The testing of the system of the express low-tech methods of biological water analysis, including biological testing methods for survival of Daphnia, ciliates, and changes in the level of chlorophyll fluorescence of algal cells, as well as the method of detection of low concentrations of oil emulsion, petroleum hydrocarbons on the behavioral response of Daphnia to assess the quality of water samples of four rivers flowing through the territory of Irkutsk have been proposed and conducted.