Tempe Arizona Water Distribution Grade 3 & 4 Practice Exam 2026 - Free Water Distribution Practice Questions and Study Guide

Chlorine is a powerful disinfectant widely used in water treatment processes primarily because of its ability to kill or inactivate harmful microorganisms, including bacteria, viruses, and protozoans. When chlorine is added to water, it reacts with these microorganisms, effectively disrupting their cellular processes and leading to their death or inactivation. This makes chlorine an essential component in ensuring that water is safe for human consumption and public health.

The use of chlorine for disinfection is critical in reducing the risk of waterborne diseases that can arise from contaminated water. Therefore, its primary role is to eliminate potential pathogens rather than enhance taste, increase pH or remove heavy metals, which are functions associated with other treatment processes or chemicals.