Backflow Device Inspection

Keep Your Water Clean. Stay In Compliance.

Backflow occurs when dirty or contaminated water flows backward into NYC's clean water supply. To prevent this risk, the city requires many buildings to install and test backflow prevention devices every year. Ensure your property is compliant and your water remains clean with our expert testing services.

Who Is Required To Have A Backflow Device?

In New York City, the installation of a backflow prevention device is mandated by the New York City Department of Environmental Protection (NYC DEP). The requirements are designed to protect the public water supply from potential contamination.

Commercial Buildings

Boilers, cooling towers, or chemical systems.

Multi-Family Residential Buildings

Buildings with water-cooled A/C or treated boilers.

Properties with Irrigation Systems

Lawn and garden sprinklers.

Properties with Fire Sprinkler Systems

Certain chemical-based systems.

Properties with Pools or Fountains

Chlorine/treatment chemicals.

Medical and Dental Buildings

Equipment tied to the water line.

Industrial Properties

Properties handling chemicals or pollutants.

Other Specific Hazards

Case by case determined by the NYC DEP.

If the NYC DEP determines that a building needs a backflow prevention device, the property owner will receive a notice and will be required to have one installed and then regularly tested. For a more detailed list, please refer to the NYC website.


JTG Master Plumbing Client Benefits

NYC’s dense plumbing system means a single faulty device can contaminate the public water supply. A missed test can mean violations and unnecessary expenses.

  • Stay Compliant: NYC law requires annual inspections for many properties
  • Protect Your Investment: Avoid costly fines and last-minute surprises
  • Peace of Mind: Owners know their property is safe and avoid costly violations.

Backflow Inspection Frequently Asked Questions

  • Why do I even need a backflow prevention device?

    Because NYC doesn’t want chemicals or dirty water from one property sneaking back into the public drinking supply. It’s required by state and city law for buildings that pose any risk to the water system. Skip it, and you’re looking at fines or even a water shutoff.

  • Which properties are on the hook for this?

    Plenty. A few common ones:

    • Buildings with irrigation systems, pools, or roof tanks
    • Properties with multiple water service lines
    • Large residential buildings with treated boilers
    • Commercial properties with cooling towers, chemical storage, or commercial kitchens
    • Healthcare facilities, schools, nursing homes
    • Industrial sites like laundries, car washes, breweries, food processing plants, tanneries, metal shops
    • Places with labs, dental equipment, or water-cooled machinery

    If your property has any risk of contaminating the water, chances are you need a device. Not sure? A Professional Engineer (PE) or Registered Architect (RA) can confirm with DEP.

  • Who’s responsible for installing this thing?

    The property owner, not the tenants. Owners must hire a Licensed Master Plumber (LMP) to install it.

  • How does installation work?

    1. A PE or RA draws up a plan and submits it to DEP for approval.
    2. Once approved, you hire an LMP to install the device.
    3. A certified tester checks that it was installed properly, and files the test with DEP within 30 days.
    4. After that, your device needs testing every year — no exceptions. DEP will mail you a reminder, but the responsibility to act (and avoid penalties) is yours.

  • How much does installation cost?

    Industry averages (parts + labor):

    • Small 1-story buildings: $3,000–$5,000
    • Small 2-story: $3,750–$5,500
    • Car washes / laundromats / small manufacturers: $5,000–$7,000
    • Office complexes / large retailers: $7,500–$13,000
    • High-rises / hospitals: $14,000–$34,000

    It isn’t cheap, but it’s a one-time installation with annual testing afterward.

  • What if my building has more than one water line?

    You’ll need a device on each service line. DEP doesn’t cut corners here.

  • I got an order to install, but the 30-day clock is almost up. What now?

    As long as DEP has written proof from your LMP, PE, or RA that installation is underway, you won’t get hit with a violation. Don’t ignore the deadline.

  • How do I schedule testing?

    For new installs: a certified tester + your LMP + the Registered Architecht or Professional Engineer who filed the plans all need to sign off and submit to DEP within 30 days.


    For annual tests: a certified tester performs the inspection, signs the form, and files with DEP. Missing an annual test = fines or water shutoff.

  • DEP says they don’t have a record of my device. What now?

    Ask your PE or RA to send DEP a record drawing plus an initial test report. Without it, the city won’t consider your device compliant.

  • Can I get an exemption?

    Yes, but it’s rare. A PE or RA has to file a formal exemption request on your behalf, on letterhead, with proof that your property meets all conditions. DEP makes the final call.

  • Where can I learn more?

    DEP’s official resources are at nyc.gov. 

    Or skip the bureaucracy, talk to us. We’ll tell you what’s required for your property, how to get it done, and how much it’ll really cost.