Microbiological Water Quality of the Danube River: Status Quo and Future Perspectives

Abstract

Fecal microbial pollution is a major problem throughout the Danube River Basin, posing a threat to various types of water use, including drinking water production from river bank filtrates, water supply for agricultural and industrial use, and the role of the river as a recreational space. Fecal microbial pollution is introduced into the river by point sources, such as discharges of treated or untreated sewage from human sources or livestock, and by nonpoint sources, such as urban and agricultural runoff. In addition, fecal input from wildlife may be of importance in specific regions. Despite huge efforts to improve wastewater management in the past decade, in many sections, the river and its tributaries exhibit very high levels of fecal microbial pollution. To assess microbiological water quality, indicators of fecal pollution are used as surrogates for the potential presence of intestinal pathogens. However, the standard indicators cannot provide any reliable information regarding the origin of fecal pollution, nor can their concentration levels be directly related to human health risks for many types of exposure and situations.