65% of the drinking water in Ostrava is treated surface water from dammed reservoirs in the wider region, supplied via the regional water main network. The remaining 35% of supplies are groundwater. The main sources are the reservoirs at Šance, Moravka and Kružberk. Water from these reservoirs is treated before being supplied to consumers. Ostrava’s drinking water meets all legislative quality and hygiene standards.
Out of the 300 700 inhabitants connected to the public water supply system (2016), over two-fifths are supplied with groundwater. The annual production of drinking water from groundwater sources fluctuates between 5.9 and 7.5 million m3. Due to its optimum mineral content, the water from these sources represents a valuable addition to the water from surface sources. The location of groundwater sources minimizes distances to end users and ensures that essential drinking water can be supplied quickly in emergency situations. Groundwater is extracted in a sustainable manner in order to ensure that this renewable resource remains available on a long-term basis.