Backflow Prevention

Backflow Prevention

Baby filling wading pool with water

You can count on Greenville Utilities to provide you with safe, fresh, clean water. We are dedicated to that goal and committed to your safety. That’s why we want to make sure you know how to prevent backflow.

What is Backflow?
Most of the time water flows “forward” from the water distribution system into your residence. Backflow is the term used to describe the “backward flow” of water. In other words, backflow would occur when water from your home “flows back” into the water supply. Backflow can also be caused when water from a garden hose “flows back” into your home. If water flowing backwards contains hazardous chemicals or bacteria, it can cause an unhealthy or dangerous situation.

How Does It Occur?
Backflow can occur because of something as simple as an ordinary garden hose. As an example, you are washing your car and the phone rings. You leave your garden hose in a bucket of soapy water. While you are on the phone, a water main breaks down the street and the water pressure quickly and momentarily has a significant drop, creating a vacuum. Like sucking on a straw, the vacuum could pull the soapy water into your home’s water system. At the same time, your spouse gets a glass of water from the kitchen faucet. What should be a refreshing drink actually ends up being contaminated by the effects of backflow.

Significant water pressure drops are uncommon, but they can happen. Here are some precautions you can take to safeguard your family.

What Can You Do to Prevent Backflow?

  • Never submerge hoses in buckets, pools, spas, tubs or sinks.
  • Always keep the end of the hose away from possible contaminants.
  • Do not use any spray attachments (pesticide applicators, portable pressure washers, drain openers or radiator flush kits) without a backflow prevention device. These devices are available for less that $10 at most home improvement stores. Ask for a hose bibb vacuum breaker.


Ready for Winter?
Click here for a video about how to winterize your backflow preventer.

Cross Connection Control
Commercial and Industrial customers are responsible for installing and testing backflow prevention assemblies on their water service connections. The assemblies are tested when they are installed and then annually thereafter by a Greenville Utilities-certified tester. In addition, residential customers with new irrigation systems must be connected to a separate irrigation water meter.

GUC holds semi-annual tester's certification courses, in the spring and fall, to enable plumbers and technicians to better service the needs of our customers. The tester’s certification courses are part of our comprehensive program designed to protect our water system from harmful cross-connections. All backflow testers must complete a re-certification course every two years.

Cross Connection Control and Backflow Prevention Assembly Tester Course
The next Backflow tester course is scheduled for October 12, 13, 18, 19, and 20 Click here for registration information. 

Re-certification Course
The re-certification course will be offered November 15 - 17 or December 13 - 15. Click here for details.

Current List of Certified Testers 

Backflow Test and Maintenance Form

For more information about preventing backflow and GUC's Cross-Connection Control Program, call 252-551-3399.


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