an unprotected actual or potential connection between a potable water system and a source of contamination (such as waste water, industrial fluids, or pesticides), where backflow can occur from the source of contamination into the potable water system
an unprotected actual or potential connection between a potable water system used to supply water for drinking purposes and any source or system containing unapproved water or a substance that is not or cannot be approved as safe, wholesome, and potable
A link or channel between pipes, wells, fixtures or tanks carrying contaminated water and those carrying potable (safe for drinking) water. Contaminated water, if at a higher pressure, enters the potable water system.
The inadvertent connection of a sewer service or private drainage system to the incorrect public sewer system. For example, a sanitary sewer service from a house that discharges to the storm sewer in the street rather than the sanitary sewer.