What is Backflow and What Are the Risks?

The NYC water supply system is designed to transport water from the main supply lines to each property’s plumbing system. Ideally, the water flows only in one direction, but malfunctions in the system can cause the water to flow back from your plumbing system into the water main, carrying contaminants in the process.

How Backflow Happens

Constant pressure propels water from the water main through the plumbing system at your property. If that pressure changes at any point in the overall system, it can cause backflow. The main causes of a pressure change are: 

  • A city water main break or leak in your plumbing.
  • Use of a fire hydrant in your neighborhood.
  • Problems with city water supply.

When the pressure changes and a backflow prevention device is not present, water from the property can flow back into the city water main. This water can carry human waste or chemicals, both of which could contaminate the entire water supply and result in extensive water shutoffs.

Preventing Backflow at Your Property

Because of the risks, the Department of Environmental Protection mandates that many property types have backflow prevention devices installed and tested annually. Some of the properties this requirement applies to includes:

  • Large Residential Properties
  • Commercial Kitchens
  • Supermarkets
  • Barber Shops
  • Laundromats
  • Schools
  • Car Washes, and More

If your property is involved in food processing or uses chemicals, you will likely need a backflow prevention device installed.

The most common of these devices is a reduced pressure zone (RPZ) that works by regulating the pressure in your pipes even if external pressure changes. This keeps water flowing in the right direction and prevents backflow from entering the city water supply.

After installation, the DEP requires each backflow prevention device to be tested once a year. Failure to schedule a test with a certified tester can result in fines up to $2,000 and an interruption to your water service.

For properties that need backflow prevention device installation, testing, or repair, Empire Plumbing Inc is the top local choice in NYC. Call our team today to learn more about backflow prevention or schedule a service from one of our plumbing experts.

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