Cross-Connection Control and Backflow Prevention Program

1
CROSS-CONNECTION CONTROL AND BACKFLOW PREVENTION

• The WHYs and HOWs

PREPARED FOR THE TOWN OF QUANTICO
BY
RGS ENTERPRISES ROBERT G SAMPSON 28 WOODVIEW DR.
FREDERICKSBURG, VA. [phone]
2
Legal requirements

• EPA Safe Drinking Water Act 1974 (latest
  amendment 1996)
• IL Health/Plumbing Codes (Sections dealing with
  cross-connections/backflow protection)
• TITLE 77PUBLIC HEALTH
• CHAPTER 1 DEPT. PUBLIC
• HEALTH
• SUBCHAPTER WATER SEWAGE
• OSHA 1926.51 (b) (2)

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What is cross-connection program and why is it
important?

• The purpose of this program is for the health and
  welfare of the citizens of The Town Of Quantico
  by ensuring that the Towns drinking water supply
  is protected from harmful substances.
• Cross-Connection Control is the methods,
  practices, and procedures used to prevent
  contamination and pollution of drinking water
  from backflow.
• Cross-Connection Control is important as that
  ensures that your drinking water remains safe
  from bacteria, chemicals, and other substances
  that may enter the water from unknown or
  improperly maintained sources because of abnormal
  pressure changes.

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PURPOSE OF CROSS-CONNECTION BACKFLOW PROGRAM

• The Purpose Of This Program Is To Protect The
  Health And Welfare Of The Citizens Of THE TOWN OF
  QUANTICO By Ensuring That The Town's Drinking
  Water Is Protected From Harmful Substances. It
  Is Also Required By The Virginia Department Of
  Healths (VDH) Waterworks Regulations.
• A Cross-Connection Control Program is a written
  plan developed to detect, monitor, and manage
  cross-connections and implement the procedures
  and practices necessary to ensure safe drinking
  water and comply with the rules and regulations
  of federal, state and local governments.
• The Town of Quantico shows a commitment to
  providing its citizens with superior drinking
  water by developing its Cross-Connection Backflow
  Program. This program is essential to ensure
  quality, safe drinking water. With your help, we
  can make this program efficient and successful.

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WHY SHOULD YOU INVEST IN A BACKFLOW PROGRAM

• Backflow Events Occur Every Day In All Types Of
  Water Systems.
• People Become Sick Or Ill From These Events.
• Your Water System Quality Can Be Trashed In Just
  A Few Moments.
• Prevention Is Very Cost Effective
• It Takes Only A Little Structure To Prevent
  Backflow
• BACKFLOW INCIDENTS CAN COST MILLIONS!

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WHO DOES WHAT FOR THE PROGRAM

• TOWN
• Have a simple and clear backflow program.
• Statement in customer contract requiring backflow
  compliance as a term of service.
• All single family houses to have a dual check
  valve all other connections to have a Reduced
  pressure device.
• Send letters which educates as well as reminds
  the customer of obligation.
• Provide a list of approved testers.
• Track compliance and document your program.
• A water system may chose to offer in-house
  testing.

• CUSTOMER
• Customer installs, owns and pays for annual
  testing by a certified tester.
• If the backflow preventer device should fail
  testing, the customer pays to have it repaired
  and retested.

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A cross-connection is any existing or possible
interconnection between a public water system or
consumers potable (i.e., drinking) water system
and any other system containing substances of
unknown or uncertain quality. A cross connection
is described as the link that can bring two
systems together.
WHAT IS A CROSS-CONNECTION
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• WHAT IS CONTAMINATION?
• It is the introduction or presence of any foreign
  substance in a drinking-water system that could
  or does make the water hazardous to human health.
• WHAT IS POLLUTION?
• It is the introduction or presence of any foreign
  substance in a drinking-water system that could
  or does change the taste, odor, or color of the
  water and weakens its usefulness, but is not
  hazardous to human health.
• WHAT IS POTABLE WATER?
• Water that is fit for drinking, cooking and
  household uses is called potable water.

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Common cross-connections

• Where are the most common cross-connections
  found?
• Whenever a plumbing fixture is connected to the
  drinking water supply, a potential
  cross-connection exists. Fortunately, many of
  the plumbing fixtures have built-in backflow
  protection. Here are a few examples of
  cross-connections that could lead to backflow
• Wash basins and service sinks
• Laboratory equipment
• Irrigation or lawn sprinkler systems
• Swimming Pools or Spas
• Solar Heat Systems
• Fire Sprinkler Systems
• Auxiliary Water Supplies (wells, storage tanks
  and second feeds)
• Photo development equipment
• Chemical feed equipment
• Attachment to hoses to apply weed killer or
  fertilizer or to flush antifreeze
• Food and Beverage Processing Equipment
• Ornamental Fountains
• Boilers
• Hose Bibs

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Other typical cross-connections

• APARTMENTS
• Laundry Tub Faucets
• Hose Faucets
• Boilers
• OFFICE BUILDINGS
• Boilers
• Chillers
• Soap Dispensers
• Water Closets
• Coffee Makers
• RESTAURANTS
• Beverage Dispensers
• Food Grinders
• Dishwasher
• Glass Washer
• Soap Dispenser
• Hose and Spray

• MANUFACTURING PLANTS
• Chemical Dispensers
• Cooling Towers
• Boilers
• Hose Faucets
• Equipment Using Potable Water

In Restaurants, beverage dispensing equipment are
required to have specialized backflow prevention
device installed to prevent carbon dioxide gas
and carbonated water from mixing with copper
piping. In other types of commercial and
industrial businesses, it is necessary to ensure
the safety of our drinking water by requiring the
installation of backflow prevention assemblies in
the main-service line to certain types of
buildings, such as hospitals, medical and dental
offices, veterinary facilities, funeral homes,
industrial manufactures, chemical and petroleum
processing and storage facilities, car washes,
laundries, etc.
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Types of cross connections

• Back pressure

• backflow

• Backsiphonage

• Is The Backward Flow Of Water Or Other Substance
  From One System To Another Because Of An Increase
  In Pressure. The Water or Substance Is Pushed
  Backward Suddenly Or Over Time By A Pump, An
  Increase In Temperature Or Because Of Changes In
  Height (Pressure Increases As Water Rises).

• Is Caused By Negative Pressure (Vacuum) In The
  Supply Line. This Effect Is Similar To Sipping A
  Coke By Inhaling Through A Straw, Which Induces A
  Flow In The Opposite Direction. Causes Are When
  The Water Or Substance Is Drawn Backward To The
  Lowest Point Such As Opening A Fire Hydrant Or A
  Break In A Pipe Of The Water Main.

• Is The Undesirable Reversal Of Flow Of Water Or
  Other Substances Or Mixtures Into The Drinking
  Water Distribution System.
• BACKFLOW can occur in two ways
• BACKSIPHONAGE OR BACKPRESSURE.

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Why do water suppliers need to control
cross-connections and protect their public water
systems against backflow?

• Backflow into a public water system can pollute
  or contaminate the water in that system (i.e.,
  backflow into a public water system can make the
  water in that system unusable or unsafe to
  drink), and each water supplier has a
  responsibility to provide water that is usable
  and safe to drink under all foreseeable
  circumstances. Furthermore, consumers generally
  have absolute faith that water delivered to them
  through a public water system is always safe to
  drink. For these reasons, each water supplier
  must take reasonable precautions to protect its
  public water system against backflow.

Contaminated water has to be boiled before safe
to drink.
Clean water is GOOD for you!
The signs of drinking water contaminants are not
always obvious. Contaminated water may not
taste, smell or look any differently than safe
drinking water. YOU are responsible for the water
your family drinks.
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What should water suppliers do to control
cross-connections and protect their public water
systems against backflow?

• Water suppliers usually do not have the authority
  or capability to repeatedly inspect every
  consumers premises for cross-connections and
  backflow protection. Alternatively, each water
  supplier should ensure that a proper backflow
  preventer is installed and maintained at the
  water service connection each dedicated fire
  protection system or irrigation piping system and
  the water service connection to each of the
  following types of premises 1) premises with an
  auxiliary or reclaimed water system
  2)industrial, medical, laboratory, marine or
  other facilities where objectionable substances
  are handled in a way that could cause pollution
  or contamination of the public water system 3)
  premises exempt from the state plumbing Code and
  premises where an internal backflow preventer
  required under the State Pluming Code is not
  properly installed or maintained 4)classified or
  restricted facilities and 5)tall buildings.
  Each water supplier should also ensure that a
  proper backflow preventer is installed and
  maintained at each water loading station owned or
  operated by the water supplier.

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Backflow protection

• Is the use of
• Backflow
• preventers

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What is a backflow preventer?

• A Backflow preventer is a means or mechanism to
  prevent backflow. The basic mechanism for
  preventing backflow is a mechanical backflow
  preventer, which provides the physical barrier to
  backflow.

• There are six basic devices that are used to
  protect against cross connections. They are
• Air gaps
• Atmospheric vacuum breakers
• Pressure vacuum breakers (pvb)
• Dual or double check valves (dc)
• reduced-pressure principle backflow preventers
  (rp)
• Residential dual check valve (rdc)

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What is an air gap?

• An air gap is a vertical, physical separation
  between the end of a water supply outlet and the
  flood-level rim of a receiving vessel. This
  separation must be a least twice the diameter of
  the water supply outlet and never less than one
  inch. An air gap is considered the maximum
  protection available against backpressure
  backflow or backsiphonage but is not always
  practical and can easily be bypassed.

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Atmospheric vacuum breakers

• An Atmospheric Vacuum Breaker (AVB) Is A Backflow
  Prevention Device Used In Plumbing To Prevent
  Backflow Of Non-potable Liquids Into The Drinking
  Water System. It Is Usually Constructed Of Brass
  And Resembles A 90-degree Elbow With A Hood On
  Its Top To Allow Air To Enter The Water System If
  A Siphon Attempts To Form. Inside This Elbow Is A
  Poppet Valve That Is Held "Up" By The Water
  Pressure Found In The System, Closing The Air
  Entrance To The Device. If The Pressure In The
  "Upstream Side" Is Reduced To Atmospheric
  Pressure Or Below, The Poppet Valve Drops And
  Allows Air To Enter The System, Breaking The
  Siphon.

One-Inch Brass Atmospheric Vacuum
Breaker mounted on PVC Pipe
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What is a pressure vacuum breaker assembly PVB)?

• A PVB is a mechanical backflow preventer that
  consists of an independently acting,
  spring-loaded check valve and an independently
  acting, spring-loaded, air inlet valve on the
  discharge side of the check valve. It includes
  shutoff valves at each end of the assembly and is
  equipped with test cocks. A PVB may be used to
  isolate health or non-health hazards but is
  effective against backsiphonage only

• .

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What is a dual check (double check) valve
assembly (DC)?

• A DC is a mechanical backflow preventer that
  consists of two independently acting,
  spring-loaded check valves. It includes shutoff
  valves at each end of the assembly and is
  equipped with test cocks. A DC is effective
  against backpressure backflow and backsiphonage
  but should be used to isolate only non-health
  hazards.

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What is a reduced principle assembly (RP)?

• An RP is a mechanical backflow preventer that
  consists of two independently acting,
  spring-loaded check valves with a hydraulically
  operating, mechanically independent,
  spring-loaded pressure differential relief valve
  between the check valves and below the first
  check valve. It includes shutoff valves at each
  end of the assembly and is equipped with test
  cocks. An RP is effective against backpressure
  backflow and backsiphonage and may be used to
  isolate health or non-health hazards.

21
What is a residential dual check valve (rdc)?

• A rdc is similar to a DC in that it is a
  mechanical backflow preventer consisting of two
  independently acting spring-loaded check valves.
  However, it usually does not include shutoff
  valves, may or may not be equipped with test
  cocks, or ports, and is generally less reliable
  than a DC. A rdc is effective against
  backpressure backflow and backsiphonage but
  should be used to isolate only non-health hazards
  and is intended for use only in water service
  connections to single-family homes.

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Hose bib

• The most common cross-connection is an outside
  hose faucet, typically called a Hose Bib.
• These plumbing fixtures are used for connecting
  hoses that we use for various purposes such as
  watering our gardens, flowers and lawns. Also
  used for washing the car or dog or refilling a
  pool.
• All hose bibs (hose connections) are required by
  code to have a special backflow prevention device
  called a hose connection vacuum breaker. This
  device prevents water in the hose from flowing
  backward into the pipes of your home.

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Are all residential homes required to have
backflow assemblies?

• At This Time Only Those Residential Homes That
  Have Irrigation, Sprinkler Systems, Boilers,
  Geothermal Heating Systems Or Medical Equipment
  Connected To The Towns Water System  Are
  Required To Have Backflow Assemblies.
• Have you ever connected a garden sprayer to the
  end of a hose in order to fertilize your
  vegetables or flowers? Many of us do.
• Have you ever stuck the end of a garden hose into
  your cars radiator or connected it to the heater
  hoses in order to flush the radiator?
• Or, have you ever placed the hose under the
  waters surface in a swimming pool and left it
  on?
• Doing any of the above poses a risk of
  contaminating your homes drinking water with
  chemicals that can cause serious health concerns
  if swallowed.

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Why do backflow preventers have to be tested
yearly?

• Mechanical Backflow Preventers Have Internal
  Seals, Springs, And Moving Parts That Are Subject
  To Failing, Wear, Or Fatigue, Which Is Why VDH
  Requires That They Be Tested At Least Annually.
  This Requirement Is Echoed By Virginia
  Maintenance Code, International Plumbing Code,
  And The Environmental Protection Agencys (EPA)
  Cross Connection Control Manual.
• Mechanical Backflow Preventers And Air Gaps Can
  Be Bypassed. Testing Ensures That They Are
  Functioning Properly. A Visual Check Of Air Gaps
  Is Sufficient, But Mechanical Backflow Preventers
  Have To Be Tested With Properly Calibrated Gauge
  Equipment By Someone Who Holds A Current
  Certification (License) As A Backflow Prevention
  Device Worker Issued By The Virginia Department
  Of Professional And Occupational Regulation. The
  License Is Renewed Yearly. There Is No Control
  Over Cost Of The Testing. Testers Set Their Own
  Prices Which Are Usually Controlled By The
  Current Market. The Charges Can Range From 80 -
  200 Depending Upon The Region.

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Where can I get more information about
cross-connection control?

• Obtaining more information, including the types
  of problems that can and have been caused by
  Cross-Connections and Backflow, the principles of
  water pressure and backflow, and additional
  examples of assemblies and devices, can be found
  at http//www.epa.gov/safewater/crossconnection.h
  tml
• One Excellent Reference Manual Is The Ninth
  (1993) Edition Of The University Of Southern
  Californias Manual Of Cross-connection Control,
  Which Is Available From The Foundation For
  Cross-connection Control And Hydraulic Research
  University Of Southern California KAP-200
  University Park MC-2531
• Los Angeles, California 90089-2531 (213)
  740-2032 Http//Www.Usc.Edu/Dept/Fccchr
• Another Excellent Reference Manual Is The Second
  (1990) Edition Of The American Water Works
  Associations (AWWA) Manual M14, Recommended
  Practice For Backflow Prevention And
  Cross-connection Control, Which Is Available From
  The AWWA Bookstore 6666 West Quincy Avenue
  Denver, Colorado 80234 [phone]
  Http//Www.Awwa.Org
•