Florida Wastewater Practice Test

Which indicator is commonly used to assess the microbiological quality of water?

1. pH level

2. Coliform bacteria

3. Specific conductance

4. Dissolved oxygen

The correct answer is: Coliform bacteria

Coliform bacteria are widely recognized as an indicator of microbiological quality in water because their presence suggests potential contamination by fecal material, which can contain harmful pathogens. These bacteria are relatively easy to detect and enumerate, making them an effective tool for assessing water safety for human consumption and recreational use. When testing for water quality, the detection of coliform bacteria, particularly fecal coliforms, serves as a proxy for the presence of more harmful microorganisms that may be lurking in the water, such as viruses and protozoa. Because coliforms thrive in the intestines of warm-blooded animals, their presence can have significant implications for public health. This is why water quality monitoring programs often focus on these microorganisms to ensure compliance with health regulations and to safeguard public health. In contrast, pH level, specific conductance, and dissolved oxygen, while important parameters for assessing other aspects of water quality, do not directly indicate the presence of pathogenic microorganisms. pH influences chemical reactions in water, specific conductance measures the ionic content, and dissolved oxygen is crucial for aquatic life. Each of these factors contributes to the overall health of water ecosystems, but they do not serve as reliable indicators for microbiological contamination.