Q:   What is a "cross-connection"?
       A cross-connection is a connection between a public water system or 
       consumer's potable (i.e., drinking) water system and any source or system
       containing nonpotable water or other substances.

Q:   What is the Cross-Connection Control Section?
       The Cross-Connection Control Section (CCCS) is part of the Board of Water
       Supply's Customer Care Division. It reviews constructions plans for cross-
       connection control (CCC), conducts field inspections of backflow prevention
       assembly (BFPA) installations tests the Board's own backflow prevention 
       assemblies, conducts customer education on the importance of cross-
       connection control and manages the Board's Annual Backflow Prevention
       Assembly Testing Program.

Q:   What is "backflow"? 
      Backflow is the flow of nonpotable water or other substances through a
      cross-connection and into the piping of a public water system or consumer's
      potable water system.

Q:   What is a backflow prevention assembly? 
      A backflow prevention assembly is a mechanical device installed in your private 
       property after the water meter. It prevents water already in your property pipes
       from "backflowing" into the City water system, possibly contaminating the City's
       potable water system.

Q:   Are there different types of backflow preventers?
       Yes, there are several different types of backflow preventers available:

• Air Gap (AG)
• Reduced Pressure Backflow Prevention Assembly (RP)
• Double Check Backflow Prevention Assembly (DC)
• Pressure Vacuum Breaker (PVB)
• Atmospheric Vacuum Breaker (AVB)
• Spill-Proof Pressure Vacuum Breaker (SVB)

       The Board of Water Supply recognizes all of these - except the AVB -
       as acceptable forms of cross-connection control because they can be
       tested and repaired in-line.

Q:   My backflow preventer is installed.  Now what? 
       A Certified Backflow Prevention Assembly Tester must test the device. The
      certified tester will test your new backflow prevention assembly to ensure that it
      works and will then fill out a Backflow Prevention Installation and Test form. This
      form should have been given to you that you when construction plans were
      being processed for a building permit. The Installation and Test form will be
      given to you from the Certified Tester. You must sign the bottom portion
      of the form (Assembly Owner Signature), make a copy for your records and
      mail, fax or email the completed form to:

Cross-Connection Control Section
Board of Water Supply
630 South Beretania Street
Honolulu, Hawaii 96843
FAX: (808) 550-5550
Email: cccs@hbws.org

Q:   What kinds of hazards do appropriate backflow assemblies prevent? 
       Backflow prevention controls two types of hazards: pollution and contamination
       of your drinking water supply. A pollutant is any substance which affects the
       color or odor of the water, but does not pose a health hazard. A contaminant
       causes illness or death when ingested.

Q:   Why do I have to test my backflow preventer every year?
       To ensure that the device is functioning properly. With the exception of
       the air gap, BFPAs are mechanical units that have internal seals, springs,
       and moving parts that are subject to fouling, wear, or fatigue. The annual test
       ensures a properly functioning BFPA, and certifies that the BFPA has not been
       removed or had a by-pass line installed around it. Air gaps may be tested by
       conducting a visual inspection.

Q:   Does my backflow preventer have to be installed immediately behind 
       my meter?
       No, but that is the preferred location. The backflow prevention assembly must be 
       installed on "private property." If the backflow prevention assembly cannot be
       installed immediately behind the meter, the BWS will allow the BFPA to be
       installed somewhere more convenient within the property, but the
       location must be approved by the CCCS. There can be no connections to the
       water line between the meter and the BFPA. If the water line passes through
       a landscaped area, the BWS requires the water line to be concrete jacketed.

Q:   Can my backflow preventer be installed in an underground box or vault?
       No, because this allows the assembly to become submerged in the underground
       box or vault. It also poses safety hazards to the individual testing and
       maintaining the BFPA.

Q:   What happens if I don't install a required backflow preventer?
       Failure to install the required type of BFPA could result in termination of water 
       service as indicated in the BWS Rules and Regulations Section 2-213. The Board
       of Water Supply will work with you to have the required BFPA installed.

Q:   I lost my current Backflow Prevention Assembly Test Form.  How do I 
      get another?
      Call the Cross-Connection Control Section at 748-5470 and request that a copy
      be emailed, faxed or mailed to you. You will need your water bill account number
      or the backflow preventer ID number so the correct test form can be sent to 
      you.

Q:   I'm a farmer and I want to apply for Agricultural Water Rates, what are
       the backflow requirements for my situation?
       The BWS requires a Reduced Pressure Principle Backflow Prevention Assembly
       (PR) to be installed immediately behind your meter and in front of any trees or 
       branches. The installation of the RP must be verified by one of the CCCS
       technicians prior to conversion to Agricultural Water Rate.

Q:   I have an irrigation system installed at my home; do I need to install 
      a backflow preventer?
       Cross-connection control requirements for irrigation systems serving single-family
       detached dwellings are under the jurisdiction of the City's Department of
       Planning and Permitting.

Q:   We need to install a large backflow prevention assembly, but it's ugly
       and we want to hide it from view. Is this allowed?
       Yes. The CCCS will work with you and try to find the best location or solution
       for your particular place of business.

Q:   How do I know when my device needs to be checked?
       The BWS maintains a database containing all of the permitted backflow
       devices on Oahu. When your device is due to be tested, the BWS will notify 
       you and provide you with a list of certified backflow prevention assembly
       testers. It is the customer's responsibility to schedule the test. The customer
       will also be provided with a backflow prevention device test form.

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