What aspect of water quality is CFU primarily associated with?

CFU, or Colony Forming Units, is a measure used to estimate the number of viable microorganisms in a sample, thus directly correlating with microbial count. This metric is particularly important in water quality testing because it helps determine the level of bacteria, pathogens, and other microbes present in water, which can have significant implications for health and safety. High CFU values can indicate contamination, necessitating further investigation or treatment to ensure the water is safe for consumption or use. As such, when evaluating water quality, CFU serves as a critical indicator of the biological aspect of that quality, focusing specifically on the presence and quantity of microorganisms.