Backflow Prevention Practice Exam

Which scenario indicates a potential backflow problem?

1. A hose connected to a spigot resting in a pool of water

2. A faucet that drips water

3. A blocked sewer line

4. A garden hose on a reel

The correct answer is: A hose connected to a spigot resting in a pool of water

The scenario that indicates a potential backflow problem is where a hose is connected to a spigot resting in a pool of water. This situation is particularly concerning because if the water in the pool were to become contaminated, there is a direct pathway for that contaminated water to be drawn back into the potable water supply through the hose. This risk occurs due to the possibility of a negative pressure or siphon effect that can happen when there is a change in the water pressure within the system. In contrast, a dripping faucet does not create the same concern since it merely indicates a leak without any risk of contaminated water being drawn back into the system. A blocked sewer line represents a different kind of issue related to potential sewage backups, but it does not directly imply backflow into a clean water supply. Similarly, a garden hose on a reel does not present a backflow risk unless it is improperly connected to a water source or placed in a hazardous area. Therefore, the placement of the hose in a pool of water represents the clearest risk of backflow contamination.