State of the Underground Water Illustrated with the Example of Water for Częstochowa City

The following thesis’s objective is to analyze the quality of underground water for consumption, illustrated with an example of water for Czestochowa city. Although underground water is much better than surface water in terms of quality, it’s necessary to monitor the water’s quality constantly as it may decline due to many reasons during the exploitation of intakes. The importance of this is emphasized by the fact that there have been changes in water’s intake over the past 30 years in Poland. The changes involved the increase of share of underground water in the total amount of used water resources by 70.4% to 2012. Drinking water is mainly deliver to consumers by water companies, whose duties involve drawing water from natural sources and preparing it in such a way so that it is harmless to consumers. The selection of water treatment technological processes is mainly determined by raw water quality. Sanitary safety is a major priority in water treatment process, whose main aim is assuring water biostability. Biological stability of water is confirmed by the content of BDOC (biodegradable dissolved organic carbon) and AOC (assimilable organic carbon). The permissible content of AOC and BDOC in non-chlorinated water is 3÷10 and 160 μg/L, respectively. The research results show that BDOC and AOC content in raw water was 20÷95 μg/L and 5÷19 μg/L, respectively. Therefore all examined waters met requirements for biostability in terms of BDOC content. In terms of AOC content, however, only 3 out of 6 waters met these requirements. Moreover the research results show that 47% of examined quality parameters classified underground water for Czestochowa city as first class water, 29% as second class, 18% as third class and 6% as fifth class. When treating underground water as drinking water, its quality parameters met the standards of water intended for human consumption, with the exception of nitrates concentration in the water from intake A’s well, which was 62.1 mg/L and exceeded the acceptable concentration by 24%.