Resolution No. 5691
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RESOLUTION NO. 5691
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A RESOLUTION OF THE CITY COUNCIL OF THE
CITY OF VERNON ADOPTING CROSS-CONNECTION
RULES AND REGULATIONS IN ORDER TO
IMPLEMENT ORDINANCE NO. 984
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WHEREAS, the City Council of the City of Vernon has
6 adopted Ordinance No. 984 enacting Chapter 25, Article V of the
7 Vernon City Code for the Protection of the Water Supply and the
8 Control of Cross-connections within the City of Vernon; and
9 WHEREAS, said Ordinance was adopted in conformity with
10 the State of California Code of RegUlations, Title 17-Public
11 Health, Sections 7583 to 7605, which authorize a program of
12 "Regulations Relating to Cross-Connections;" and
13 WHEREAS, Section 25.83 of said Ordinance provides that:
14 liThe city Council shall by resolution enact Cross-
15 Connection Rules and Regulations to implement and
16 clarify the requirements of this article regarding the
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instal.lcation, .maintenance, testing, and inspe.otion of
backflbwprevention devices. Upon approval such rules
and regulations shall have the same force and effect as
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the provisions of this ordinance."
WHEREAS, the adoption of rules and regulations to
22 prevent cross-connections will protect the health, safety, and
23 welfare of the residents, employees, and businesses of the City
24 of Vernon; and
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WHEREAS, the proposed Cross-Connection Rules and
26 Regulations have been submitted to the City Council as attached
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NOW, THEREFORE, BE IT RESOLVED BY THE CITY COUNCIL OF
THE CITY OF VERNON AS FOLLOWS:
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SECTION 1: The City Council of the City of Vernon
hereby finds and determines that the recitals contained
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hereinabove are true and correct.
SECTION 2: The City Council of the City of Vernon
hereby adopts the Cross-Connection Rules and Regulations
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attached hereto and made a part hereof by reference, which shall
be effective upon the effective date of Ordinance No. 984.
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SECTION 3: The City Clerk of the City of Vernon shall
certify to the passage of this resolution and thereupon and
thereafter the same shall be in full force and effect.
APPROvED AND ADOPTED this 21st day of November, 1989.
ATTEST: . ~
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BRUCE V. MALKENHORST , City Clerk
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STATE OF CALIFORNIA )
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COUNTY OF LOS ANGELES )
I, BRUCE V. MALKENHORST, city Clerk of the city of
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Vernon, do hereby certify that the foregoing Resolution, being
Resolution No. 5691, was duly adopted by the City Council of the
City of Vernon at a regular meeting of the City Council held on
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Tuesday, November 21.
1989 and thereafter duly signed by the
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Mayor of the City of Vernon.
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MALKENHORST, City Clerk
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BRUCE V.
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CROSS-CONNECTION RULES
AND REGULATIONS
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SECTION 1 : Definitions.
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a.
Air-Gap Set>aration (AG)
shall mean a physical break
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between a supply pipe and a receiving vessel.
The air-gap shall
be at least double the diameter of the supply pipe measured
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vertically above the top rim of the vessel, in no case less than
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one inch.
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b. Approved Backflow Prevention Device shall mean a device or
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an assembly which has passed laboratory and field evaluation
tests performed by a recognized testing organization which has
demonstrated its competency to perform such tests to the
California Department of Health Services.
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c.
Approved Water Suppl v shall mean any water supply whose
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p6tabiTity is. regulated by a state or locaJ,. h~a.lth agency.
di~,;<;Atmosphce:ri;c Va-COllum Breaker (AVB:.) s+hall mean aJilY'
11 'nonpressureassemb:l:yeontaining.a float..cheokc,a. check s~'at." apq,.,
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an airinlet}?ort.
Water flow. from a .water system through th,.is
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assembly causes the float to close the air inlet port.
stoppage
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of water flow causes the float to fall and form a check valve
against backsiphonage and also allows air to enter and satisfy
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the vacuum.
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e.
Auxiliarv Watersupplv shall mean any water supply on or
available to the premises other than the approved water supply.
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Backflow shall mean 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
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pipes of a potable supply of water from any source or sources
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other than an approved water supply source. Backsiphonage is
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one cause of backf1ow. Backpressure is another cause.
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g. Buildinq Department shall mean City of Vernon Department
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of Community Services.
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h. City shall mean the City of Vernon and its departments.
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i. contamination shall mean a degradation of the quality of
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the potable water by any foreign substance which creates a
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hazard to the public health through poisoning or through spread
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j. Critical Level (C-L) shall mean marking on a backflow
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prevention device at a point which determines the minimum
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elevation at which the device may be installed above the flood
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level rim of the fixture or receptacle served. When a backflow
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prevention device does not bear a critical level marking, the
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>k. ':crosS';';'Cdhnect;i:bn>a.s used in these Rules and Regula'tions
'shal:.ID:emean>anY'unprotected actual:or potential conne'etdort
between a potable water system used tosupplywate.r 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. By-pasS arrangements, jumper
connections, removable sections , swivel or changeover devices,
or other devices through which backflow could occur, shall be
considered to be cross-connections.
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1. Double Check-Valve Assembly (DC) shall mean an assembly
of at least two independently acting check-valves including
tightly Closing shut-off valves on each side of the check yalve
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assembly and test cocks available for testing the watertightness
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of each check valve.
Health Aqency shall mean the California Department of
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Heal th Services, or the local health agency wi th respect to a
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small water system.
Health Officer shall mean the city of Vernon Health
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Officer.
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Person shall mean an individual, corporation, company,
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association, partnership, municipality, public utility, or other
public body or institution.
Pollution shall mean an impairment of potable water to a
p.
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degree which adversely affects the aesthetic quality of water,
but does not create a hazard to the public health.
Premises shall mean any and all areas on a customer's
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property which are served or have the potential to be served by
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p l.C wa er system.
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. pressure. Vacuum Breaker (PVB) shall mean an assembly
containing an independently operating internally loaded check
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valve and an independently operating loaded air inlet valve
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located on the discharge side of the check valve.
The assembly
shall be equipped with properly located test cocks and tightly
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closing shutoff valves attached at each end of the assembly.
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s.
Public Water System shall mean 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
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of 25 individuals daily at least 60 days out of the year.
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t.
Reclaimed water shall mean wastewater which as a result of
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treatment is suitable for uses other than potable use.
u. Reduced Pressure Principle Backflow Prevention As sembI y
l.Rll shall mean an assembly incorporating two or more check
valves and an automatically operating differential relief valve
located between the two check valves, a tightly closing shut-off
valve on each side of the check valve assembly, and equipped
with necessary test cocks for testing.
v. Service Connection shall mean the point of connection
of a water user's system to the public water system.
w. Water Department shall mean the City of Vernon Water
Department.
x. Water User shall mean any person obtaining water from an
approved water supply system.
y. Water Use site shall mean a location on a water user's
system where water is utilized fOr a purpose~
Z; . ""\>Wa:te:r:User;(Ef sYstem. shall mean a system'; foX' .tbeprovj".s.ion .
Of>piped'iwa'ter..'for human'consUntption onthe...premises ,of,.a.watet';
user.
SECTION 2: Deqree of Protection
a. Types of Backflow Prevention Devices. The type of
protection provided to prevent backflow either into an approved
water supply or into a water user's system shall be commensurate
with the degree of hazard that exists at a water use site. The
types of backflow prevention devices that may be required
(listed in an increasing level of protection) include:
Atmospheric Vacuum Breaker (AVB); Pressure Vacuum Breaker (PVB);
Double Check Valve Assembly (DC); Reduced Pressure principle
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Backflow Prevention Assembly (RP); and Air-Gap Separation (AG).
The water user may choose a higher level of protection than
required by the city.
b. Minimum Protection. The minimum types of backflow
protection required to protect an approved water supply at
connections to premises with varying degrees of hazard are given
in Table 1. The minimum types of backflow protection required
to protect the water user's system, at water use sites with
varying degrees of hazard are given in Table 2. situations
which are not covered in Tables 1 and 2 shall be evaluated on a
case by case basis and the appropriate backflow protection shall
be determined by the city.
c. Multiple Service. Two or more services supplying water from
different street main~ to the same building, structure, or
premises through which an interstreet main flow may occur, shall
have/at least a .standartd' checkvalve..dneach ... water. service to>/be.
located' >adjacent'td ... and on. the property: sideiof,.the ..... respective
meters. Such check valve shall not be. considered adequate if
backflow protection is deemed necessary to protect the City's
mains from pollution or contamination; in such cases the
installation of approved backflow prevention devices at such
service connections shall be required.
SECTION 3: Installation of Baokflow Prevention Devioe at the
Servioe Conneotion
a. Backflow Prevention Device. The backflow prevention
device shall be installed in a manner prescribed in Section
7603, Title 17 of the State of California Code of Regulations.
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Location of the device shall be as close as practical to the
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water user's connection.
The city shall have the final
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authori ty in determining the required type and location of a
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backflow prevention device.
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Air-gap Separation (AG).
The air-gap separation shall be
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located on the water user's side
and as close as practical to
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the service connection.
All piping from the service connection
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to the receiving tank shall be above grade and be entirely
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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 (2) pipe
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diameters from the supply inlet, but in no case less than one
(1) inch, above the overflow rim of the receiving tank.
Water
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take-off between the water user's connection and the air-gap
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sepal:"ation shall be protected in a mannerapPl:"oved by the city.
~edt1'~ed'Press1.l!"e ) Principle Backf:low . Prevention..... AssembJ,.y,
17 .'. ifiRP)'~ '/The approved reduced pressure principle,;baekflow'
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prevention assembly shall be installed on the water user's side
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of and as close as practical to the service connection.
The
assembly shall be installed
not less than twelve inches (12 ")
above grade and not more than thirty-six inches (36") above
grade measured from the bottom of the assembly and with a
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minimum of twelve inches (12 ") side clearance.
The assembly
shall be installed so that it is readily accessible for
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maintenance and testing.
Water supplied from any point between
the service connection and the RP assembly shall be protected in
a manner approved by the city.
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d. Double Check Valve Assemblv (DC). The approved double
check valve assembly shall be located on the water user's side
of and as close as practical to the water user's connection. It
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 so that there is a minimum of six inches
(6") between the bottom of the vault and the bottom of the
assembly, so that the top of the assembly is no more than eight
inches (8") below grade, so that there is a minimum of six
inches of clearance between the side of the assembly with the
test cocks and the side of the vault, and so that there is a
minimum of three inches (311) clearance between the other side of
the assembly and the side of the vault. Special consideration
must be given to double check valve assemblies of the "Y"type.
Theseas'sem.biiesimi:ust be installed on their IIsidell with the
testscodks' in a 'Vertical position so that either check,valve
may be removed for service without removing the assembly.
Vaults which do not have an integrated bottom must. be placed on
a three inch (3") layer of gravel. Water supplied from any
point between the water user's connection and the double check
valve assembly shall be protected in a manner approved by the
city.
SECTION 4: Installation Of Backflow Prevention Devices On The
Water User's system
a. Backflow Prevention Device.
shall be installed ahead of
The backflow prevention device
a water use site which may
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contaminate or pollute the water user's system. The City shall
have the final authority in determining the required type and
location of a backflow prevention device.
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b. Accessibility. All backflow prevention devices and
assemblies shall be located so that no piping, machinery, wall
or other object blocks access to the devices or assemblies for
testing and maintenance. Any reduced pressure principle
backflow prevention assembly (RP), double check valve assembly
(DC), or pressure vacuum breaker (PVB) located in excess of 48
inches above immediately surrounding grade shall be provided a
permanent, accessible work station such as a catwalk or landing.
Work station construction must be approved by the City of
Vernon Building Department. The City shall have the final
authority in determining the required type and location of a
backflow prevention device or assembly.
c. Air-gap Separation lAG). The air-gap separation shall be
located so that the water inlet piping terminates a distance of
at least two (2) pipe diameters from the supply. inlet, but in no
'e:ase:<1ressthan one (i).. inch, above:<the . overflow ... rim of... the!
"receiving tan.k~ . Water take-off! between the..... water user~/s
connection and the air-gap separation shall be protected in a
manner approved by the City.
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21 lRP) . principle backflow
The approved reduced pressure
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prevention assembly shall be installed above grade with a
minimum clearance of twelve (12) inches between the bottom of
the assembly and immediately surrounding grade, and a minimum
three (3) inches side clearance. Water supplied from any point
between the service connection and the RP assembly shall be
protected in a manner approved by the City.
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e. Double Check Valve Assembly (DC). The approved double check
valve assembly shall be installed above grade, if possible, with
a minimum three (3) inches side clearance from walls, piping,
fences or other structures. If a double check valve assembly is
put below grade it must be installed in a vault so that there is
a minimum of six (6) inches between the bottom of the vault and
the bottom of the assembly, so that the top of the assembly is
no more than eight (8) inches below grade, so that there is a
minimum of six (6) inches of clearance between the side of the
assembly with the test cocks and tbe side of the vault, and so
that there is a minimum of three (3) inches clearance between
the other side of the assembly and the side of the vault.
Special consideration must be given to double check valve
assemblies. of the "Y"type. These assemblies must be installed
on their "side" with the tests cocks in a vertical. position so
'thateithe'f';;:cheCk.'vaTve may be. removed for .....serv.i:oe.without
removing r the. aSSembly~ Vaults which do'nothave<ani.i.ntegrated
bottom must be placed on a three (3) inch layer of gravel.
water supplied from any point between the water user's
connection and the double check valve assembly shall be
protected in a manner approved by the city.
f. Pressure Vacuum Breaker (PVB). The approved pressure vacuum
breaker shall be installed with a minimum three (3) inch
clearance between the device and any wall, fence, or other
similar structure. A pressure vacuum breaker shall also be
installed so that the Critical Level (C-L) is: (1) at least
twelve (12) inches above the highest point reached by any water
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downstream of the device, and (2) not less than twelve (12)
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inches above the surrounding grade or floor.
The pressure
vacuum breaker shall not be subjected to backpressure.
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g.
Atmospheric Vacuum Breaker (AVBl.
The atmospheric vacuum
breaker shall be located so that the critical level (C-L) is at
least six (6) inches above the highest elevation of the piping
system beyond the atmospheric vacuum breaker. Fixtures with
integral vacuum breakers manufactured and approved as a unit may
be installed in accordance with their approval requirements.
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The atmospheric vacuum breaker shall not be subjected to
backpressure.
SECTION 5:
Approved Devices and Assemblies
New Installations.
Any backflow prevention device or
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assembly installed in the City of Vernon must be listed on the
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most current "LIST OF APPROVED BACKFLOW PREVENTION ASSEMBLIES"
1.6 .pub~ished by the'Foundation for Cros's..,..connection Control ..and
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Hydraulic Research, University of Southern California.
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b.
Existinq Installations.
previously installed devices or
assemblies, not included on the "LIST OF APPROVED BACKFLOW
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ASSEMBLIES", may remain in service provided they were installed
prior to the effective date of these rules and regulations and
were annually tested after installation.
Whenever these devices
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or assemblies become unserviceable, they shall be replaced by an
approved device or assembly.
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SECTION 6:
Backflow Prevention Device Testinq and Maintenance
a.
Testinq.
The owner or controller of any premises on
which, or on account of which, backflow prevention devices are
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installed, shall have the devices tested at least annually and
immediately after installation, relocation or repair. The City
may require a more frequent testing schedule as it determines to
be necessary. No device shall be placed back in service unless
it is functioning as required. Backflow testing must be
performed by a person possessing a valid Certificate of
Competence issued by the County of LOs Angeles Health Officer.
A report in a form acceptable to the City shall be filed with
the City each time a device is tested.
b. Repair. All devices shall be serviced, overhauled, or
replaced whenever they are found to be defective and all costs
of testing, repair, and maintenance shall be borne by the water
user.
c. Procedure. The City will, by request, supply affected
water users with a list of companies which employ persons
acceptable t.ot1n'e City < to test backflow preventiondevi.ces~' The
City shall notify affected customers by mail when annual testing
of a device is needed and also supply. water users with the
necessary forms which shall be filled out each time a device is
tested or repaired.
SECTION 7: Backflow Prevention Device Removal
a. Approval. Approval shall be obtained from the City before
a backflow prevention device is removed, relocated, or replaced.
b. Removal. The use of a device shall not be discontinued
and the device removed from service except upon presentation of
sufficient evidence satisfactory to the City that a hazard no
longer exists or is not likely to be created in the future.
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c. Relocation. A device may be relocated following
confirmation by the City that the relocation will continue to
provide the required protection and satisfy installation
requirements. A retest shall be required following the
relocation of the device.
d. Repair. A device may be removed for repair upon
notification to the city, provided that either the water use is
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 shall
be required following the repair of the device.
e. Replacement. A device may be removed and replaced upon
notification to the City, provided the water use is discontinued
until the replacement device is installed. All replacement
devices shall be approved by the City and shall be commensurate
with the degree of hazard involved . A test shall be.. required
following replacement of the device.
SECTION 8: Customer Notification of Corrective Action
a. First Notice. The City shall notify the water user of
any survey of water service if the findings show corrective
action needs to be taken by the water user. A period of 60 days
will be given to complete all corrective action required
including installation of backflow prevention devices.
b. Second Notice. A second notice shall be sent to each
water user which does not take the required corrective action
prescribed. The second notice will give the water user a final
two week period to take the required corrective action. If no
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action is taken within the two week period the city may
terminate water service to the affected water user until the
required corrective action is taken.
SECTION 9: Customer Notification of Testing and Maintenance
a. First Notice. The City shall notify each affected water
user when it is time for the back.flow prevention device
installed on its premises to be tested. This wri tten notice
will give the water user 30 days to have the device tested and
will supply the water user with the necessary form to be
completed and resubmitted to the city.
b. Second Notice. A second notice shall be sent to each
water user which does not have the backflow prevention device
tested as prescribed. The second notice will give the water
user a final two week period to have the backflow prevention
device tested. If no action is taken within the two week period
the citY2ntay terlfiinate water service to the.affectedwateruser
until the subject device is tested.
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TABLE 1
TYPE OF BACKFLOW PROTECTION REQUIRED
FOR APPROVED WATER SUPPLY
DEGREE OF HAZARD
Minimum Tvne of
Backflow Prevention
a. Sewaqe and Hazardous Substances.
(1) Premises where the public water system is
used to supplement a reclaimed water supply.
There shall be no interconnection between a
potable water system and a reclaimed water
supply. . . . . . . . . . . . . . . . . .. ... .. . AG
(2) Premises where reclaimed water is used and
there is no interconnection with the potable water
system. An RP may be provided in lieu of an AG if
approved by the health agency and the City. . . . . . . . AG
(3) Premises where there is a wastewater pumping
andlor treatment plant and there is no inter-
connection with the potable water system. This
does not include a single family residence that
has a sewage lift pump. There shall be no cross-
connection between the wastewater plumbing and
the potable water supply. An RP may be provided
in lieu of an AG if it is approved by the health
agency and the City . . . . . . . .. ........ AG
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(4) Premises where hazardous substances are handled
in any manner in which the substances may enter
a potable water system. This does not include a
single family residence that has a sewage lift pump.
An RP may be provided in lieu of an AG if approved
by the health agency and the city . . . . . . . . . . . . AG
(5) Premises where there is an irrigation system into
which fertilizers, herbicides, or pesticides are, or
can be, inj ected . . . . . . . . . . . . . . . .. .. RP
b. Auxiliary Water Supplies.
(1) Premises where there is an unapproved auxiliary
water supply which is interconnected with the public
water system. An RP or a DC may be provided in lieu of
an AG, if approved by the health agency and the city. . . AG
(2) Premises where there is an unapproved auxiliary
water.supply and there is no interconnectionwith.the
public water system. A DC may be provided in.lieu of
an RP if approved by the health agency and City . ... . . RP
c. Fire Protection Systems.
(1) Premises where the fire system is directly supplied
from the public water system and there is an unapproved
auxiliary water supply on or to the premises (not
iIlterconnected) . . . . . . . . . . . . . . . .; . . . . .DC
(2) Premises where the fire system is directly supplied
from the public water system and interconnected with an
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unapproved auxiliary water supply. An RP may be provided
in lieu of an AG if approved by the health agency and
the city. . . . . . . . . . . . . . . . . .. AG
(3) Premises where the fire system is directly supplied
from the public water system and where either elevated
storage tanks or fire pumps which take suction from the
private reservoirs or tanks are used. . . . . . .. . DC
d. Restricted Access. 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. ... ......... RP
e. Prior Cross-connections. Premises which have a
repeated history of cross-connections being established
or re-established . . . . . . . . . . . . . . . . . . . . RP
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. "
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TABLE 2
TYPE OF BACKFLOW PROTECTION REQUIRED
FOR WATER USER'S SYSTEM
Dearee of Hazard
Prevention
Minimum Type of
Backflow
a. Sewaqe
(1) Water use sites directly connected to sewage. . . . . AG
(2) Water use sites indirectly connected to sewage.
An RP, PVB, or AVB may be provided in lieu of an AG
if approved by the health agency and the city . . .. AG
b. Contamination
(1) Water use sites directly connected to contaminants
and sUbject to backpressure. An RP may be provided in
lieu of an AG if approved by the health agency and the
c.i ty . . . . . . . . . . . . . . . . .. ....... AG
(2) Water use sites directly connected to contaminants and
subject to back siphonage only. An AVB may be provided in
lieu of a PVB if approved by the health agency and the
c.i ty . . . . . . . . . . . . . . .. .. ... . . . . .. . . . . PVB
(3) Water use sites indirectly connected to contaminants
and subject to back siphonage only. An AVB may be provided
in lieu of a PVB if approved by the health agency and the
ci ty . . . . . . . . . . .. . .. ... . . . . . . . PVB
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....
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c. Pollution
(1) Water use sites directly connected to pollutants
and subject to backpressure . . . . . . . . . . . .. DC
(2) water use sites directly connected to pollutants and
subject to backsiphonage only. An AVB may be provided in
lieu of a PVB if approved by the health agency and
the City . . . . . . . . . . . . . . .. . . PVB
(3) Water use sites indirectly connected to pollutants and
subject to backsiphonage only. An AVB may be provided in
lieu of a PVB if approved by the health agency and the
city. . . .. . . . . . . . . . . . . . . . .
PVB
d. Restricted Access and Prior Cross-Connections
(1) Water use sites where entry is restricted so that
inspections for cross-connections cannot be made with
sufficient frequency to assure that cross-connections
do not exist. . . . . . . . . . . . . . . . . . . . . . RP
(2)' Water use sites which have a history of cross-
connections subject to backpressure being established
or re-established. . . . . . . . . . . . . . . . . . . .
RP
(3) Water use sites which have a history of cross-
connections subject to backsiphonage being established
or re-established. . . . . . . . . . . . . . . . . .. PVB
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