As used in this chapter:
"Air-gap separation"
means a physical break between a supply pipe and a receiving
vessel. The air gap shall be at least double the diameter of the supply
pipe, measured vertically above the top rim of the vessel, in no case
less than one inch.
"Approved backflow prevention device"
means devices which have passed laboratory and field evaluation
tests performed by a recognized testing organization which has demonstrated
their competency to perform such tests to the California Department
of Health Services.
"Auxiliary supply"
means any water supply on or available to the premises, other
than the approved water supply.
"AWWA Standard"
means an official standard developed and approved by the
American Water Works Association ("AWWA").
"Backflow"
means a flow condition, caused by a differential in pressure,
that causes the flow of water or other liquids, gases, mixtures or
substances into the distributing pipes of a potable supply of water
from any source or sources other than an approved water supply source.
Backsiphonage is one cause of backflow. Back pressure is the other
cause.
"Contamination"
means a degradation of the quality of the potable water by
any foreign substance which creates a hazard to the public health,
or which may impair the usefulness or quality of the water.
"Cross-connection"
means any unprotected actual or potential connection between
a potable water system used to supply water for drinking purposes,
and any source or system containing unapproved water, or a substance
that is not or cannot be approved as safe, wholesome and potable.
Bypass arrangements, jumper connections, removable sections, swivel
or changeover devices, or other devices through which backflow could
occur, shall be considered to be cross-connections.
"Double check valve assembly"
means an assembly of at least two independently acting check
valves including tightly closing shutoff valves on each side of the
check valve assembly, and test cocks available for testing the watertightness
of each check valve.
"Health agency"
means the California Department of Health Services, or the
local health agency with respect to a small water system.
"Person"
means an individual, corporation, company, association, partnership,
municipality, public utility or other public body or institution.
"Premises"
means any and all areas on a customer's property which are
served or have the potential to be served by the public water system.
"Public water system"
means a system for the provision of piped water to the public
for human consumption, which has five or more service connections,
or regularly serves an average of twenty-five individuals daily at
least sixty days out of the year.
"Reclaimed water"
means a wastewater which, as a result of treatment, is suitable
for uses other than potable use.
"Reduced pressure principle backflow prevention device"
means a device incorporating two or more check valves and
an automatically operating differential relief valve located between
the two checks, a tightly-closing shutoff valve on each side of the
check valve assembly, and equipped with necessary test cocks for testing.
"Service connection"
means and refers to the point of connection of a user's piping
to the water supplier's facilities.
"Water supplier"
means the person who owns or operates the approved water
supply system.
"Water user"
means any person obtaining water from an approved water supply
system.
(Ord. 748 § 2, 1988)
It is unlawful for any person, firm or corporation at any time
to make or maintain, or cause to be made or maintained, temporarily
or permanently, for any period of time whatsoever, any cross-connection
between plumbing pipes or water fixtures being served with water by
the city of Pico Rivera (hereinafter in this chapter referred to as
"city"), and any other source of water supply, or to maintain any
sanitary fixture or other appurtenances or fixtures which by reason
of their construction may cause or allow backflow of water or other
substances into the water supply system of the city and/or the service
water pipes or fixtures of any consumer of the city.
(Ord. 748 § 1, 1988)
Backflow prevention devices shall be installed in a manner prescribed
in Section 7603, Title 22 of the
California Administrative Code. Location
of the devices should be as close as practical to the user's connection.
The city shall have the final authority in determining the required
location of a backflow prevention device.
A. Air-Gap
Separation (AG). The air-gap separation shall be located on the user's
side of and as close to the service connection as is practical. All
piping from the service connection to the receiving tank shall be
above-grade and be entirely visible. No water use shall be provided
from any point between the service connection and the air-gap separation.
The water inlet piping shall terminate a distance of at least two
pipe diameters of the supply inlet, but in no case less than one inch
above the overflow rim of the receiving tank.
B. Reduced
Pressure Principle Backflow Prevention Device (RP). The approved reduced
pressure principle backflow prevention device shall be installed on
the user's side of and as close to the service connection as is practical.
The device shall be installed a minimum of twelve inches abovegrade,
and not more than thirty-six inches above-grade, measured from the
bottom of the device, and with a minimum of twelve inches side clearance.
The device shall be installed so that it is readily accessible for
maintenance and testing. Water supplied from any point between the
service connection and the RP device shall be protected in a manner
approved by the city/district.
C. Double
Check Valve Assembly (DC). The approved double check valve assembly
shall be located as close as practical to the user's connection, and
shall be installed above-grade, if possible, and in a manner where
it is readily accessible for testing and maintenance. If a double
check valve assembly is put below grade, it must be installed in a
vault such that there is a minimum of six inches between the bottom
of the vault and the bottom of the device, so that the top of the
device is no more than a maximum of eight inches below grade, so there
is a minimum of six inches of clearance between the side of the device
with the test cocks and the side of the vault, and so there is a minimum
of three inches clearance between the other side of the device and
the side of the vault. Special consideration must be given to double
check valve assemblies of the "Y" type. These devices must be installed
on their "side," with the test cocks in a vertical position so that
either check valve may be removed for service without removing the
device. Vaults which do not have an integrated bottom must be placed
on a three-inch layer of gravel.
(Ord. 748 § 4(B), 1988)
Approval must be obtained from the city before a backflow prevention
device is removed, relocated or replaced:
A. Removal.
The use of a device may be discontinued and the device removed from
service upon presentation of sufficient evidence to the city to verify
that a hazard no longer exists or is not likely to be created in the
future;
B. Relocation.
A device may be relocated following confirmation by the city that
the relocation will continue to provide the required protection and
satisfy the installation requirement. A retest will be required following
the relocation of the device;
C. Repair.
A device may be removed for repair, provided the water use is either
discontinued until repair is completed and the device is returned
to service, or the service connection is equipped with other backflow
protection approved by the city. A retest will be required following
the repair of the device; and
D. Replacement.
A device may be removed and replaced, provided the water use is discontinued
until the replacement device is installed. All replacement devices
must be approved by the city, and must be commensurate with the degree
of hazard involved.
(Ord. 748 § 4(D), 1988)