Improvement of online monitoring of drinking water quality for the city of Prague and the surrounding areas.

In the article, a new method of continuous monitoring of the biological quality of raw and treated waters at the Želivka Water Treatment Plant is suggested and assessed. This water treatment plant is one of the largest water treatment plants in Europe and the largest water treatment plant in the Czech Republic with a maximum projected peak output of 7 m3.s-1 and current output of around 3 m3.s-1 of drinking water. It is the largest water treatment plant for Prague which is the capital city of the Czech Republic. Additionally, this water treatment plant also supplies drinking water to the Central Bohemia and Vysocina regions. The main intention of the research was to suggest a new system of monitoring, which can guarantee a more reliable continuous control of the safe drinking water supply for the city of Prague and the surrounding area. The suggested method represents a completely new approach to monitoring the biological quality of drinking water in the Czech Republic using the DaphTox apparatus, only two of which exist in the Czech Republic. The article describes the experience and knowledge gained during the operation of such a monitoring system, including a description of the necessary measures to ensure its proper operation with a focus on the pre-treatment of raw and chlorinated waters. Recommended simple pre-treatment methods secure optimal living conditions for monitoring organisms and have no impact on the original biological quality of monitored water which is a necessary condition for proper monitoring of biological quality.