A.Â
Where protection is required.
(1)Â
Each service connection from a public water system
for supplying water to premises having an auxiliary water supply shall
be protected against backflow of water from the premises into the
public water system, unless the auxiliary water supply is approved
as an additional source by the water district and is satisfactory
to the public health agency having jurisdiction with regard to quality
and safety.
(2)Â
Each service connection from a public water system
for supplying water to premises on which any substance is handled
under pressure in such fashion as to permit entry into the water system
shall be protected against backflow of the water from the premises
into the public system. This shall include the handling of process
waters and waters originating from the public water supply system
which may have been subject to deterioration in sanitary or chemical
quality.
(3)Â
Each service connection from a public water system
for supplying water to premises on which a substance of unusually
toxic concentration or danger to health is handled in liquid form,
even though it is not under pressure, shall be protected against backflow
of the water from premises into the public system. Examples are plating
factories using cyanide and hospitals. This is not intended to apply
to normal household installations.
(4)Â
Backflow prevention devices shall be installed on
the service connection to any premises that have internal cross-connections,
unless such cross-connections are abated to the satisfaction of the
water district.
B.Â
It shall be the responsibility of the water user to
provide and maintain these protective devices, and each one must be
of a type acceptable to the State Health Department.
The protective device required shall depend
on the degree of hazard as tabulated below:
A.Â
At the service connection to any premises where there
is an auxiliary water supply handled in a separate piping system with
no cross-connection, the public water supply shall be protected by
an approved double-check-valve assembly.
B.Â
At the service connection on any premises on which
there is an auxiliary water supply where cross-connections are known
to exist or where it is unknown if cross-connections exist, the public
water supply system shall be protected by an air-gap separation or
an approved reduced-pressure principle backflow prevention device.
C.Â
At the service connection to any premises on which
a substance that would be objectionable, but not hazardous to health
if introduced into the public water supply, is handled so as to constitute
a cross-connection, the public water supply shall be protected by
an approved doublecheck-valve assembly.
D.Â
At the service connection to any premises on which
a substance of unusual toxic concentration or danger to health is
or may be handled, but not under pressure, the public water supply
shall be protected by an air-gap separation or an approved reduced-pressure-principle
backflow prevention device. This device shall be located as close
as practicable to the water meter, and all piping between the water
meter and receiving tanks shall be entirely visible.
E.Â
At the service connection to any premises on which
any material dangerous to health, or toxic substance in toxic concentration,
is or may be handled under pressure, the public water supply shall
be protected by an air-gap separation. The air gap shall be located
as close as practicable to the water meter, and all piping between
the water, meter and receiving tanks shall be entirely visible. If
these conditions cannot reasonably be met, the public water supply
shall be protected with an approved reduced pressure-principle backflow
prevention device, provided that the alternative is acceptable to
the water district.
F.Â
At the service connection to any sewage treatment
plant or sewage pumping station, the public water supply shall be
protected by an air-gap separation. The air gap shall be located as
close as practicable to the water meter, and all piping between the
water meter and receiving tanks shall be entirely visible. If these
conditions cannot be reasonably met, the public water supply shall
be protected with an approved reduced-pressure-principle backflow
prevention device.
G.Â
If an approved single-check-valve assembly is not already installed at the service connection to any premises not covered by Subsections A through F above, then the public water supply shall be protected by the installation of an approved single-check-valve assembly at the same time a new or replacement meter is installed. It is the personal responsibility of the property owner to provide the device and see that it is installed.
A.Â
It shall be the duty of the water user on any premises
account of which backflow protective devices are installed to have
competent inspections made at least once a year, or more often in
those instances where successive inspections indicate repeated failure.
These devices shall be repaired, overhauled or replaced at the expense
of the water user whenever they are found to be defective. These tests
shall be performed by a qualified backflow prevention device tester,
and all test results will be provided to the water district within
72 hours after the test is made.
B.Â
Records of such tests, repairs and overhaul shall
also be kept and made available to the water district and the local
Health Department upon request.