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Commission Memorandum
REPORT TO: Honorable Mayor and City Commission
FROM: Brian Heaston, Project Engineer
Debbie Arkell, Director of Public Services
Rick Moroney, Water Treatment Plant Superintendent
SUBJECT: Periodic report regarding status, cost, and progress of community water
fluoridation practices of the City of Bozeman water supply and distribution system as required
by Commission Resolution 741.
MEETING DATE: August 1, 2011
AGENDA ITEM TYPE: Consent Item
RECOMMENDATION: Accept the periodic report presented by city staff in this
Commission Memorandum concerning the current state of community water fluoridation of the
City of Bozeman public water supply and distribution system and recognize the proposed
recommendation of the U.S. Department of Health and Human Services (HHS) to limit fluoride
concentrations in community water systems to a value of 0.7 parts fluoride to one-million parts
water (0.7 ppm or mg/l) and furthermore direct city staff to continue its community water
fluoridation practices by adding fluoride to the water supply and distribution system at the
recommended limits as they are periodically established by the HHS, or any other agency having
regulatory authority.
BACKGROUND: Commission Resolution 741, passed July 1, 1953, establishes community
water fluoridation for the City of Bozeman water supply and distribution system. The resolution
requires the addition of fluoride to the community water system to attain a value of 1.0 parts
fluoride to one-million parts water (1.0 ppm or mg/l) and recognizes that this value may, from
time to time, be subject to change if ordered by the Board of Health of the State of Montana.
The resolution further directs the City Manager to make periodic reports to the City Commission
concerning the status, cost, and progress of such service.
Community water fluoridation is a voluntary public health initiative promoted by the HHS
Center for Disease Control and Prevention (CDC). Neither the CDC, nor the State of Montana,
requires community water systems to be fluoridated. In Montana, fluoridation is a community-
based decision made at the local level. Water systems that do elect to fluoridate are subject to
system design rules and reporting requirements of the Montana Department of Environmental
Quality. As mentioned above, the City of Bozeman has fluoridated its water system since 1953
with the passage of Commission Resolution 741.
Community water fluoridation prevents tooth decay and reduces the prevalence of dental caries
(cavaties) by providing frequent contact of teeth to fluoride ion at low concentrations. Water
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fluoridation is an inexpensive option to deliver oral health benefits to all residents of a
community regardless of their socioeconomic condition. According to the CDC, for every $1
invested in fluoridation, a savings of $38 is realized in preventive dental treatment costs.
Furthermore, the CDC has recognized water fluoridation as one of 10 great public health
achievements of the 20th century. According to national statistics compiled in 2008, 72.4% of
the U.S. population served by community water systems received fluoridated water, or roughly
195.5 million individuals. In Montana, fluoride addition is limited to the seven communities:
Bozeman, Chester, Colstrip, Hardin, Laurel, Miles City, and Scobey.
Community water fluoridation is not without controversy. Fluoride is available in many dental
hygiene products (fluoride toothpaste, mouth rinse, etc), is added to some bottled water, and
dentist-applied topical fluoride treatments are available. Excessive quantities of fluoride can
cause dental fluorosis, which is a staining and pitting of the tooth surface – principally a
cosmetic defect. Young children are particularly susceptible to dental fluorosis during the teeth-
forming stages of childhood. Furthermore, prolonged exposure to excessive fluoride
concentrations may result in chronic fluoride toxicity causing skeletal fluorosis exhibited by
symptoms of weakened bones and adverse effects on the kidneys, amongst other negative
effects. With other forms of fluoride readily available to consumers, controversy surrounds the
question of whether the oral health benefits of fluoride are better administered by the individual
as a personal health choice, or through local governance in the management of its public water
system.
The CDC is currently revisiting its recommended fluoride limits for community water
fluoridation, as fluoride products are now readily available on the oral health market. At present,
the CDC recommends adding fluoride at a dosing limit of 0.7 – 1.2 parts fluoride per one-million
parts water (ppm). The city’s policy is established at 1.0 ppm fluoride concentration per
Commission Resolution 741 (passed 1953). The CDC’s proposed recommended fluoride limit is
set at 0.7 ppm. The CDC is currently reviewing public comments received in response to the
recommended revisions to community water fluoridation limits. The agency expects to release
its final recommended level towards the beginning of 2012.
City staff contacted the Gallatin City-County Health Department (GCCHD) regarding the
proposed 0.7 ppm fluoride limit contemplated by CDC to obtain their opinion on the matter.
GCCHD subsequently contacted local health providers requesting their input. Community
Health Partners acknowledged their support of the adjusted fluoride limit. Furthermore, Dr. Jane
Gillette, of Mint Dental Studio, indicated that the American Dental Association, the Montana
Dental Association, and the 6th District Dental Society (Gallatin & Park Counties) all support the
CDC in their proposed fluoride recommendation. Notwithstanding support from local, regional,
and national health providers and associations, Rick Moroney, City of Bozeman Water
Treatment Plant Superintendent, has received sporadic public comments from individual
community members opposed to the city’s fluoridation practices.
Ultimately, the decision to fluoridate the city’s public water supply is the decision of the City
Commission. Staff recommends maintaining the current status quo of 1.0 ppm fluoride addition
to the public water supply, with the understanding that once the currently proposed 0.7 ppm limit
of the CDC becomes officially recognized, that the city will reduce its fluoride addition to this
new 0.7 ppm recommended value. The proposed motion for this consent agenda item captures
this caveat. It furthermore will allow administrative changes to the dosing limit if and when the
recommended fluoride limit is revised at a future date, or falls under the jurisdiction of any other
public agency (e.g. the Montana Department of Environmental Quality, Montana Department of
Public Health and Human Services, etc.).
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Current State of Technical Operations of City of Bozeman Water Fluoridation
Fluoride is present naturally in the raw water supplies of the City of Bozeman (Lyman Creek,
Sourdough Creek and Hyalite Creek). Background concentrations vary seasonally, typically
ranging from 0.1 – 0.35 parts fluoride per one-million parts water (ppm). Raw water samples are
tested every 15 days at Lyman Creek and combined Sourdough/Hyalite raw water to determine
the concentration of natural fluoride in these sources. This value is then subtracted from the 1.0
ppm fluoride dosing target to determine the quantity of additional fluoride needed to supplement
the system in order to raise the fluoride concentration of water placed into the distribution system
to the targeted 1.0 ppm level. Separate fluoride feed systems are employed at the Lyman Creek
treatment plant and the Sourdough treatment plant. The dosing calculation takes system demand,
purity and percent fluoride ion in the respective fluoride products into account.
At the Lyman Creek water plant, the fluoride product used is liquid hydrofluorosilicic acid. The
chemical is supplied through Thatcher Chemical Company’s Missoula terminal, although other
vendors have been used in the past. The product is certified for use in potable water through the
National Science Foundation (NSF). This acid is very dangerous as fluoride ion is an extremely
powerful oxidizer so protective clothing must be worn while handling it. The product is metered
into the finished effluent as it leaves Lyman Reservoir through a peristaltic pump that is
controlled through a flow meter and Programmable Logic Controller (PLC) arrangement,
according to distribution system demand. The PLC communicates through a Supervisory
Control and Data Acquisition (SCADA) system with the Human Machine Interface (HMI)
employed at the Sourdough water treatment plant. The desired fluoride dosage limit (1.0 ppm
minus measured background fluoride concentration) is set to result in the targeted 1.0 ppm
dosage input at the HMI. The dosage limit is changed every fifteen days, or more often, if
quality control tests dictate.
The fluoride product used at the Sourdough plant is sodium silicofluoride, which is a solid
ground to powdered form. This product presents inhalation hazards to treatment plant operators
requiring the use of supplied air when working with the product. The product is presently
purchased from Hawkins Chemical Company’s Billings terminal and is certified for potable
water use through the NSF. The process employed to add the product to the Sourdough effluent
is similar to that used at Lyman, however it is less automated. Because the product is added in
solid form, a volumetric feeder is used. Manual adjustment to the feeder is required with each
change to the effluent flow rate leaving the Sourdough plant. The feeder is calibrated for
accuracy at least every thirty days.
Quality control procedures are in place in the day to day fluoride operations of the Lyman and
Sourdough treatment plants. Each day at midnight, a fluoride dosage is calculated according to
the respective products used at each plant. Daily water samples are taken from at least eight
sampling locations within the water distribution system in town. Each sample is then tested daily
to ensure the desired 1.0 ppm targeted fluoride concentration is met. These sampling results are
forwarded to the Public Water Supply Section of the Montana Department of Environmental
Quality to ensure reporting requirements are satisfied.
During a typical year, approximately $35,000 in chemical cost is expended to supply products to
the respective the fluoride feed systems used at the Lyman and Sourdough plants
(hydrofluorosilicic acid for Lyman at $24,000; sodium silicofluoride for Sourdough at $11,000).
Maintenance cost on these systems is nominal.
ALTERNATIVES: Should the Commission decide to not maintain the status quo and
furthermore recognize the 0.7 ppm recommended fluoride dosing limit of the CDC, the issue of
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community water fluoridation can be scheduled for public hearing to debate the merits and
controversies surrounding the practice in general. The Commission could also choose to place
the issue on the public ballot for the coming general election or could hold a special election.
Lastly, the Commission could decide to cease fluoride addition by revoking Resolution 741,
wherein the background fluoride concentrations present in the city’s raw water sources would
pervade the water distribution system.
FISCAL EFFECTS: If the status quo is maintained (and the CDC recommended fluoride limit
of 0.7 ppm is put into use once officially recognized) a 30% reduction in annual chemical costs is
reasonably expected, saving the city approximately $10,500 annually. Should the Commission
decide to cease fluoridation practices, $35,000 of annual savings will be realized. Furthermore,
the fluoride feed system to be constructed with the new Sourdough membrane filtration plant
could be removed from the construction contract to save the capitalization expense for this new
system.
Attachments: Commission Resolution 741
Report compiled on: July 21, 2011
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374
COMMISSION RESOLUTION NO 741
A RESOLUTION OF THE CITY COMMISSION OF THE CITY OF BOZEMAN MONTANA PROVIDING FOR THE INTRO
DUCTION OF FLUORINE INID THE DRINKING WATER SuPPLY SYSTEM OF THE CITY OF BOZEMAN
WHEREAS It appears to be the consensus of scientifio medical opinion that the presence of fluorine
in drinking water is a deterrent to tooth decay and
WEEREAS Such chemical element is not found in a high enough concentration in the natural supply of
water distributed to the oitizens of this City and IWHEREASFluoridationofdrinkingwaterundersuohconditionsasexistinthismunicipalityhasbeen
endorsed by the Board of Health o the State of Montana and
WBEREAS Fluoridation of drinking water wi thin the City of Bozeman and the equipment therefor as
installed in said City of Bozeman have been approved by the Board of Health of the State of Montana
and
WHEREAS It has been determined on the basis of study and investigation made by the City Commission
of the City of Bozeman that fluorine can be introduced into the drinking water supply o the said City
of Bozeman as a measure to promote the publio health and welfare of the inhabitants of said City
NOW THEREFORE BE IT RESOLVED BY THE COMMISSION OF THE CITY OF BOZEMAN
Section 1
That the City Manager of the City of Bozeman be and he is hereby authorized and directed to provide
the means and to prooeed with the introduction of fluorine into the public water supply furnished within
this municipality in such quantities as are required to maintain throughout the piped distribution
system fluorine concentration of approximately one 1 part of fluorine to each one l million parts
of water or in such concentration as may be ordered rom time to time by the Board of Health of the
State of Montana ISection2
That the City Manager is hereby direoted to make periodic reports to the City Commission as to
the status cost and progress of such service
Section 3
This Resolution shall be in force and effect immediately from and after its passage and adoption
Passed and adopted by the Commission of the City of Bozeman at a regular session thereof held on
July 1 1953
Attest
Vtl
C ar of t e ity Commisnon Mayor
Sta t e of M m tana
8S
County of Gallatin
I L G Shadol1n Clerk of the Commission of The Citof Bozwnan do hor y certify IthrttheforogongCommissinResolutionNo7blwaspublishedbytitleandnumberinthe
Bozeman Daily Chronicle 8 newspBper of generDl circualtlonprinted and published in said
City in the issue of July 3rd 1953 and thft due proof of such publication is on f Ue
in my office
IN WITNESS 1EPEOF I hereunto set my hand and affix the corporEte seal of my o fice
tlis 6th day of Tu17r 1953
ClerIc 0 f the City Comrnis s i m
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