1. Indicator Organisms in Wastewater Treatment Wetlands Jepson Sutton SWES 574 10-31-02

2. Indicator Organisms The detection of pathogenic organisms is a time-consuming, labor-intensive task, requiring highly trained technicians For this reason, scientist have identified certain organisms that, when detected, are a definitive indication of fecal contamination.

3. Indicator Organisms Indicator organisms are considered normal flora (always present) in the digestive system of all warm-blooded animals, including humans. The detection of indicator organisms suggests that enteric pathogenic microorganisms may also be present due to the fecal contamination.

4. Characteristics of an effective Indicator It is normal flora of warm-blooded animals It is present when pathogens are present, and undetected in uncontaminated samples The indicator should be found in greater concentrations than pathogens. It should have a similar resistance to environmental stress and water treatment processes as the pathogen.

5. Characteristics of an effective Indicator It must require a host for replication. (eliminates replication in the environment) Rapid, easy, and inexpensive detection methods Nonpathogenic

6. Types of indicator organisms Total coliforms –First group of indicators developed –Problematic because of the ability of some species to replicate in the environment Fecal coliforms –Subgroup of Total coliforms –Restricted to fecal origins Fecal Streptococci –Primarily an indication of animal fecal pollution –FC/FS ratio

7. Types of indicator organisms Anaerobic bacteria –Clostridium: spore forming bacteria / environmental resistance –Bacteroides: limited environmental resistance Bacteriophage –Viruses that require certain bacterial hosts for replication –Indication of both bacterial and viral contamination.