What is the primary reason for installing backflow preventers in buildings in flood-prone areas?

• A. To prevent wastewater from backing up into interior spaces during pressure changes.
• B. To prevent clean water from entering pipes.
• C. To improve water pressure in the plumbing system.
• D. To filter out contaminants from incoming water.

Answer: (A)

Backflow prevention protects the potable water system from contamination when pressure in the distribution system changes, such as during floods. In flood-prone areas, sewer lines can become surcharged or experience reverse flow, which can push wastewater back into a building’s piping. The backflow preventer creates a barrier that stops that contaminated water from entering interior pipes and fixtures, keeping the drinking water supply safe. This device isn’t about keeping clean water from entering pipes, increasing water pressure, or filtering contaminants; its sole purpose is to prevent backflow of wastewater into the building during pressure changes.