What is the purpose of a backflow preventer?

A backflow preventer is a crucial component in plumbing systems designed to protect the potable water supply from contamination. Its primary function is to ensure that water flows in only one direction—away from the drinking water source. This mechanism is especially important because it prevents contaminated water from flowing back into the clean water supply, which could occur due to pressure changes in the plumbing system.

For instance, if there is a sudden drop in pressure within the municipal water supply, it could create a vacuum effect that draws water from nearby sources, potentially including contaminated water. A backflow preventer acts as a safeguard, preventing this reverse flow and ensuring that safe drinking water remains uncontaminated and fit for consumption. This function is integral to maintaining public health standards and preventing waterborne diseases.

In contrast, options discussing increasing water pressure, managing temperature, or filtering out sediments relate to different plumbing functions that do not encompass the primary protective role of a backflow preventer.