Waterworks Best Practices: Containment Backflow Preventer Design & Placement
1 like1,044 views
The document discusses best practices for the placement and design of containment backflow preventers (BFPs), advocating for outdoor installations to avoid indoor flood hazards and increase property value. It emphasizes the importance of adhering to plumbing codes, reducing liabilities for owners and designers, and suggests that outdoor installations can serve as an effective 'insurance policy' against water contamination and flooding. Additionally, it highlights the growing acceptance and implementation of these best practices across various U.S. cities.
Waterworks Best Practices: Containment Backflow Preventer Design & Placement
- 1. …poorly understood by designers Best Practices: Containment Backflow Preventer Placement Best Practices: Containment Backflow Preventer Design & Placement
- 2. Best Practices: Containment Backflow Preventer Placement “…. The return of any water to the public water system after the water has been used for any purpose on the customer’s premises or within the customer’s piping system is unacceptable and opposed by AWWA. …”
- 3. Bottom Line for the future: Best Practices: Containment Backflow Preventer Placement More Containment More RPZs More Outdoor Aboveground Installations
- 4. Why place a BFP outside? Best Practices: Containment Backflow Preventer Placement 1. RPZs are an indoor flood hazard
- 5. “Before an RPZ is located, consideration should be given to both how much water will be discharged, and where it will drain. Consideration must be given to the drain system to assure the drainage system can handle the load. If a drain is not capable of accepting the flow, other choices as to the location of the valve, such as outside in a heated enclosure, should be made.” -2006 ASPE Plumbing Engineering Design Handbook, vol 2, p 70 Best Practices: Containment Backflow Preventer Placement Why outside?
- 6. Why outside? Inside a building can be a major liability. Best Practices: Containment Backflow Preventer Placement
- 7. Where to place a BFP? Best Practices: Containment Backflow Preventer Placement
- 8. Best Practices: Containment Backflow Preventer Placement Backflow Failure
- 9. 2. Revenue & prop value: Indoor RPZs Reduce the rentable square footage of a building reducing revenue & property value Why outside? Best Practices: Containment Backflow Preventer Placement
- 10. Charlotte, NC: 32 SF Columbus, OH: 36 SF Suffolk Cty, NY: 33.3 SF Arlington, TX: 32 SF How much space is lost? Average: 33.325 SF Annual Rent Value: $999.75 (based on Class A Office @ $30 psf) 25-year Cash Flows: $34,149.22 (based on 2.5% inflation) Net Present Value: $12,156.48 (based on 9% discount rate) Best Practices: Containment Backflow Preventer Placement
- 11. Net Present Value - $12,156.48 “If you pay me this today, I am indifferent to the loss of those income streams over the next 25 years” QUESTION: Will placing the system inside save $12,156.48 over any other method? … it depends on how much it costs to put it outside. What’s that space worth? Best Practices: Containment Backflow Preventer Placement
- 12. Aboveground heated enclosure for 3” BPA with heat. $1,000 $1,120 $1,800 $3,920 $3,266 $1,200 $1,800 $6,266 Best Practices: Containment Backflow Preventer Placement Option A: Use conventional model Watts 957 NRS Option B: Use new ”n-type” model Watts 957N NRS
- 13. Indoor Containment BPA +$12,156.48 +$8,236.48 +$5,890.48 No Containment BPA +$0.00 Owner’s Cash Benefit: Best Practices: Containment Backflow Preventer Placement
- 14. 3. Fire safety: Indoor water resources for fires unnecessarily add risk to firefighters Why outside? Best Practices: Containment Backflow Preventer Placement
- 15. 1. RPZs are not allowed to be installed in Vaults Why not a vault? Best Practices: Containment Backflow Preventer Placement
- 16. 2. ConfinedSpaceHazards: Vaults are dangerous and expensive to maintain and repair. New OSHA Guidelines, May 4, 2015: Google: Pre/Post-Entry Information Exchange Duties of Host Employers and Controlling Contractors Why not a vault? Best Practices: Containment Backflow Preventer Placement
- 17. Best Practices: Containment Backflow Preventer Placement Why not a vault? 3. Flooded vaults violate the International Plumbing Code. 608.1 General. A potable water supply system shall be designed, installed, and maintained in such a manner so as to prevent contamination from nonpotable liquids, solids or gases being introduced into the potable water system through cross connections or any piping connections to the system. - International Plumbing Code 2013
- 18. 4. Aboveground fire BPA enclosures with FDCs are safest, most efficient solution for firefighters Why not a vault? Best Practices: Containment Backflow Preventer Placement
- 19. 5. Retrofits: Water use hazard changes over time – whether by changing tenant or changing guidelines – force enclosure retrofits and leave vaults empty Why not a vault? Best Practices: Containment Backflow Preventer Placement
- 20. - Plumbing Standards Magazine, Fall 2009 “An outdoor, aboveground BFP installation may be the best way to 1) reduce the owner’s exposure to damage caused by flooding....and the corresponding water contamination caused by a cross-connection; and 2) reduce the legal liability of the design engineers, the installers, and the certified testers whose professional actions, in part, may have otherwise caused the flooding harm. The water industry has a nationally accepted design criteria in ASSE’s Standard-1060 to protect these installations. It’s a win-win-win ‘insurance policy’.”Douglas Cregor, Esq. Best Practices: Containment Backflow Preventer Placement Why an Enclosure? 6. Insurance Policy
- 21. 90.% Best Practices: Containment Backflow Preventer Placement Texas Survey Results What do design engineers think?
- 22. Best Practices: Containment Backflow Preventer Placement Texas Survey Results
- 23. 72.7% Best Practices: Containment Backflow Preventer Placement Texas Survey Results
- 24. 78.2% Best Practices: Containment Backflow Preventer Placement Texas Survey Results
- 25. Seattle Raleigh Charlotte Austin Nashville Albuquerque Long Island Denver Las Vegas LynchburgColumbus Chicago Forth WorthRoswell Best Practices: Containment Backflow Preventer Placement Portland ArlingtonGwinnett City Chesapeake What’s happening around the country that helps us understand where all this is going?
- 26. Chicago, IL Best Practices: Containment Backflow Preventer Placement
- 27. Chicago, IL Best Practices: Containment Backflow Preventer Placement
- 28. Chicago, IL Best Practices: Containment Backflow Preventer Placement
- 29. Central Ohio Best Practices: Containment Backflow Preventer Placement
- 30. Fort Worth, TX Best Practices: Containment Backflow Preventer Placement
- 31. Fort Worth, TX Alpine Bedford Boerne Carrollton Cleburne College Station Denison Farmington Farris Franklin Grand Prairie Haltom Texarkana Waco Waskom White Settlement Addison Arlington Buda Cedar Hill Colleyville Crowley Denton Duncanville Fort Worth Franklin Gainesville Highland Village Midlothian Roanoke Round Rock Saginaw Same language added to muni code in past 5 years Best Practices: Containment Backflow Preventer Placement
- 32. Central Virginia Best Practices: Containment Backflow Preventer Placement
- 33. Roswell did Best Practices: Containment Backflow Preventer Placement What Can Cities/Counties Do? 1. Adopt standard details consistent with best practices
- 34. Denver did Best Practices: Containment Backflow Preventer Placement What Can Cities/Counties Do? 1. Adopt standard details consistent with best practices
- 35. Columbus did Best Practices: Containment Backflow Preventer Placement What Can Cities/Counties Do? 1. Adopt standard details consistent with best practices
- 36. Charlotte did Best Practices: Containment Backflow Preventer Placement What Can Cities/Counties Do? 1. Adopt standard details consistent with best practices
- 37. Las Vegas did too Best Practices: Containment Backflow Preventer Placement
- 38. Best Practices: Containment Backflow Preventer Placement Tell DFW to Follow their Lead The city of Arlington did in February 2016
- 39. 2710 Landers Avenue ∙ Nashville, TN 37211 ∙ (800) 245-6333