[R.O. 2009 §13.20.010; Ord. No. 4417 §1, 1983; Ord. No. 5202 §2, 5-4-1998]
As used in this Chapter, 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 line 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 of system, other than the public water supply,
that may be available in the building or premises or which is not
a water supply approved by the Missouri Division of Health.
The undesirable reversal of flow of water or mixtures of
water and other liquids, gases or other substances into the public
water supply from any source(s).
A device to counteract back pressures or prevent back siphonage.
Backflow caused by a pump, elevated tank, boiler or other
means that could create pressure within the system greater than the
public water supply pressure.
A form of backflow due to a negative or sub-atmospheric pressure
within a water system.
A person who has proven his/her competency to test, repair,
overhaul and make reports on backflow prevention assemblies to the
satisfaction of the Missouri Department of Natural Resources.
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. By-pass arrangements, jumper connections, removable
section, swivel or changeover devices and other temporary or permanent
devices through which, or because of which, a backflow can, or may
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 the in-line
testing of the water-tightness 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 supplied
serving one (1) single-family residence.
A device containing two (2) independently acting, internally
loaded, approved check valves together with a hydraulically operating,
mechanically independent pressure relief valve located between the
check valves. The device shall include tightly closing shutoff valves
at each end of the assembly and shall be equipped with necessary appurtenances
for in-line testing. The pressure differential relief valve shall
operate to maintain the pressure in the zone between the two (2) check
valves at least two (2) pounds per square inch less than the public
water supply pressure. 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 pressure 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.
The Missouri Department of Natural Resources.
The Board of Municipal Utilities.
[R.O. 2009 §13.20.020; Ord. No. 4417 §2, 1983; Ord. No. 5202 §2, 5-4-1998]
The purpose of this Chapter 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 the plumbing within the premises
to minimize danger of contamination of the water system on the premises
or the public water supply itself. The cross-connection control program
will comply with the provisions of the Missouri Code of State Regulations,
Title 10 CSR 60-11, Backflow Prevention.
[R.O. 2009 §13.20.030; Ord. No. 4417 §3, 1983; Ord. No. 5202 §2, 5-4-1998]
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.
[R.O. 2009 §13.20.040; Ord. No. 4417 §4, 1983; Ord. No. 5202 §2, 5-4-1998]
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.
[R.O. 2009 §13.20.050; Ord. No. 4417 §5, 1983; Ord. No. 5202 §2, 5-4-1998]
The utility shall make periodic inspections of premises served
by the public water supply to check for the presence of cross-connections.
Should such a cross-connection be found, the utility, giving the customer
not less than fifteen (15) days' notice of its intention, will discontinue
service. If an immediate hazard to health is caused by the cross-connection,
water service to the premises shall be disconnected and discontinued
until it is verified that the cross-connection has been removed.
[R.O. 2009 §13.20.060; Ord. No. 4417 §§6—11, 1983; Ord. No. 5202 §2, 5-4-1998]
A.
Backflow
prevention devices shall be installed at the service connection within
any premises where in the judgment of the utility 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 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
water supply is in compliance with local standards and is acceptable
to the utility;
2.
Premises
having internal cross-connections that are not correctable or intricate
plumbing arrangements which make it impractical 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
re-established;
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;
7.
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 utility determines no hazard exists:
a.
Hospitals,
mortuaries, clinics, medical buildings;
b.
Laboratories;
c.
Sewage
treatment plants;
d.
Food
or beverage processing plants;
e.
Chemical
plants using a water process;
f.
Metal
plating industries;
g.
Petroleum
processing or storage plants;
h.
Radioactive
material processing plants or nuclear reactors;
i.
Commercial
laundries and dye works;
j.
Paper
processing plants;
k.
Auxiliary
water systems;
l.
Cooling
systems;
m.
Farming
operations;
n.
Fire
protection systems;
o.
Sprinkler
systems filled with anti-freeze solution;
p.
Film
processing equipment;
q.
Irrigation
systems;
r.
Storage
tanks, cooling towers and circulating systems;
s.
Steam
generating systems; and
t.
Car
washes.
B.
The type
of protective device required shall be determined by the utility and
shall depend on the degree of hazard which exists. Backflow hazards
may be classified as Class I (contamination) or Class II (objectionable
substances). Protection devices required for each class are further
defined as follows:
1.
Class I backflow hazards (contamination). 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 an immediate or potential health or system hazard.
2.
Class II backflow hazards (objectionable substances). In
a case of a substance which may be objectionable but not hazardous
to health, a double check valve assembly, air-gap separation or a
reduced pressure principle backflow prevention device shall be installed.
C.
Backflow
prevention devices shall be installed on the customer water system
immediately inside the wall where the customer service line enters
the premise or at a location designated by the utility.
D.
Reduced
pressure principal backflow prevention devices shall be installed
with no plug or additional piping affixed to the pressure differential
relief valve port (except for specifically designed funnel apparatus
available from the manufacturer) and with the pressure differential
relief port a minimum of twelve (12) inches above floor or ground
level. Additionally, the assembly shall be installed at a location
where any leakage from the pressure differential relief valve port
will be noticed, that allows easy access to the assembly for maintenance
and testing and that will not subject the assembly to flooding, excessive
heat or freezing.
E.
Double
check valve backflow prevention devices shall be installed at a location
that allows easy access to the assembly for maintenance and testing
and that will not subject the assembly to excessive heat or freezing.
F.
No by-pass
piping shall be allowed around a backflow prevention assembly unless
the by-pass is equipped with an identical backflow prevention assembly.
G.
Backflow
prevention devices shall be installed at the customer's expense.
[R.O. 2009 §13.20.070; Ord. No. 4417 §12, 1983; Ord. No. 5202 §2, 5-4-1998]
Any protective device required in this Chapter shall be a model
approved by the utility and the department.
[R.O. 2009 §13.20.080; Ord. No. 4417 §13, 1983; Ord. No. 5202 §2, 5-4-1998]
Backflow prevention devices shall be inspected and tested annually
or more often where successive inspections indicate repeated failure.
The devices shall be inspected and tested at the customer's expense
and repaired or replaced and retested at the customer's expense whenever
they are found to be defective. The devices shall also be overhauled
by the customer at intervals recommended by the device manufacturer.
All such inspections, tests, repairs and overhauls shall be conducted
by a certified backflow prevention assembly tester. The original copy
of certified test results shall be forwarded to the utility within
thirty (30) days after making the inspection or test or repairs or
overhaul and retesting.
[R.O. 2009 §13.20.090; Ord. No. 4417 §14, 1983]
Failure of the customer to cooperate in the installation, maintenance,
testing or inspection of backflow prevention devices required in this
Chapter shall be grounds for the termination of water services to
the premises.
