[R.O. 2012 § 705.290; Ord. No.
914 § 1, 9-4-1990]
As used in this Article, the following terms shall have these
prescribed meanings:
The unobstructed vertical distance through the free atmosphere
between the lowest opening from any pipe or faucet supplying water
to a tank, plumbing fixture or other device and the flood level rim
of the receptacle and shall be at least double the diameter of the
supply pipe measured vertically above the flood level rim of the vessel.
In no case shall the gap be less than one (1) inch.
Any water source or system, other than the public water supply,
that may be available in the building or premises.
Backflow caused by a pump, elevated tank, boiler or other
means that could create pressure within the system greater than the
supply pressure.
A form of backflow due to a negative or subatmospheric pressure
within a water system.
The flow, other than the intended direction of flow, of any
foreign liquids, gases or substances into the distribution system
of a public water supply.
A device to counteract back pressures or prevent back siphonage.
Any physical arrangement whereby a public water supply is
connected, directly or indirectly, with any other water supply system,
sewer, drain, conduit, pool, storage reservoir, plumbing fixture or
other device which contains or may contain contaminated water, sewage
or other waste or liquid of unknown or unsafe quality which may be
capable of imparting contamination to the public water supply as a
result of backflow. Bypass arrangements, jumper connections, removable
sections, swivel or changeover devices and other temporary or permanent
devices through which or because of which backflow could occur are
considered to be cross-connections.
An assembly composed of two (2) single, independently acting
check valves, including tightly closing shutoff valves located at
each end of the assembly and suitable connections for in-line testing
the watertightness of each check valve.
Any system of water supply intended or used for human consumption
or other domestic uses, including source, treatment, storage, transmission
and distribution facilities where water is furnished to any community,
collection or number of individuals or is made available to the public
for human consumption or domestic use, but excluding water supplies
serving one (1) single-family residence.
A device incorporating two (2) or more check valves and an
automatically operating differential relief valve located between
the two (2) checks, two (2) shutoff valves and equipped with necessary
appurtenances for in-line testing. The device shall operate to maintain
the pressure in the zone between the two (2) check valves, less than
the pressure on the public water supply side of the device. At cessation
of normal flow, the pressure between the check valves shall be less
than the supply pressure. In case of leakage of either check valve,
the differential relief valve shall operate to maintain this reduced
pressure by discharging to the atmosphere. When the inlet pressure
is two (2) pounds per square inch or less, the relief valve shall
open to the atmosphere thereby providing an air-gap in the device.
[R.O. 2012 § 705.300; Ord. No.
914 §§ 2 — 7, 9-4-1990]
A.
Purpose. The purpose of this Article is to establish a cross-connection
control program to protect the health of water consumers by the control
of actual and/or potential cross-connections through the proper installation
and surveillance of backflow prevention devices on service lines leading
to premises where cross-connections exist or are likely to occur and
through the inspection and regulation of plumbing within the premises
to minimize danger of contamination of the water system on the premises
or the public water supply itself.
B.
Application. The implementation of the program to control cross-connections
required cooperation between the customer, the department, the Health
Officer and the plumbing authority. The department has primary responsibility
to prevent contamination of the public water supply through cross-connections.
The customers served and the department are jointly responsible for
preventing contamination of the water system within the customer's
premises. An effective control program requires attention to both
of these. Backflow prevention devices are not a substitute for a continuing
and aggressive program of cross-connection investigation, surveillance
and control.
C.
Policy.
1.
These regulations will be reasonably interpreted by the department.
It is the department's intent to recognize the varying degrees of
hazard and to apply the principle that the degree of protection shall
be commensurate with the degree of hazard.
2.
All cross-connections, whether or not such cross-connections
are controlled by automatic devices such as check valves or by hand-operated
mechanisms such as gate valves or stop cocks, are hereby prohibited.
3.
Failure on the part of persons, firms or corporations to discontinue
the use of any and all cross-connections and to physically separate
such cross-connections will be sufficient cause for the discontinuance
of the public water service to the premises on which the cross-connection
exists.
4.
The department shall, in cooperation with the Health Officer
and/or the local plumbing inspection authority, make periodic inspections
of premises served by the water supply to check for the presence of
cross-connections. Any cross-connections found in such inspection
shall be ordered removed by the department. If an immediate hazard
to health is caused by the cross-connection, water service to the
premises shall be discontinued until it is verified that the cross-connection
has been removed.
[R.O. 2012 § 705.310; Ord. No.
914 § 8, 9-4-1990]
A.
Backflow prevention devices shall be installed at the service connection
or within any premises where in the judgment of the department the
nature and extent of activities on the premises or the materials used
in connection with the activities or materials stored on the premises
would present an immediate and dangerous hazard to health should a
cross-connection occur, even though such cross-connection does not
exist at the time the backflow prevention device is required to be
installed. This shall include, but not be limited to, the following
situations:
1.
Premises having an auxiliary water supply, unless the quality
of the auxiliary supply is in compliance with local standards and
is acceptable to the department.
2.
Premises having internal cross-connections that are not correctable
or intricate plumbing arrangements which make it impracticable to
ascertain whether or not cross-connections exist.
3.
Premises where entry is restricted so that inspections for cross-connections
cannot be made with sufficient frequency or at sufficiently short
notice to assure that cross-connections do not exist.
4.
Premises having a repeated history of cross-connections being
established or reestablished.
5.
Premises on which any substance is handled under pressure so
as to permit entry into the public water supply or where a cross-connection
could reasonably be expected to occur. This shall include the handling
of process waters and cooling waters.
6.
Premises where materials of a toxic or hazardous nature are
handled such that if back siphonage should occur, a serious health
hazard may result.
B.
The following types of facilities will fall into one (1) of the above
categories where a backflow prevention device is required to protect
the public water supply. A backflow prevention device shall be installed
at these facilities unless the department determines no hazard exists:
1.
Hospitals, mortuaries, clinics.
2.
Laboratories.
3.
Piers and docks.
4.
Sewage treatment plants.
5.
Food or beverage processing plants.
6.
Chemical plants using a water process.
7.
Metal plating industries.
8.
Petroleum processing or storage plants.
9.
Radioactive material processing plants or nuclear reactors.
10.
Laundry and dyeing facilities.
11.
Paper processing plants.
12.
Auxiliary water systems.
13.
Cooling systems.
14.
Farming operations.
15.
Fire protection systems.
16.
Sprinkler systems filled with antifreeze solution.
17.
Film processing equipment.
18.
Irrigation systems.
19.
Storage tanks, cooling towers and circulating systems.
20.
Steam generating systems.
[R.O. 2012 § 705.320; Ord. No.
914 §§ 9 — 16, 9-4-1990]
A.
The type of protective device required shall be determined by the
department and shall depend on the degree of hazard which exists.
B.
An air-gap separation or a reduced pressure principle backflow prevention
device shall be installed where the water supply may be contaminated
with sewage, industrial waste of a toxic nature or other contaminant
which would cause a health or system hazard.
C.
In the case of a substance which may be objectionable but not hazardous
to health, a double-check valve assembly, air-gap separation or reduced
pressure principle backflow prevention device shall be installed.
D.
Backflow prevention devices shall be installed at the meter or at
a location designated by the department. The device shall be located
so as to be readily accessible for maintenance and testing and where
no part of the device will be submerged.
E.
Backflow prevention devices shall be installed by the department
at the customer's expense.
F.
Any protective device required in this Section shall be a model approved
by the department. A double check valve assembly or a reduced pressure
principle backflow prevention device will be approved if it has successfully
passed performance test of the University of Southern California Engineering
Center and other testing laboratories satisfactory to the department.
G.
Backflow prevention devices shall be annually inspected and tested
by the department at the customer's expense or more often where successive
inspections indicate repeated failure. The devices shall be repaired,
overhauled or replaced by the department at the customer's expense
whenever they are found to be defective. Inspections, tests and repairs
and records thereof shall be performed by the department at the customer's
expense.
H.
Failure of the customer to cooperate in the installation, maintenance,
testing or inspection of backflow prevention devices required in this
Section shall be grounds for the termination of water service to the
premises.
