Hygiena 2019, 64(1):27-30 | DOI: 10.21101/hygiena.a1707

Accident in the drinking water supply of Nová Ves and its investigation

Kamila Podráská¹, Libuše Polanská¹, František Kožíšek², Petr Pumann², Daniel Krsek²

¹ Krajská hygienická stanice Středočeského kraje se sídlem v Praze, Praha, Česká republika

² Státní zdravotní ústav, Praha, Česká republika

The paper describes a water quality incident in a small public water supply in Central Bohemia in the summer of 2017. People living in one part of the village consisting of about 40 recently built family houses experienced a short supply break (due to a blackout) and afterwards they received green-coloured tap water (due to algae) and later repeatedly microbiologically contaminated water (E. coli and coliforms). It might have resulted in about 20 illnesses, but medically confirmed was only one case of a child hospitalized. Water was banned to drink by the Public Health Authority for about a month. The water supply operator could not - in spite of repeated measures (flushing, disinfection) - restore safe water quality, nor to reveal the cause of contamination. An illegal connection between a private well and the public supply was suspected. Within one month they noticed that water contamination is worse after dry and hot days and started a systematic examination of garden irrigation practices in the affected area. Finally it was found that the owner of one house took irrigation water also from the adjacent brook and that his piping was interconnected not only with his private well, but also with the public supply and that the pump used had pressure enough to introduce surface water in to the public water mains.

Keywords: drinking water contamination, accident, water supply

Received: November 2018; Accepted: December 5, 2018; Published: February 28, 2019  Show citation