What maintenance activity can prevent backflow issues in a water system?

Installing and maintaining backflow preventers is a crucial maintenance activity that prevents backflow issues in a water system. Backflow preventers are devices designed to keep contaminated water from flowing back into the clean water supply, ensuring that the potable water remains safe and free from harmful substances.

The importance of this device lies in its ability to block the reverse flow of water that can occur due to pressure changes within the system, often caused by events like water main breaks or sudden changes in water demand. Regular maintenance of these preventers is also essential, as they can become faulty or clogged over time, reducing their effectiveness.

The other options do not directly address the prevention of backflow. Checking water temperature, for instance, might be important for maintaining quality or efficiency but does not prevent backflow. Increasing water pressure might inadvertently exacerbate backflow issues, particularly in instances of cross-connections. Lastly, while using metal pipes can have various advantages in plumbing systems, it does not inherently prevent backflow; the design and functionality of the plumbing system, including the installation of backflow prevention devices, play a significant role in this regard.