Backflow Prevention
to Protect the Drinking Water System

What is a backflow prevention device and why is it important?

A backflow prevention device is a special kind of equipment designed to ensure that water from a private plumbing system cannot be drawn back into the public water supply (the OWASA water system). Backflow prevention is also referred to sometimes as “cross-connection control.”

A backflow can occur under circumstances such as a break or rupture in a large water main, or intense water use for fire suppression. When large amounts of water flow out of a broken pipe or a fire hydrant, a suction or negative pressure condition can result in water being drawn back to the water release point from nearby pipes including our public mains and private water service pipes/ plumbing systems.

Water in private plumbing systems, plumbing fixtures and other devices connected to the plumbing system may be contaminated in some conditions after the water leaves the OWASA system.

Therefore, in accord with North Carolina’s health standards for public drinking water systems, the OWASA Board of Directors has adopted an ordinance requiring that certain water customers have a backflow prevention device installed on the private service pipe on the customer’s side of the OWASA water meter.

This ordinance requires installation and annual inspection of an appropriate type of backflow prevention device for many non-residential buildings/water uses, at residential locations with automated sprinkler systems, etc.

If you have any questions or comments, please contact:

Thurman Green, Manager, Distribution and Collection Systems Manager
PO Box 366, Carrboro, NC 27510
Telephone: 919-537-4224; E-mail: tgreen@owasa.org
OWASA fax number: 919-968-4464