The City of Fargo has been notified by the North Dakota Department of Health that a routine monthly drinking water sample collected on December 11, 2017 at its Fargo Water Treatment Plant (FWTP) was not in conformance with the Environmental Protection Agency (EPA)’s standard average of 0.010 milligrams per liter for bromate concentration. The sample concentration in December 2017 at the FWTP was 0.088 milligrams per liter. Bromate forms when ozone, used to disinfect drinking water, reacts with naturally-occurring bromide found in source water.
In a review of data from the water samples, there was a nine-day period, December 7-15, in which bromate concentrations may have been at levels to increase the standard average calculation above the EPA standard. During this time, Sheyenne River water was being used in the plant and a mechanical failure with monitoring equipment in the ozone process resulted in incorrectly low ozone readings. Bromide concentrations are typically higher in the Sheyenne River than the Red River.
The City took immediate steps to correct this issue with ozone process monitoring, including frequent inspection of sample flows to ozone monitoring equipment and daily sampling for bromate at two plant locations. The usage of Sheyenne River water ceased on December 15 and the bromate concentrations, correspondingly, reduced dramatically. The Red River is the only source of water being used at the plant at this time, and recent samples analyzed at the FWTP show bromate levels around 0.001 milligrams per liter (or about 10% of the EPA standard maximum).
The Sheyenne River will be used sparingly as a raw water source until new technology in the FWTP is operational in mid-2018. One of the primary objectives for expanding the FWTP was being able to fully comply with bromate regulations; the existing plant would unlikely be able to meet the EPA standards if long-term usage and treatment of Sheyenne River water were required. The FWTP expansion includes the implementation of additional computer control features to provide improved diagnostic information for the ozone infusion process. There have been no previous compliance issues at the FWTP for bromate since the EPA standard was implemented in 2002.
This issue is not cause for alarm and there is no need to use an alternative water supply (i.e. bottled). Dr. John Baird, Health Officer for Fargo Cass Public Health, stated “A limit is set for the level of bromate in drinking water because of a concern that some people exposed to high levels over many years may have an increased risk of cancer. I see no health risk to our community from the short time that bromate levels were over the established limit.”
In addition to this public notice, website notices and social media updates, the City is directly mailing postcards to its drinking water consumers in Fargo, West Fargo and the Cass County Rural Water District. Postcards are being printed and will arrive in residents’ mailboxes next week.
Troy Hall, Utility Director for the City of Fargo, stated “Fargo is strongly committed to continuing to provide high quality drinking water to the metro’s residents, while implementing even more robust monitoring and safeguards in response to this issue. If residents have additional questions, they are encouraged to contact the City of Fargo’s Water Treatment Plant at 701.241.1469.”