Abstract
The article presents data on discharges of pollutants into surface water bodies of Almaty region. It has been shown that large volumes of discharges of insufficiently treated wastewater degrade the ecological state of river ecosystems and reduce the quality of natural water. The purpose of the study was to assess the water quality of the Big Almaty River in the influence zone of Almaty by microbiological indicators. The results of physicochemical as well as microbiological analyses of the Big Almaty River water are presented. As a result of the studies, the dependence of the number of common saprophytic bacteria, common coliform bacteria and coliphages on the chemical composition of water, hydrological and weather conditions was revealed. A comparative analysis of water quality in the upper and lower reaches of the Big Almaty River was carried out. A positive correlation was found between the number of saprophytic bacteria and water levels, between saprophytic bacteria and water flow rates, saprophytic bacteria and precipitation levels. A reproducible increase in the number of coliphages in the subglacial period has been established. A negative correlation was found between the number of coliphages and mineralization, the number of coliphages and water temperature. The results obtained can form the basis of the information base for making decisions on the implementation of environmental protection measures aimed at reducing the level of pollution of water bodies.