Barry Stephens speaks on Backflow Prevention in March 2013
On March 18, 2013 the ASSE South Plains Chapter welcomed Barry Stephens, Senior Water Quality Inspector for the City of Lubbock. Barry provided an excellent presentation on the basics of Backflow Prevention and highlighted the importance of backflow prevention devices in both commercial and residential applications.
Backflow is the undesired, reverse flow of non-potable or dirty water back to the clean side of the water distribution system. When this happens the potable water becomes contaminated and could eventually pollute a public water supply. This can happen at a business or at home if the business owner or home owner is not aware of the potential hazards or if adequate precautions are not taken.
There are 5 basic types of backflow prevention devices:
- Air Gap
- Atmospheric Vacuum Breakers
- Pressure Vacuum Breakers
- Double Check Valve Assembly
- Reduced Pressure Zone Backflow Preventers (RPZ)
The Texas Commission on Environmental Quality (TCEQ) regulates Backflow and siphonage under 30 TAC 290.44(h). These regulations cover the requirements, prevention, record keeping, and licensing/certification for cross-connection control. The City of Lubbock also has ordinances on responsibilities for Backflow prevention.
A common cross-connection is the ordinary garden hose. Backflow can occur if you leave a garden hose turned on and submerged in a swimming pool or in a car’s radiator to flush out the antifreeze or what Barry had described as a simple insecticide sprayer where the pesticide siphoned back into the drinking water system and when the person later got a drink of water from the hose, he consumed the toxic pesticide. He recommended and explained the use of a simple hose bib vacuum breaker for under $10 at some stores to prevent contamination into your home’s water supply.
Backflows can be prevented by using an assembly approved by the water supplier or a physical separation between the water supply and a potential source of contamination. The City of Lubbock determines the type of backflow-prevention assembly required in Lubbock based on the existing or potenial degree of the hazard.
The TCEQ also requires testing of all backflow prevention assemblies at installation by a TCEQ -licensed tester. Assemblies that are installed to protect against health hazards require annual testing.
At the conclusion of the presentation Barry conducted a demonstration of the backflow and siphonage and answered questions regarding backflow.
Barry is approved TCEQ trainer and instructor for the Texas Water Utilities Association (TWUA). He can be reached at BLStephens@mylubbock.us
On behalf of the South Plains Chapter ASSE thank you for sharing your expertise with us.