What is the name of an indicator organism commonly monitored in water quality assessment?

Total coliforms serve as indicator organisms in water quality assessments because they are widely present in the environment, including in soil, vegetation, and the intestines of warm-blooded animals. Their presence in water typically suggests the potential for fecal contamination, which may carry harmful pathogens. Monitoring total coliforms is a standard practice for assessing the microbial quality of drinking water; if total coliforms are detected, it can indicate a need for further investigation and testing of the water supply, including checking for the presence of more harmful bacteria such as Escherichia coli.

While other organisms mentioned, such as Escherichia coli and Salmonella, are important in monitoring water quality, total coliforms provide a broader indication of water contamination. E. coli is a more specific indicator of fecal contamination, and Salmonella is a pathogen associated with waterborne diseases, but neither are as widely used as total coliforms for general assessments. Therefore, total coliforms are the preferred choice in many regulatory standards and guidelines for water quality assessment.