To protect New York City’s drinking water supply systems from contamination, DEP has a robust water quality monitoring program and regularly performs sampling throughout the City to ensure all relevant State and federal standards are met.
DEP also works to prevent contamination before it occurs by ensuring that City businesses comply with all relevant City and State codes. A key component of this enforcement and inspection initiative is DEP’s Cross Connection Control Program, which requires certain businesses to install and operate approved backflow prevention devices and enforces Part 5 Section 5-1.31 of the State Sanitary Code and Title 15, Chapter 20 of the Rules of the City of New York.
Backflow devices prevent contaminated water or chemicals from flowing back into the drinking water supply if there is a sudden or unexpected change in water pressure. If a property requires a backflow prevention device, they must be installed on all water service lines to the property. Appropriate backflow prevention devices can be identified by a Professional Engineer (PE), Registered Architect (RA) or Licensed Master Plumber (LMP).
