This review discusses the main bacterial diseases transmitted through water, including cholera, typhoid fever, and bacillary dysentery. It focuses on the biology, ecology, and life cycles of the causative agents, as well as the importance of pathogenic Escherichia coli and emerging pathogens in waterborne diseases. The review emphasizes the role of fecal indicator bacteria in microbiological water analysis, highlighting their advantages and limitations as markers. It also discusses the main sources of bacterial fecal pollution in environmental waters and the indicators that should be used in current drinking water microbiological analysis. The review concludes that safe drinking water for all is a major challenge of the 21st century, and that microbiological control of drinking water should be the norm everywhere. Routine basic microbiological analysis of drinking water should include the detection of Escherichia coli by culture methods. Whenever possible, fecal coliform determinations should be complemented with the quantification of enterococci. More studies are needed to assess the reliability of ammonia for preliminary screening of fecal pollution outbreaks. Financial resources should be allocated to better understand the ecology and behavior of human and animal fecal bacteria in environmental waters. The review also discusses the ecology and cycle of various bacterial pathogens, including Vibrio cholerae, Salmonella, Shigella, and pathogenic Escherichia coli. It highlights the importance of understanding the transmission routes and risk factors for these pathogens, as well as the need for improved water quality monitoring and control. The review concludes that the use of fecal indicator bacteria is essential for assessing the risk of waterborne diseases and that further research is needed to develop more effective indicators for detecting these pathogens in water.This review discusses the main bacterial diseases transmitted through water, including cholera, typhoid fever, and bacillary dysentery. It focuses on the biology, ecology, and life cycles of the causative agents, as well as the importance of pathogenic Escherichia coli and emerging pathogens in waterborne diseases. The review emphasizes the role of fecal indicator bacteria in microbiological water analysis, highlighting their advantages and limitations as markers. It also discusses the main sources of bacterial fecal pollution in environmental waters and the indicators that should be used in current drinking water microbiological analysis. The review concludes that safe drinking water for all is a major challenge of the 21st century, and that microbiological control of drinking water should be the norm everywhere. Routine basic microbiological analysis of drinking water should include the detection of Escherichia coli by culture methods. Whenever possible, fecal coliform determinations should be complemented with the quantification of enterococci. More studies are needed to assess the reliability of ammonia for preliminary screening of fecal pollution outbreaks. Financial resources should be allocated to better understand the ecology and behavior of human and animal fecal bacteria in environmental waters. The review also discusses the ecology and cycle of various bacterial pathogens, including Vibrio cholerae, Salmonella, Shigella, and pathogenic Escherichia coli. It highlights the importance of understanding the transmission routes and risk factors for these pathogens, as well as the need for improved water quality monitoring and control. The review concludes that the use of fecal indicator bacteria is essential for assessing the risk of waterborne diseases and that further research is needed to develop more effective indicators for detecting these pathogens in water.