Turbidity is a key indicator of water quality because it signals the presence of what?

• A. Suspended particles that can harbor pathogens
• B. Dissolved minerals
• C. pH level
• D. Water temperature

Answer: (C)

Turbidity measures how cloudy water is due to suspended particles. Those particles—like soil, silt, organic matter, and microbes—can provide surfaces for microbes to attach to, including potential pathogens. Because disinfection can be less effective when particles shield microbes, turbidity becomes a useful indicator of microbial presence and overall water quality risk. Dissolved minerals, pH, and temperature influence other properties of water but do not cause cloudiness, which is the hallmark of turbidity. So turbidity signals the presence of suspended particles that can harbor pathogens.