Ostrava - where does drinking water flow to households and where does it end?

Another city we focused on in our journey along the path of drinking water in the big cities of the Czech Republic is Ostrava, a city of 290,000. Water consumption in this Moravian-Silesian metropolis is 97 l/day/person, which is only slightly higher than the national average. Interestingly, over half of the water consumed by households in Ostrava comes from underground sources, taken directly under the city. What are the other sources of drinking water for Ostrava? How difficult is the water's journey to households? Where is it purified and where does it ultimately end up?

In the Moravian-Silesian Region, the Ostrava Regional Waterworks operates as the basic system for the production and supply of drinking water. For Ostrava, drinking water is produced from surface water by two of the three water treatment plants connected to it - ÚV Nová Ves and ÚV Podhradí. They cover 60-65% of the drinking water supply to the regional city.⁽¹⁾

ÚV Nová Ves - engine room
source: www.ovak.cz

ÚV Nová Ves - filtration
source: www.ovak.cz

ÚV Nová Ves -building
source: www.ovak.c

The remaining approximately one third of the drinking water produced for Ostrava comes from underground sources directly in the city area. Thanks to them, the transport distance and transport time between the source and the consumer is minimised. Water from the Dubí and Nová Ves springs has been treated in the Ostrava-Nová Ves waterworks since 1908. It is the largest and most important water treatment plant in the city.⁽²⁾ Its importance is also reflected in the fact that the area of the treatment plant became a protected monument in 2008 and, together with the two springs, was designated as a strategic resource by the Ostrava City Council in the same year.⁽³⁾Underground water sources in Ostrava fall within the protective sanitary zones. Moreover, due to the industrial and mining nature of the city, they are frequently tested for possible pollution.⁽⁴⁾

One of the surface water sources is the Šance dam on the Ostravice River in the Beskydy Mountains. This water reservoir, which falls within the protective sanitary zone, was built between 1964 and 1969 due to the growing demand for drinking water in the Ostrava region. During its construction, the centre of the village of Staré Hamry was flooded, which caused a significant reduction in the number of inhabitants there.⁽⁵⁾ The waterworks, from which drinking water is distributed to Frýdek-Místek, Karviná, Nová Ves, Nováčín, Ostrava and the Polish border region, is 70% self-sufficient in electricity consumption thanks to a small hydroelectric power plant on the raw water intake from the dam.⁽⁶⁾

Švanec Dam
source: infocentrumostravice.cz

The Kružberk reservoir
source: pod.cz

The second of the mentioned water treatment plants, ÚV Podhradí near Vítkov, takes water from the Kružberk reservoir on the Moravice River in the Jeseníky Mountains. The hydroelectric power plant built in 2014 completely covers the electricity consumption of this waterworks, which has been producing water for Ostrava for more than 60 years. The water treatment plant building itself is an example of industrial architecture by the architect Kainar. Its façade is also decorated with a monumental work by the national artist Vincenzo Makovský.⁽⁷⁾

Emphasis is also placed on replenishment of spring water, with the main aim of enabling the sustainable use of this source of drinking water. As part of water conservation measures, efforts are also being made to reduce water losses in pipes, which accounted for almost 13% of the total in 2016 ⁽⁸⁾.

Ostrava Waterworks and Sewerage Company operates a total of 5 wastewater treatment plants in the city.However, 98.7% of treated wastewater passes through the Central Wastewater Treatment Plant Ostrava-Privoz. It replaced the outdated and overloaded treatment plants in Přívoz, Třebovice and Zábřeh in 1996. In addition to the water discharged from households, concentrated wastewater from the coke and heating industry is treated here, which in 2016 was treated over 530,000 m3.

ÚČOV Ostrava-Přívoz
source: www.ovak.cz

Although the majority of the inhabitants of Ostrava and the surrounding area are connected to a single sewerage system, or separate ones often built in housing estates, there are areas in the outskirts and inner parts of the city that are connected to septic tanks. However, this system of septic tanks is gradually being dismantled ⁽¹⁰⁾.

After twenty years, the construction of a unique waste tunnel of the new sewage collection system, which was created by blasting, a classic mining method, was completed this February. The construction of the 671 metre long tunnel proceeded at a rate of 1.5m per day at a maximum depth of 28 metres below the surface. The sewer will be used mainly for sewage disposal in the towns of Radvanice and Bartovice.⁽¹¹⁾ In addition, its commissioning will enable the removal of seven free sewage outlets.⁽¹²⁾

There are currently 46 such outlets in Ostrava. The city aims to remove them in the coming years and connect the sewers to a single system through which sewage water will be routed to the wastewater treatment plants. This will significantly improve the quality of water in Ostrava's streams and, with it, the environment around the rivers Lucina, Ostravice and Oder. ⁽¹³⁾

In cooperation with NanoZone, Ostravské vodárny a kanalizace was the first company in the European Union to test the use of nanotechnology in drinking water distribution in 2018. The application of TiZonic coating containing titanium, which causes the formation of so-called active oxygen that destroys organic matter (i.e. also microorganisms or viruses), enables relatively cheap and effective improvement of drinking water quality^.⁽¹⁵⁾ On the basis of the results of the testing, which also involved the University of Mining and Metallurgy - Technical University of Ostrava and the University of Ostrava, NanoZone declared the above-mentioned hygienic technology safe, provided it was used correctly.

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