Which testing method is used to determine the presence of bacteria in water samples?

Coliform testing is the recognized method for determining the presence of bacteria in water samples. Coliform bacteria, specifically fecal coliforms, are indicators of contamination and the potential presence of harmful pathogens. This testing is essential in water quality assessments, especially in drinking water sources.

Coliforms are typically used as a standard because their presence suggests that other pathogenic microorganisms may also be present, leading to health risks. The testing involves culturing water samples to identify and quantify the coliform bacteria, offering a clear indication of microbial safety.

Other testing methods, such as pH testing, help assess the acidity or alkalinity of water but do not provide information on microbial presence. Nitrate testing measures the concentration of nitrates, which can indicate contamination from fertilizers or septic systems but does not specifically assess bacterial contamination. Chlorine testing is used to measure disinfectant levels in water but does not indicate the presence of bacteria. All these methods serve different purposes in water quality evaluation, making coliform testing the specific choice for identifying bacterial contamination.