The water superintendent or building official or their designee
shall be responsible for the protection of the public potable water
distribution system from contamination or pollution due to the backflow
of contaminants or pollutants through the water service connection.
If, in the judgment of said water superintendent or building official
or their designee an approved backflow-prevention assembly is required
(at the customer's water service connection; or, within the customer's
private water system) for the safety of the water system, the water
superintendent or building official or his/her designated agent shall
give notice in writing to said customer to install such an approved
backflow prevention assembly(s) at specific location(s) on his/her
premises. The customer shall immediately install such approved assembly(s)
at his/her own expense; and, failure, refusal, or inability on the
part of the customer to install, have tested, and maintain said assembly(s)
shall constitute grounds for discontinuing water service to the premises
until such requirements have been satisfactorily met.
(Ordinance adopting Code)
The water superintendent and building official in charge
of the Water Department or Code Enforcement Department of the City
of Tahoka, Texas are granted the authority and responsibility for
the implementation of an effective cross-connection control program
and for the enforcement of the provisions of this article.
Accepted by the authority responsible as meeting an applicable
specification stated or cited in this article or as suitable for the
proposed use.
Any water supply on or available to the premises other than
the city's approved public water supply. These auxiliary waters may
include water from another purveyor's public potable water supply
or any natural source(s), such as a well, spring, river, stream, harbor,
and so forth; used waters; or industrial fluids. These waters may
be contaminated or polluted, or they may be objectionable and constitute
an unacceptable water source over which the city does not have sanitary
control.
The undesirable reversal of flow in a potable water distribution
system for any reason, including a cross-connection.
A pressure, equal to or higher than the supply pressure,
caused by a pump, elevated tank, boiler, or any other means that may
cause backflow.
Backflow caused by any reason, including a negative or reduced
pressure in the supply piping.
An assembly or means designed to prevent backflow.
Air Gap.
The unobstructed vertical distance through the free atmosphere
between the lowest opening from any pipe or faucet conveying water
or waste to a tank, plumbing fixture, receptor, or other assembly
and the flood level rim of the receptacle. These vertical, physical
separations must be at least twice the diameter of the water supply
outlet, never less than 1 in. (25mm).
Reduced-Pressure Backflow-Prevention Assembly.
The approved reduced-pressure principal backflow-prevention
assembly consists of two independently acting approved check valves
together with a hydraulically operating, mechanically independent
pressure differential relief valve located between the check valves
and below the first check valve. These units are located between two
tightly closing resilient-seated shutoff valves as an assembly and
equipped with properly located resilient-seated test cocks.
Double Check Valve Assembly.
The approved double check valve assembly consists of two
internally loaded check valves, either spring loaded or internally
weighted, installed as a unit between two tightly closing resilient-seated
shutoff valves and fittings with properly located resilient-seated
test cocks. This assembly shall only be used to protect against a
non-health hazard (that is, a pollutant).
An impairment of a potable water supply by the introduction
or admission of any foreign substance that may possibly degrade the
quality and may create a potential health hazard.
A connection or potential connection between any part of
a potable water system and any other environment containing other
substances in a manner that, under any circumstances could allow such
substances to enter the potable water system. Other substances may
be gases, liquids, or solids, such as chemicals, waste products, steam,
water from other sources (potable or nonpotable), or any matter that
may adversely affect the water.
A connection between a potable water system and a nonpotable
water system with an approved backflow-prevention assembly properly
installed and maintained so that it will continuously afford the protection
commensurate with the degree of hazard.
The installation of an approved backflow-prevention assembly
at the water service connection to any customer's premises, where
it is physically and economically unfeasible to find and permanently
eliminate or control all actual or potential cross connections within
the customer's water system; or it shall mean the installation of
an approved backflow-prevention assembly on the service line leading
to and supplying a portion of a customer's water system where there
are actual or potential cross connections that cannot be effectively
eliminated or controlled at the point of the cross connection.
The term is derived from an evaluation of the potential risk
to public health and the adverse effect of the hazard upon the potable
water system.
Hazard - Health.
A cross connection or potential cross connection involving
any substance that could, if introduced in the potable water supply,
cause death, illness, spread disease, or create a risk of causing
such effects.
Hazard - Plumbing.
A plumbing-type cross connection in a consumer's potable
water system that has not been properly protected by an approved air
gap or an approved backflow-prevention assembly.
Hazard - Nonhealth.
A cross connection or potential cross connection involving
any substance that generally would not be a health hazard, but would
constitute a nuisance or be aesthetically objectionable, if introduced
into the potable water supply.
Hazard - System.
An actual or potential threat of damage to the physical properties
of the public potable water system or the consumer's potable water
system or of a pollution or contamination that would have an effect
on the quality of the potable water in the system.
Any system containing a fluid or solution that may be chemically,
biologically, or otherwise contaminated or polluted in a form or concentration,
such as would constitute a health, system, pollution, or plumbing
hazard, if introduced into an approved water supply: This may include,
but not be limited to: polluted or contaminated waters; all types
of process waters and used waters originating from the public potable
water system that may have deteriorated in sanitary quality; chemicals
in fluid form; plating acids and alkalis; circulating cooling waters
connected to an open cooling tower; and/or cooling towers that are
chemically or biologically treated or stabilized with toxic substances;
contaminated natural waters, such as wells, springs, streams, rivers,
bays harbors, seas, irrigation canals or systems, and so forth; oils,
gases, glycerine, paraffins, caustic and acid solutions, and other
liquid and gaseous fluids used in industrial or other purposes for
fire-fighting purposes.
The presence of any foreign substance in water that tends
to degrade its quality so as to constitute a nonhealth hazard or impair
the usefulness of the water.
Water that is safe for human consumption as described by
the public health authority having jurisdiction.
Water that is not safe or approved for human consumption.
The terminal end of a service connection from the public
potable water system, at its point of delivery to the customer's water
system. If a meter is installed at the end of the service connection,
then the service connection shall mean, the downstream end of the
meter. There shall be no unprotected takeoffs from the service line
ahead of any meter or backflow-prevention assembly located at the
point of delivery to the customer's water system. Service connection
shall also include water service connection from a fire hydrant and
all other temporary or emergency water service connections from the
public potable water system.
Any water supplied from a public potable water system to
a consumer's water system after it has passed through the point of
delivery.
(Ordinance adopting Code)
(a)
Water
System.
(1)
The water system shall be considered as made up of two parts: the
utility system and the customer system.
(2)
Utility system shall consist of the source facilities and the distribution
system, and shall include all those facilities of the water system
under the complete control of the city, up to the point where the
customer's system begins.
(3)
The source shall include all components of the facilities utilized
in the production, treatment, storage, and delivery of water to the
distribution system.
(4)
The distribution system shall include the network of conduits used
for the delivery of water from the source to the customer's system.
(5)
The customer's system shall include those parts of the facilities
beyond the termination of the utility distribution system that are
utilized in conveying utility-delivered domestic water to points of
use.
(b)
Policy.
(1)
No water service connection to any premises shall be installed or
maintained by the city unless the water supply is protected as required
by state laws and regulations and this article. Service of water to
any premises shall be discontinued by the city if a backflow-prevention
assembly required by this article is not installed, tested, and maintained,
or if it is found that a backflow-prevention assembly has been removed,
bypassed, or if an unprotected cross connection exists on the premises.
Service will not be restored until such conditions or defects are
corrected.
(2)
The customer's system shall be open for inspection at all reasonable
times to authorized representatives of the water or code enforcement
department to determine whether cross connections or other structural
or sanitary hazards, including violations of these regulations exist.
When such a condition becomes known, the water superintendent or building
official shall deny or immediately discontinue service to the premises
by providing for a physical break in the service line until the customer
has corrected the condition(s) in conformance with state and city
statutes and ordinances relating to plumbing and water supplies and
the regulations adopted pursuant thereto.
(3)
An approved backflow-prevention assembly shall be installed on each
service line to a customer's water system at or near the property
line or immediately inside the building being served; but in all cases,
before the first branch line leading off the service line wherever
the conditions exist:
(A)
In the case of premises having an auxiliary water supply that is
not or may not be safe bacteriological or chemical quality and that
is not acceptable as an additional source by the water superintendent
or building official, the public water system shall be protected against
backflow from the premises by installing an approved backflow-prevention
assembly in the service line, appropriate to the degree of hazard.
(B)
In the case of premises on which any industrial fluids or any other
objectionable substances are handled in such a fashion as to create
an actual or potential hazard to the public water system, the public
system shall be protected against backflow from the premises by installing
an approved backflow-prevention assembly in the service line, appropriate
to the degree of hazard. This shall include the handling of process
waters and waters originating from the utility system that have been
subject to deterioration in quality.
(C)
In the case of premises having (1) internal cross connections that
cannot be permanently corrected and controlled, or (2) intricate plumbing
and piping arrangements or where entry to all portions of the premises
is not readily accessible for inspection purposes, making it impracticable
or impossible to ascertain whether or not dangerous cross connections
exist, the public water system shall be protected against backflow
from the premises by installing an approved backflow-prevention assembly
in the service line.
(4)
The type of protective assembly required under subsections (b)(3)(A), (b)(3)(B) and (b)(3)(C) shall depend upon the degree of hazard that exists as follows:
(A)
In the case of any premises where here is an auxiliary water supply as stated in subsection (b)(3)(A) of this section and it is not subject to any of the following rules, the public water system shall be protected by an approved air-gap separation or an approved reduced-pressure principal backflow-prevention assembly.
(B)
In the case of any premises where there is water or substance that
would be objectionable but not hazardous to health, if introduced
into the public water system, the public water system shall be protected
by an approved double check value assembly.
(C)
In the case of any premises where there is any material dangerous
to health that is handled in such a fashion as to create an actual
or potential hazard to the public water system, the public water system
shall be protected by an approved air-gap separation or an approved
reduced-pressure principle backflow-prevention assembly. Examples
of premises where these conditions will exist include sewage treatment
plants, sewage pumping stations, chemical manufacturing plants, hospitals,
mortuaries, and plating plants.
(D)
In the case of any premises where there are "uncontrolled" cross
connections, either actual or potential, the public water system shall
be protected by an approved air-gap separation or an approved reduced-pressure
principle backflow-prevention assembly at the service connection.
(E)
In the case of any premises where, because of security requirements
or other prohibitions or restrictions, it is impossible or impractical
to make a complete in-plant cross-connection survey, the public water
system shall be protected against backflow from the premises by either
an approved air-gap separation or an approved reduced-pressure principle
backflow-prevention assembly on each service to the premises.
(F)
In the case of any premises where, in the opinion of the water superintendent
or building official, an undue health threat is posed because of the
presence of extremely toxic substances, the water superintendent or
building official may require an air gap at the service connection
to protect the public water system. This requirement will be at the
discretion of the water superintendent or building official and is
dependent on the degree of hazard.
(G)
Any backflow-prevention assembly required herein shall be a model
and size approved by the water superintendent or building official.
The term approved backflow prevention assembly shall mean an assembly
that has been manufactured in full conformance with the standards
established by the American Water Works Association titled:
AWWA C510-89 - Standard for Double Check Valve Backflow-Prevention,
and
AWWC C511-89 - Standard for Reduced-Pressure Principal Backflow-Prevention
Assembly,
and have met completely the laboratory and field performance
specifications of the Foundation for Cross-Connection Control and
Hydraulic Research of the University of Southern California established
by "Specification of Backflow-Prevention Assemblies" - Sec. 10 of
the most current issue of the Manual of Cross-Connection Control.
Said AWWA and FCCHR standards and specifications have been adopted
by the water superintendent or building official. Final approval shall
be evidenced by a "Certificate of Approval" issued by an approved
testing laboratory certifying full compliance with said AWWA standards
and FCCHR specifications.
The following testing laboratory has been qualified by the water
superintendent or building official to test and certify backflow preventers:
Foundation for Cross-Connection Control and Hydraulic
Research
University of Southern California
University Park
Los Angeles, CA 90089
Testing laboratories, other than the laboratory listed above,
will be approved as they become generally recognized as having met
the standards referred to above.
Backflow preventers that may be subjected to backpressure or
backsiphonage that have been fully tested and have been granted a
certificate of approval by a qualified laboratory and are listed on
the laboratory's current list of approved backflow-prevention assemblies
may be used without further testing or qualification.
(H)
It shall be the duty of the customer-user at any premises where backflow-prevention
assemblies are installed to have certified inspections and operational
tests made at least once per year by a certified Backflow-Prevention
Assembly Tester. In those instances where the water superintendent
or building official deems the hazard to be great enough, certified
inspections may be required at more frequent intervals. These inspections
and tests shall be at the expense of the water user and shall be performed
by the assembly manufacturer's representative, water department personnel,
or by a Certified Backflow-Prevention Assembly Tester approved by
the Texas Natural Resource Conservation Commission. It shall be the
duty of the water superintendent or building official to see that
these tests are made in a timely manner. The customer-user shall notify
the water superintendent or building official in advance when the
tests are to be undertaken so that the customer-user may witness the
tests if so desired. These assemblies shall be repaired, overhauled,
or replaced at the expense of the customer-user whenever said assemblies
are found to be defective. Records of such tests, repairs, and overhaul
shall be kept and made available to the water superintendent or building
official.
(I)
All presently installed backflow-prevention assemblies that do not meet the requirements of this section but were approved assemblies for the purpose described herein at the time of installation and that have been properly maintained, shall, except for the inspection and maintenance requirements under subsections (b)(4)(H), be excluded from the requirements of these rules so long as the water superintendent or building official is assured that: they will satisfactorily protect the utility system. Whenever the existing assembly is moved from the present location, requires more than minimum maintenance, or when the water superintendent or building official finds that the maintenance constitutes a hazard to health, the unit shall be replaced by an approved backflow-prevention assembly meeting the requirements of this section.
(Ordinance adopting Code)
