1. Backflow Prevention

2. Cross Connection Control
Charleston
Mt. Pleasant
Summerville

3. Polluted versus Contamination
Pollutant risk – color or odor
Contaminant risk – health hazard

4. Polluted versus Contamination
Irrigation considered contamination risk
Pesticides and fertilizers

5. Cross Connection
Cross connection is any connection between potable and non-potable water

6. Backsiphonage
Backsiphonage is the reverse flow of water

7. Backsiphonage

8. Cross Connection

9. Back pressure
Back pressure is continuous pressure back toward potable water
Elevation example

10. BACKFLOW PREVENTERS (Can be TESTED)
Reduced pressure (RP)
Most pressure loss
$180
Backpressure, pressure relief valve
Avoid water submersion of relief valve
12 psi loss

11. Reduced pressure (RP)

12. BACKFLOW PREVENTERS (Can be TESTED)
Reduced pressure (RP)
12” above ground installation

13. Reduced pressure (RP)

14. BACKFLOW PREVENTERS (Can be TESTED)
Pressure Vacuum Breaker (PVB)
Spring-loaded check valves and air-inlet prevent backsiphonage only
Not intended for backpressure
$70 cost
5 psi loss

15. Pressure Vacuum Breaker (PVB)

16. BACKFLOW PREVENTERS (Can be TESTED)
Pressure Vacuum Breaker (PVB)
12” above highest head installation

18. BACKFLOW PREVENTERS (Can be TESTED)
Double Check Valve
Spring loaded check valves only
No relief valve
5 psi loss

19. Double Check Valve

20. BACKFLOW PREVENTERS (CANNOT be TESTED)
Dual check valve
Spring loaded check valves only

21. BACKFLOW PREVENTERS (CANNOT be TESTED)
Atmospheric Vacuum Breaker (AVB)
Float inlet
Not intended for continuous pressure
One for every valve, 6” above highest head
Cheapest
2 psi loss

22. Atmospheric Vacuum Breaker (AVB)

23. BACKFLOW PREVENTERS (CanNOT be TESTED)
Anti-Siphon Valve
Control valve with built-in AVB

24. OTHER BACKFLOW PREVENTION
AIR GAP
Breaks vacuum of backsiphonage

25. OTHER BACKFLOW PREVENTION
HOSE BIB
Vacuum breaker attachment

26. INSTALLATION Install after POC
A licensed plumber must tap into potable water system
Exception is homeowner that can tap into own water supply

27. INSTALLATION COPPER PIPE
Two feet of copper (type K) in ground, before and after backflow preventer
Rigidity
Exposure

28. DHEC
South Carolina Department of Health and Environmental Control (DHEC)

32. Copper Pipe
Sweating copper pipe

33. Copper Pipe
Sandpaper or emery cloth to clean pipe

34. Copper Pipe
Flux surfaces
Helps draw in solder

35. Copper Pipe
Dry-fit pipe and fitting

36. Copper Pipe
Heat pipe connection

37. Copper Pipe
Touch joint with solder
Melts and draws inside

38. Copper Pipe

44. TESTING Tested annually by licensed tester Certified BF inspector
DHEC, John Watkins
3 day class ($225)
Equipment ($700)