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January, 2017
American Backflow Prevention
Association Presentation:
Backflow Installation and Design
Presented by
Randy H...
New professional liability risk for engineers
Best Practices: Containment Backflow Preventer Placement
The entire water sy...
Best Practices: Containment Backflow Preventer Placement
It seems very clear that we will not get
rid of the problem of pl...
Best Practices: Containment Backflow Preventer Placement
And with this new risk realization comes a new Interested Party. ...
Water utilities are seeking more containment
backflow protection than ever before.
Consider:
“…. The return of any water t...
More containment systems are being specified as
RPZ, regardless of hazard threshold, than ever
before.
Consider:
Best Prac...
Best Practices: Containment Backflow Preventer Placement
Consider:
For containment, AWWA, ASPE, & the legal
community reco...
1. Why outside?
2. Why not a vault?
3. Momentum: What is driving the change to
better solutions?
Today We’ll Cover:
Best P...
1. RPZs are an
indoor flood
hazard
“Before an RPZ is located, consideration should be
given to both how much water will be...
Best Practices: Containment Backflow Preventer Placement
Why Outside? Indoor Flood Risk.
Flow Stop
The most important thin...
Loss of pressure
#2 valve
blocked
Consider a flow-stop situation, one that
might naturally occur at the end of the day.
If...
#1 valve
Failure
Normal
delivery
pressure
Now consider a failure of the #1 check
valve. Under normal operating conditions,...
#1 valve
Failure
Blockage
relief
valve
Demand
Normal
delivery
pressure
This creates the conditions for the “perfect
storm”...
No
demand
Normal
delivery
pressure
The real damage begins when the user
stops using water such as at the end of a
work day...
Best Practices: Containment Backflow Preventer Placement
Why Outside? Indoor Flood Risk.
This flood occurred in a hospital...
Best Practices: Containment Backflow Preventer Placement
Why Outside? Indoor Flood Risk.
The insurer sought recovery from ...
So if an RPZ is designed to dump water,
then drain capacity is the issue. The
chart on the right is from the
manufacturer ...
This is an article published June
2013 in the Chicago chapter of the
American Society of Plumbing
Engineers written by Dav...
Backflow Failure
Why Outside? Indoor Flood Risk.
Watch this video
showing a check
valve failure and
the resulting flood
wa...
Charlotte: 32.000 SF
Columbus: 36.000 SF
Suffolk Cty: 33.333 SF
Arlington: 32.000 SF
Average: 33.325 SF
Why Outside? Incre...
NPV:
Landlord has lost this amount of value by
placing CBPA inside.
CONSIDER:
1. If space is recaptured for rental value, ...
Aboveground heated enclosure
for 3” BPA with heat.
Option A:
Use conventional model
e.i., Watts 957 NRS
Safe-T-Cover 300-A...
$1,000
$1,120
$1,800
$3,920
plus assembly
$3,266
$1,200
$1,800
$6,266
plus assembly
Irrational Costs, Irrational Risks!
Wh...
“How much more value does my building have with the additional rent?”
ANSWER:
Irrational Costs, Irrational Risks!
Year Ann...
1. Why outside?
2. Why not a vault?
3. Momentum: What is driving the change to
better solutions?
Today We’ll Cover:
Best P...
Why not a vault? No RPZs in Vaults
Best Practices: Containment Backflow Preventer Placement
41 states have written code
th...
We’ve all seen the extraordinary measures
OSHA imposes to legally access vaults for
maintenance tasks. fresh air exchange
...
Why not a vault? Liability
Best Practices: Containment Backflow Preventer Placement
When a vault floods like this one, the...
Why not a vault? Liability
Best Practices: Containment Backflow Preventer Placement
The foundation added stronger language...
Why not a vault? Changing Demands
Best Practices: Containment Backflow Preventer Placement
Buildings, through their normal...
Why not a vault? Changing Demands
Best Practices: Containment Backflow Preventer Placement
A few years later, the city cha...
Why not a vault? Legal Community Support
Best Practices: Containment Backflow Preventer Placement
Before his recent death,...
1. Why outside?
2. Why not a vault?
3. Momentum: What is driving the change to
better solutions?
Today We’ll Cover:
Best P...
Best Practices: Containment Backflow Preventer Placement
This past fall at the Bi-Annual ASPE
National conference, one of ...
Best Practices: Containment Backflow Preventer Placement
Seattle, WA
Raleigh, NC
Charlotte, VA
Austin, TX
Nashville, TN
Al...
Where is the momentum? Smaller solutions.
12’
6’8” 5’2”
5’4”
Best Practices: Containment Backflow Preventer Placement
Cons...
Best Practices: Containment Backflow Preventer Placement
Where is the momentum? Adjustments for aesthetics.
AWWA has long ...
3. CivilengineersarereadytotakeonthetaskifSDsexist
Take-Aways
1. 3”andlargerCBPAsshouldnotbeinstalledindoorsandMEPsare
see...
Thank You!
American Backflow Prevention
Association Presentation:
Backflow Installation and Design
Best Practices: Contain...
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Containment Backflow Installation and Design

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On January 12, 2017 consultant for Safe-T-Cover Randy Holland presented this to the San Antonio branch of the American Backflow Prevention Association at the TCEQ headquarters. Now you can learn all about the new professional liability concerns and solutions they covered as well. Now that industry thought leaders have started making recommendations on RPZ backflow preventer installation, it has caught the legal industry's attention.

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Containment Backflow Installation and Design

  1. 1. January, 2017 American Backflow Prevention Association Presentation: Backflow Installation and Design Presented by Randy Holland Environmental Quality Consultant
  2. 2. New professional liability risk for engineers Best Practices: Containment Backflow Preventer Placement The entire water system design community is struggling with new professional liability risk involving the location of containment backflow preventer systems. This is not because of a new design practice, but because of new information about the old practices. In the past 2 years important organizations and noted industry leaders have added new warnings with much stronger language that not only change recognized best practices, but actually challenge the fitness and safety of older placement methods altogether.
  3. 3. Best Practices: Containment Backflow Preventer Placement It seems very clear that we will not get rid of the problem of placement by ignoring the containment advocates. Advanced Metering Infrastructure (AMI) systems are revealing that more backflow is occurring at the meter than was previously believed. Its far more likely that aggressive containment rules will increase rather than decrease. The risks are finally being revealed.
  4. 4. Best Practices: Containment Backflow Preventer Placement And with this new risk realization comes a new Interested Party. The insurance company. Because of this very public commentary from experts, they now have new weapons for damage recovery.
  5. 5. Water utilities are seeking more containment backflow protection than ever before. Consider: “…. 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.…” - preamble to EPA’s Cross Connection Control Manual Best Practices: Containment Backflow Preventer Placement
  6. 6. More containment systems are being specified as RPZ, regardless of hazard threshold, than ever before. Consider: Best Practices: Containment Backflow Preventer Placement Why? • Older low hazard-use buildings with lead in every plumbing joint cannot be considered low-hazard forever. • As buildings turn over tenants, they are often transitioned from low to high hazard uses. Management and enforcement of retrofits is an extraordinary burden • Bad/ignorant actors changing plumbing systems without permits or oversight..
  7. 7. Best Practices: Containment Backflow Preventer Placement Consider: For containment, AWWA, ASPE, & the legal community recognize “outside aboveground” as best practice.
  8. 8. 1. Why outside? 2. Why not a vault? 3. Momentum: What is driving the change to better solutions? Today We’ll Cover: Best Practices: Containment Backflow Preventer Placement
  9. 9. 1. RPZs are an indoor flood hazard “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? Indoor Flood Risk.
  10. 10. Best Practices: Containment Backflow Preventer Placement Why Outside? Indoor Flood Risk. Flow Stop The most important thing a designer must understand is the worst case scenario. What can happen. What describes the ‘perfect storm? We all know that with an RPZ, when water demand stops the water between the valves often evacuates into the relief valve. Some (many) think that that event defines the limit of what water can ever flow into a drain. Not so.
  11. 11. Loss of pressure #2 valve blocked Consider a flow-stop situation, one that might naturally occur at the end of the day. If you look closely, you can see that a small pebble has lodged in the #2 check valve. Now let’s say there’s a fire around the corner that causes back siphon at this point in the system. Because the # 2 check valve is not closing, all the water that has been delivered to the building will continue to flow out the relief valve until the private lines are cleared. If this is a four story building, that’s a lot of water! Best Practices: Containment Backflow Preventer Placement Why Outside? Indoor Flood Risk.
  12. 12. #1 valve Failure Normal delivery pressure Now consider a failure of the #1 check valve. Under normal operating conditions, this failure would go unnoticed. After all, water is being called for by the user through the opening of taps. The water flows in undeterred. But with this imbalance in the system, changes in demand tend to rock the remaining valves open and closed sporadically. Demand Best Practices: Containment Backflow Preventer Placement Why Outside? Indoor Flood Risk.
  13. 13. #1 valve Failure Blockage relief valve Demand Normal delivery pressure This creates the conditions for the “perfect storm” scenario. The imbalance created by the # 1 failure makes the relief valve more prone to opening momentarily, allowing debris to block the closure of that valve. Under such conditions, a constant flow of delivered water will begin to flow directly out the relief valve. This reduces water pressure for the user, but delivery will continue. Best Practices: Containment Backflow Preventer Placement Why Outside? Indoor Flood Risk.
  14. 14. No demand Normal delivery pressure The real damage begins when the user stops using water such as at the end of a work day. With the relief valve blocked open and the # 1 valve inoperative, all the water that the purveyor can provide will flow unabated out the relief valve wherever it might be, and continue until the water source is interrupted. This is the scenario that must be avoided: the perfect storm. Best Practices: Containment Backflow Preventer Placement Why Outside? Indoor Flood Risk.
  15. 15. Best Practices: Containment Backflow Preventer Placement Why Outside? Indoor Flood Risk. This flood occurred in a hospital mechanical room causing over $1M in damage. You are looking at 2 sides of one wall. On the left, we see that the sudden water flow and volume moved the wall into the next room (right photo), which happened to be a telephone and low-voltage wiring room.
  16. 16. Best Practices: Containment Backflow Preventer Placement Why Outside? Indoor Flood Risk. The insurer sought recovery from all the risk holders including the engineer, architect, contractor, subcontractor, and even the most recent recorded tester; While the details of who paid what were not made public, we do know that the property insurer was made whole by one or more of the listed defendants.
  17. 17. So if an RPZ is designed to dump water, then drain capacity is the issue. The chart on the right is from the manufacturer of the BPA seen in the previous flood photos. It illustrates the anticipated flow rate from the relief valve at various pipe sizes and at various pressures. Note that the assembly shown will flow 375 GPM at 85 PSI. A 4” drain pipe with a 1% fall rate evacuates clean water at a maximum rate of 93 GPM. If that device is flowing at 375 GPM and your clearing 93, then you are flooding at a rate of 282 GPM. Best Practices: Containment Backflow Preventer Placement Why Outside? Indoor Flood Risk.
  18. 18. This is an article published June 2013 in the Chicago chapter of the American Society of Plumbing Engineers written by David DeBord, a former president of that organization, and current Education chair of the national ASPE. Best Practices: Containment Backflow Preventer Placement Why Outside? Indoor Flood Risk. He uses the Manufacturer’s data and he actually does the math in the article and offers FLOOD rates or 219 GPM for 2 1/2 and 3”; and flood rate of 482 GPM for 4” and above.
  19. 19. Backflow Failure Why Outside? Indoor Flood Risk. Watch this video showing a check valve failure and the resulting flood water flow. Premise Isolation: Best Practices & Standard Details
  20. 20. Charlotte: 32.000 SF Columbus: 36.000 SF Suffolk Cty: 33.333 SF Arlington: 32.000 SF Average: 33.325 SF Why Outside? Increase revenue and property value. Consider the average square footage required for just a 3-inch indoor in-line backflow preventer. To the right, four representative cities are represented. The average required space is 33.325 SF. Arlington, TX: 32 SF Best Practices: Containment Backflow Preventer Placement The space provided for an indoor BPA is routinely inadequate as provided by the architect. That’s because giving up space that would otherwise add value is being allocated as non-revenue space. Non- revenue space is the enemy of every development project. Assuming a discount rate of 9%, rent value of $30 per foot annually, and a 25 year life, the net present value of that space to the property owner is $12, 156.48.
  21. 21. NPV: Landlord has lost this amount of value by placing CBPA inside. CONSIDER: 1. If space is recaptured for rental value, what will my alternative cost be? 2. Will placing the system outside cost more or less than $12,156.48? 3. If it’s less, then how much less? (I don’t like the look of a box outside.) Why Outside? Increase revenue and property value. Assuming a discount rate of 9%, rent value of $30 per foot annually, and a 25 year life, the net present value of that space to the property owner is $12, 156.48. Annual Rent Value (based on Class A Office @ $30/sf) $999.75 25-year Cash Flows (based on 2.5% inflation) $34,149.22 Net Present Value (based on 9% discount rate) $12,156.48 Average: 33.325 SF
  22. 22. Aboveground heated enclosure for 3” BPA with heat. Option A: Use conventional model e.i., Watts 957 NRS Safe-T-Cover 300-AL-H $3,266.00 72 X 38 X 22 = 60K CI Why Outside? Increase revenue and property value. Option B: Use new ”n-type” model e.i., Watts 957N NRS Safe-T-Cover 200SN-AL-H $1,120.00 46 X 38 X 19 = 33K CI
  23. 23. $1,000 $1,120 $1,800 $3,920 plus assembly $3,266 $1,200 $1,800 $6,266 plus assembly Irrational Costs, Irrational Risks! Why Outside? Increase revenue and property value. Indoor CBPA $12,156.48 plus assembly
  24. 24. “How much more value does my building have with the additional rent?” ANSWER: Irrational Costs, Irrational Risks! Year Annual Rent* 1 $999.75 Property Value* $10,289.09 5 $1,103.54 $11,357.23 10 $1,248.55 $12,849.67 15 $1,412.62 $14,538.22 20 $1,598.25 $16,448.66 25 $1,808.27 $18,610.15 * - Today’s dollars: Assumptions: Annual rent growth of 2.5%; 5% vacancy; 35% operating expenses; capitalization rate of 6%. Owner’s Property Value Why Outside? Increase revenue and property value.
  25. 25. 1. Why outside? 2. Why not a vault? 3. Momentum: What is driving the change to better solutions? Today We’ll Cover: Best Practices: Containment Backflow Preventer Placement
  26. 26. Why not a vault? No RPZs in Vaults Best Practices: Containment Backflow Preventer Placement 41 states have written code that prohibits the installation of RPZs below grade. And as far as I know, where it remains unwritten, it is invariably enforced as an unacceptable practice.
  27. 27. We’ve all seen the extraordinary measures OSHA imposes to legally access vaults for maintenance tasks. fresh air exchange hoses, tents, extra men. The costs are more and more prohibitive but frankly, the risk of serious injury is real as well. But beyond the cost of safety for onsite workers, liability issues persist. Why not a vault? Confined Space Hazards Best Practices: Containment Backflow Preventer Placement
  28. 28. Why not a vault? Liability Best Practices: Containment Backflow Preventer Placement When a vault floods like this one, the mandatory test cocks are submerged, and in that event, a violation of the International Plumbing has already occurred. Consider what would typically make up that that water. Runoff of lawn chemicals alone make this a clear and present danger to the water supply. In fact, it led the USC Foundation of Cross Connection & Hydraulic Research in 2005 to change their recommendation of even double check BFP installation in vaults. “The foundation’s recommendation would be to install the double check valve above grade.” - USC-FCCHR “Crosstalk, Summer 2005
  29. 29. Why not a vault? Liability Best Practices: Containment Backflow Preventer Placement The foundation added stronger language in 2014. “When a backflow preventer is installed below grade, the vault or pit in which an assembly is installed may fill up with water, The water in the pit could create a cross-connection between the water in the pit and the backflow preventer through the test cocks. This may occur whether the test cocks are opened or closed….” - USC-FCCHR “Crosstalk, Summer 2014 .
  30. 30. Why not a vault? Changing Demands Best Practices: Containment Backflow Preventer Placement Buildings, through their normal life of changing tenants over time, change uses with respect to hazard levels, and hazard levels, or more precisely, the named high-hazard threshold, has become a moving target. Around the corner from our Nashville office, I snapped this picture. It sits in front of a warehouse owned by an automotive dealer. When they bought the property and erected the building, they put a double-check BFP down in that vault with the meter.
  31. 31. Why not a vault? Changing Demands Best Practices: Containment Backflow Preventer Placement A few years later, the city changed an ordinance that redefined their particular use to high-hazard. When they sought a permit to upgrade the HVAC system, the city forced them to change to an RPZ. So after constructing this huge vault, they now leave it almost empty with an RPZ in an enclosure perched on top of it. They easily paid 3X the necessary cost because they began with a “DC-only” solution. Designers need to contemplate these latter-day retrofits as they make design decisions.
  32. 32. Why not a vault? Legal Community Support Best Practices: Containment Backflow Preventer Placement Before his recent death, Indianapolis attorney Doug Cregor was the nation’s leading litigator of Cross- Connection Control cases. Douglas Cregor, Esq. “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 He was quoted in Plumbing Standards Magazine initially in 2009. I most recently saw it republished as part of a blog post on the LinkedIn Group, “MEP Engineers & Managers”: 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’.”
  33. 33. 1. Why outside? 2. Why not a vault? 3. Momentum: What is driving the change to better solutions? Today We’ll Cover: Best Practices: Containment Backflow Preventer Placement
  34. 34. Best Practices: Containment Backflow Preventer Placement This past fall at the Bi-Annual ASPE National conference, one of the learning workshops had this title. The Board President of the Central Texas ASPE, Chris Phillips, a plumbing engineer at Jacobs in SAT contacted me and asked me to deliver the message. TradeOrg.LeadershipWhereisthemomentum?
  35. 35. Best Practices: Containment Backflow Preventer Placement Seattle, WA Raleigh, NC Charlotte, VA Austin, TX Nashville, TN Albuquerque, NM Long Island, NY Denver, CO Las Vegas, NV Lynchburg, VA Columbus, OH Chicago. IL Forth Worth, TX Roswell, GA Longview, WA Arlington, TX Gwinnett City, GA Chesapeake, VA Olympia, WA Kent, WA Franklin, TN Whereisthemomentum? MoreRPZs,moreoutdoors. All these cities have made changes whereby RPZ use has been expanded either by lowering or eliminating the hazard threshold for use on domestic water lines in the past 5 years. (These are the cities we know of….)
  36. 36. Where is the momentum? Smaller solutions. 12’ 6’8” 5’2” 5’4” Best Practices: Containment Backflow Preventer Placement Consider the required enclosure for the industry standard Watts 709 DCDA on the left. It is housed by our Model 1000- AL. It’s 12 feet long and stands 6’8” tall. Compare it to the enclosure required for the Wilkins 450DA on the left. It is housed in our Model 1000TLU880M. It’s 5’4” square and stands just 5’2” tall. These two options offer the same plumbing solution and make a much smaller visual footprint.
  37. 37. Best Practices: Containment Backflow Preventer Placement Where is the momentum? Adjustments for aesthetics. AWWA has long resisted the practice of placing the BPA near the building because it increased the risk that illegal taps might occur between the meter and the BPA. But Arlington noted that all their indoor RPZs were already “living with that risk”. Enabling the enclosure to reside close to the building dramatically increases the opportunity to screen it with landscaping and thereby improve the aesthetics of the grounds. Arlington’sdecisiontoadddetailsbasedon: 1. Too much backflow detected through AMI 2. Isolation from the inspection process. 3. Non-conforming/Illegal changes after C of O 4. Subrogation risks 5. Local engineers’ survey
  38. 38. 3. CivilengineersarereadytotakeonthetaskifSDsexist Take-Aways 1. 3”andlargerCBPAsshouldnotbeinstalledindoorsandMEPsare seekingtobeexcludedfromthetask a. Indoor flood risks b. Designing for sudden flood water flows exceeds expertise 4. Water/buildingauthoritiesarefeelingpressuretoaddaboveground standarddetailssothatcivilengineerscandothisworkandimprove thesafetybyadvocatingsaferplacement Best Practices: Containment Backflow Preventer Placement 2. CBPAs should not be installed in subterranean vaults a. Contamination risks b. Probability of subsequent aboveground retrofit
  39. 39. Thank You! American Backflow Prevention Association Presentation: Backflow Installation and Design Best Practices: Containment Backflow Preventer Placement

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