Which of the following factors can influence water quality in distribution systems?

All of the listed factors are crucial in determining water quality within distribution systems.

The water source significantly influences initial water quality. Different sources, such as rivers, reservoirs, or groundwater, vary in their chemical composition, temperature, and the presence of microorganisms, which all affect the final water quality delivered to consumers.

The choice of pipe material also plays a critical role. Different materials, such as iron, plastic, or copper, interact with water differently, potentially leaching materials into the water or affecting its taste and odor. For example, older iron pipes may corrode and introduce iron into the water, while plastic pipes may not have this issue.

Maintenance practices are equally important. Regular maintenance helps detect leaks, prevent contamination, and ensure that water is not stagnant in the system, which can lead to degradation in quality. Inadequate or irregular maintenance can result in biofilm growth, sediment accumulation, and other quality issues.

Therefore, recognizing that all these factors interconnect highlights their cumulative effect on overall water quality in distribution systems.