The Milk River dam (Photo via the United States Bureau of Reclamation).
The City of Havre is asking vulnerable residents with severely compromised immune systems to continue to boil their water to stay safe from Giardia after the city saw a 56% increase in residents seeking care for diarrhea as compared to last year.
After more than a month, Havre reduced its boil water advisory last week to a health advisory, meaning only the elderly, infants and those with weak immune systems have to continue boiling water. Everyone else can go back to normally consuming water.
The City of Havre announced the boil water advisory on April 19 after three residents had confirmed cases of Giardia, which is a parasite that causes diarrhea. Since February, 95 people have self-reported similar symptoms.
The county health department said the city was aware of disinfection and filtration issues in February and March and the city water supply didn’t meet Safe Drinking Water Act standards.
Last week the city downgraded to a Health Advisory, meaning people without vulnerable immune systems no longer have to boil water and can drink as usual. The city public water supply is disinfecting drinking water and flushing the distribution system to reduce the likelihood of Giardia pathogens, the city said in a press release.
Havre’s Director of Public Works Trevor Mork said in an email Wednesday the water treatment plant has been working diligently to reduce risk and is well within compliance standards for at least two metrics, one being an increased level of chlorination, which reduces the likelihood of infection and pathogens.
Drinking contaminated water is how most people in Montana get a Giardia infection, with 58% of cases in 2023 stemming from exposure to recreational water or drinking untreated water, according to the Hill County Health Department.
The Milk River is the primary source of Havre’s drinking water, according to the Havre Water Department. A spokesperson for the Department of Environmental Quality, Nolan Lister, said Chinook and Harlem also source their water from the Milk River.
Lister said Havre’s surface water treatment plant, where water is treated to be safe for consumption, is operating under the requirements of the federal Safe Drinking Water Act.
State health department spokesperson Holly Matkin said waterborne outbreaks are generally rare in Montana. Matkin said a 2022 campylobacter outbreak, which also causes diarrhea, was the only other waterborne disease to hit Montana since 2019. Nineteen people got sick after drinking from the same contaminated outlet of surface water from a creek in Paradise, according to the Centers for Disease Control. The first cases were reported on May 9 and the last case was reported June 16 of 2022.
People can develop symptoms seven to 10 days after exposure, with other common avenues for infection being contaminated food or from other people.
From Jan. 1 to May 16 there were three confirmed positive cases of Giardia. The county health department concluded those people likely got it from the city’s public water supply, as they lived within city limits, consumed that water and had not been exposed to recreational water or water from other countries.
The county said the first disinfection failure was identified in the public water supply on February 2, 2024, and in the two weeks after there was a 100% increase in healthcare visits for diarrhea as compared to 2023.
Healthcare visits for diarrhea increased by 56% between late January and early May compared to the same period in 2023.
Once the boil water advisory was put in place, which kills Giardia in one minute, there was a decrease in people reporting symptoms.
The Hill County Public Health Department and the Montana Department of Public Health and Human Services from April 23 to May 16 conducted an online public health survey for Havre residents to report gastrointestinal illnesses and 227 residents completed the survey.
They provided information about their water consumption from various water sources, Gl illness symptoms, symptom onset date, length of illness, and other possible exposures. This survey is how the county learned of the 95 people who had Giardia symptoms who hadn’t officially tested positive.
On May 7 Department of Environmental Quality personnel assisted the city with taking samples for free chlorine residuals, as chlorine helps reduce the chances of Giardia spreading, a spokesperson for the department said.
The city requested to have the boil water advisory reduced on May 17, but was initially denied because the samples did not show enough chlorine, according to DEQ. But last week Havre officials were notified the city water treatment plant is being downgraded to a health advisory.
DEQ, the U.S. Environmental Protection Agency, and a private contractor were in Havre from May 20 to 24 to perform a Comprehensive Performance Evaluation, and a full report is expected to be completed in the next 60 days, Lister said.
The post Immunocompromised still need to boil drinking water in Havre appeared first on Daily Montanan.