Memo to City Councilors, Staff, and Citizens
RE: Fluoride removal
There has been considerable discussion regarding the proposed removal of fluoride from the City of
Cheney’s water system. I would like to provide some additional information and context regarding the
current system, the condition of the existing fluoridation equipment, and the factors considered in
making this recommendation.
The City of Cheney water system is currently supplied by six operating wells, with an additional well
offline due to PFAS contamination. There is another well that is currently used only for irrigation for a
total of 8 wells in the system. Analysis of untreated water at each source shows naturally occurring
fluoride levels of about 0.3 mg/L. In the early 1970s, each well was equipped with a fluoride injection
system designed to add sodium fluoride into the water supply at each source when the pumps are
running. The current DOH guidelines define the target concentration of fluoride to be 0.7 mg/L with an
allowable range of 0.5-0.9 mg/L. This range is lower and narrower than the design parameters of the
original system.
Additionally, the fluoride injection system is in need of replacement or decommissioning due to
equipment age and concentration targets. Replacing equipment and controls will cost the city
several hundred thousand dollars.
Based on the 2018 Water System Plan, changes in infrastructure and operations, and the naturally
occurring fluoride levels in the water supply, replacing the fluoride injection system is not an
advisable use of city funds. The priorities outlined in the system plan for capital improvements,
especially the need to provide backup power generation to wells, the need to address recent PFAS
contamination, and the need to increase water production capacity are essential to maintaining
water service to our community. Additionally, the expanding list of primary contaminates from the
Washington State Department of Health includes minerals such as manganese and iron. These
minerals may require expensive filtration systems to be added to each of our wells. In the future,
when clean water is provided to all citizens and if the naturally occurring fluoride levels drop, the city
could consider replacing fluoridation equipment.
Ultimately, this decision reflects the City’s responsibility to carefully prioritize limited resources and
address the most pressing needs of our water system. At this time, the City must focus its
investments on ensuring reliable water production, maintaining critical infrastructure, addressing
PFAS contamination, providing adequate backup power, and meeting current and future regulatory
requirements.
Original article online at: https://www.cityofcheney.org/m/newsflash/home/detail/523