Backflow Prevention Program
To assure that customers do not contaminate the water system, all industrial customers, services located on the river side of the levee, and all customers with meters 2 inches or larger are required to install a backflow preventer have it tested annually. These mechanical devices protect the water system to prevent water that is possibly impure from backing up into and contaminating the water system. Backflow Preventer Policy
For new service installation, an approved air gap or a reduced pressure backflow preventer must be installed for:
- All services 2 inches and larger.
- All industrial customers.
All reduced pressure backflow preventers must be tested at least once a year at the customer's expense by a tester / repairman that is approved by waterworks.
It shall be the duty of the customer / user at any location where backflow preventers are installed to have certified inspections and operational tests made at least once a year. In those instances where waterworks may deem necessary, more frequent certified inspections and operational tests may be required.
These inspections and tests shall be at the expense of the customer / user and shall be performed by the device manufacturer's representative or by a certified tester approved by waterworks.
The customer / user shall arrange for the inspection and tests and notify the waterworks at least 24 hours in advance so that a waterworks representative may witness the tests, if it is so desired. The backflow preventer shall be repaired, overhauled or replaced immediately at the expense of the customer / user whenever said device is found to be defective.
Copies of all records. including tests, repairs and overhauls shall be submitted to waterworks. Original copies shall be kept on file by the customer / user and shall be made available to waterworks upon request. A copy of the backflow preventer test form is available.
Services with air gaps will be confirmed annually by a superintendent. (Effective: 8-11-1981, revised: 10-01-1982.)
The following reduced pressure backflow preventers are approved for use:
||Hershey 6 Cm
||Hershey 6 Cm
||Hershey 6 Cm
Backflow preventers shall have bronze bodies and bronze or stainless steel trim. Backflow preventers 8 inches and larger shall be Watts 909 or Hershey Model 6 CM and must be epoxy coated and approved by the Department of Waterworks. (Revised: 5-27-93)
Reduced Pressure Backflow Preventer Installation Requirements
The backflow preventer must be installed as close to the meter as possible. A filter screen is required, but if a screen has been installed before the meter, an additional screen is not required.
Each backflow preventer must have an inlet and an outlet valve. All in-line equipment should be flanged or installed with union connections for easy removal during repairs or testing. Test cocks (valves) are required.
A bypass installation of any type is prohibited.
The backflow preventer shall be installed with the following clearances:
- At least 12 inches above the ground and 12 inches above the flood level, whichever is the highest.
- Not more than 30 inches above the ground or floor.
- Not less than 24 inches clearance on the side the access door or discharge valve is located. Not less than 12 inches clearance on the opposite side.
- Adequate overhead space to remove the unit for repairs.
- The installation should be in an open area that would not be flooded by a full flow relief valve discharge.
- All equipment should be protected from freezing.
- A parallel arrangement is recommended.
(Revised: 11-10-1982 )
For more detailed information and detailed diagrams, refer to: