same. Every great civilization began its life by the water, river, or seashore. Water from rivers was used to irrigate agricultural goods, but certainly also for drinking. Water is a chemical compound of one oxygen atom and two hydrogen atoms, and is present on Earth in the form of fresh and salt water. Water for human consumption must be clear and completely transparent, without color and odor. The drinkability of water is conditioned by the presence of a number of chemical compounds in the water where the presence of carbon dioxide, dissolved oxygen, and soluble mineral salts (sodium chloride and sodium bicarbonate) is one of the basic prerequisites for good and acceptable water taste. Croatia is at the very top in terms of the amount of water in Europe and in the world. The Slavonia-srijem depression, located in the area of the former Pannonian Basin, abounds in high-quality groundwater. In the Brod-Posavina County, there is the municipality of Sikirevci, where the water pumping station "Eastern Slavonia" is located, which, according to experts, lies on the richest aquifer in Croatia. There, water from 8 wells is pumped from 80 meters below the surface. Of these, water from 4 wells is supplied to the city of Slavonski Brod, while water from 4 wells is pumped for the needs of the water supply system of the city of Vinkovci and surrounding settlements. In order to distribute healthy water, water quality is determined by analyzing water samples from wells and analyzing water samples from the water supply network. Healthy water must meet the Ordinance on compliance parameters, methods of analysis, monitoring and water safety plans for human consumption and the manner of keeping the register of legal entities performing the activity of public water supply (NN 125/2017, 39/2020).