Source

      Water for drinking and industrial purposes in Cieszyn is taken from the intake in Pogórze (Skoczów Muncipality). The intake was built in 1936 and is located in a fork of the Wisła and the Brennica. 24 dug and drilled wells 6-13 m deep are currently in use. The wells supply underground water that infiltrates from the Wisła and the Brennica. Maximum efficiency of the intake in Pogórze amounts to 750 m³ water per hour which is 18,000 m³ per day. Also other municipalities located along the Pógorze-Cieszyn water main use the intake. The administrator of the intake is Wodociągi Ziemi Cieszyńskiej Sp. z o.o (Cieszyn Water Supply System Ltd).

Usage

      In the Cieszyn area there is a water-pipe network over 211 km long to which about 96% of households are connected. The water usage between 1992 and 2002 in Cieszyn is shown in table 12. There is a declining tendency of water usage for household and industrial purposes.

Table 12.
Water consumption in Cieszyn in (data: Wodociągi Ziemi Cieszyńskiej Sp. Z o.o.–Cieszyn Regional Water).

      During temporary water deficiencies in Cieszyn, water, amounting to 1,000 m³/d, is delivered from the Czech Republic and also the same amount is delivered from the intake on the Wisła Czarne reservoir. It is also possible to cover the water deficit from intakes within the Hażlach Municipality.

Quality

      Water obtained from the wells in Pogórze is naturally filtrated through gravel deposits in the ground. Before it is 'allowed' into the network, the water is disinfected with two mechanical chlorators and treated with sodium hypochloride which is supposed to destroy any bacteria the water obtained from the well may contain.
      Water quality is constantly monitored by the Powiatowa Stacja Sanitarno-Epidemiologiczna (County Medical Epidemiological Station) in Cieszyn. In terms of physical, chemical and bacteriological qualities water is tested on the intake site and then before allowing it into the system and at 'network ends' (in the town). The quality of water provided to Cieszyn is good and only occasionally has it been found that standards of some parameters have been exceeded which, however, does not have crucial influence on taste and health factors.
      What has to be discussed separately is the presence of carbon dioxide (CO2) in drinking water in Cieszyn and its possible effect on the health of the residents. CO2 exists in almost all natural waters; it originates from the atmosphere, geochemical processes or the decomposition of plants and animals. While the presence of CO2 in surface waters is evidence of its pollution, its presence in underground waters does not really matter from a sanitary point of view. CO2 in drinking water is not directly hazardous to people and its presence may enhance the water's taste and refreshing qualities. However, in some circumstances CO2 may have direct influence on human health and serious ill effects on the economy. The so-called 'corrosive' or 'aggressive' form of CO2 dissolves metal, concrete and other materials. If such a phenomenon takes place in the pipes of a water-supply system, large amounts of metals that are hazardous to human health get into drinking water. Water obtained from the intake in Pogórze has been confirmed to contain 'aggressive' CO2 in quantities typical of water from submontane areas. The acceptable standard of CO2 concentration in drinking water has not been set: it is very difficult to determine if CO2 quantities in drinking water are harmful and, if so, to what extent. There are plans to install a filtrating system in the Pogórze intake in 2003 which will contribute to the reduction of CO2.