Updated Feb 6, 2020 at 10am.

Following corrective actions and additional testing, the fluoride level in the City of Dubuque water system has returned to the desired level as of 9:30 p.m. on Wednesday, Feb. 5, 2020.  Testing indicated the fluoride level has returned to under 2.0 milligrams per liter (mg/l) and water customers can immediately return to regular water use.  This incident posed an extremely low risk due to the short duration of the elevated fluoride levels.

(original story)

IMPORTANT INFORMATION ABOUT YOUR DRINKING WATER
Temporarily Elevated Fluoride Levels Detected in Dubuque Drinking Water
Feb. 5, 2020

A fluoride concentration of 3.07 mg/l was detected in the drinking water provided the City of Dubuque Water Department this afternoon (Wednesday, Feb. 5, 2020).  This is a temporary condition and an update will be provided by 7 a.m. on Thursday, Feb. 6.

The City of Dubuque Water Department is taking active measures, including flushing the distribution system, to return fluoride levels to below 2.0 mg/L.  A public notice will be issued when levels have returned to standard operating levels below 2.0 mg/L.

At low levels, fluoride can help prevent cavities but children drinking water containing more than 2.0 milligrams per liter (mg/l) of fluoride over a prolonged period of time may develop cosmetic discoloration of their permanent teeth (dental fluorosis).  Dental fluorosis, in its moderate or severe forms, may result in a brown staining and/or pitting of the permanent teeth after prolonged exposure to elevated fluoride levels. This problem occurs only in developing teeth, before they erupt from the gums.

As a precaution, the City of Dubuque Water Department recommends children under nine be provided with alternative sources of drinking water OR water that has been treated to remove the fluoride to avoid the possibility of staining and pitting of their permanent teeth. You may also want to contact your dentist about proper use by young children of fluoride-containing products. Older children and adults may safely drink the water.

Drinking water containing more than 4.0 mg/l of fluoride (the U.S. Environmental Protection Agency’s drinking water standard) can increase your risk of developing bone disease. Your drinking water does not contain more than 4.0 mg/l of fluoride, but we’re required to notify you when we discover that the fluoride levels in your drinking water exceed 2.0 mg/l because of this cosmetic dental problem.

For more information, please call Denise Blakeley Ihrig, Water Department Manager, or Brant Schueller, Water Distribution Manager, with the City of Dubuque Water Department at 563.589.4291. Some home water treatment units are also available to remove fluoride from drinking water.  In Iowa, home water treatment units are regulated under 641—Chapter 14, with the water treatment unit registration program administered by the Iowa department of public health’s environmental health division. In addition, you may call the National Sanitation Foundation (NSF) International, at 1-877-867-3435.

This notification is required by the Iowa Department of Natural Resources.  Please share this information with all the other people who drink this water, especially those who may not have received this notice directly (for example, people in apartments, nursing homes, schools, and businesses). This notice is being sent to you by the City of Dubuque Water Department (Dubuque Water Works)

Fluoride Information
Community Water Fluoridation Information from the Iowa Department of Public Health
Community Water Fluoridation Information from the Centers for Disease Control and Prevention