1. Chemical and Backflow Prevention Ryan Bushman – Inman Interwest Michael Moss – Division of Drinking Water Utah Nursery & Landscape Association January, 2010

15. SPRINKLING SYSTEM PRESSURE IRRIGATION WATER RP SWING JOINT CONNECTION CITY WATER

16. SPOOL CONNECTION SYSTEM

17. Dual Irrigation Connections Swing Connection Irrigation Water Source Drinking Water Source

18. Dual Irrigation Connections Reduced Pressure Principle Backflow Preventer Swing Connection

20. CODE COMPLIANT BACKFLOW PREVENTION ASSEMBLY VALVE BOX The Utah plumbing code, Section 608-16-5, REQUIRES where ‘chemicals’ are introduced into the system, the water supply shall be protected against backflow by a reduced pressure principle backflow prevention assembly. CHEMICAL FEEDER

22. VENTURI EFFECT STATIC CONDITION GAUGE PRESSURE EQUAL

23. 0 200 0 200 0 200 VENTURI EFFECT DYNAMIC CONDITION GAUGE PRESSURE DROPS VELOCITY INCREASES

24. 0 0 0 200 200 200 HIGH VELOCITY FLOW VACUUM POINTS NEGATIVE PRESSURE VENTURI CONDITION DYNAMIC CONDITION - HIGH FLOW RATE

26. 0 0 0 200 200 200

30. Reduced Pressure Principle Backflow Prevention Assembly RELEIF PORT (1) TEST PORTS (4) ISOLATION VALVES (2) MAINTAIN AS AN ASSEMBLY

31. GOOD INSTALLATION

32. PROBLEM INSTALLATIONS Installed Below Grade Installed In Ceiling and is NOT Accessible

37. PROBLEM INSTALLATION

38. PROBLEM INSTALLATIONS

42. PROBLEM INSTALLATION

49. QUESTIONS?