Raw Water From a Roadside Spout Sickened 19 in Montana With Campylobacter

Drinking "raw water" — water that hasn't been disinfected or filtered — has become an emerging trend in the United States, and it can have serious consequences: untreated water from lakes, rivers and streams can carry germs that cause illness and outbreaks. In 2022, a western Montana community faced an outbreak of 19 cases of diarrheal illness tied to untreated surface water.

The outbreak

On May 9, 2022, Sanders County reported six active cases of Campylobacter infection to the state — a substantial increase over the county's 2017–2021 average of six reported cases a year. Every patient had drunk water from "watering point A," an outlet of creek water near Paradise, Montana.

The water source

• The outlet sits in a Montana Department of Transportation highway right-of-way on railroad property. It was probably built in the early 1900s to keep the creek from eroding the track bed.
• Neighboring landowners began using the water for household and farm needs, and the public came to use it for drinking water.
• Although it carries untreated surface water, many people believed it was a natural spring. They filled containers under the water spilling from its concrete box, dipped them into the box, or pumped water into large containers.
• Signs posted by the Department of Transportation before the outbreak warned that it was not an approved public water source.

Proving the link

Inside the box, investigators found an empty bird's nest. Birds are a known source of Campylobacter, so they may have been the main source of contamination, though none were present when the sample was taken.

Shutting it down

The combined epidemiologic, environmental and laboratory evidence was strong enough to take the outlet out of use.

• After a June 16 meeting, the Montana Department of Environmental Quality ruled that the outlet met the definition of a public water supply: it had to meet the Safe Drinking Water Act or be closed for good.
• On June 28, 2022, the Department of Transportation permanently removed public access, rerouting the creek water to stay underground.
• No new cases have been found since June 16.

If you drink water from outdoors

Always treat water from creeks, rivers and streams before drinking it. Boiling is the most reliable way to kill germs; treatment that includes filtration also lowers the risk.

Sources

Based on Hinnenkamp R, Sorenson S, Evanson E, Yoder J, Mattioli M, "Notes From the Field: Campylobacteriosis Outbreak Associated with Consumption of Raw Water — Montana, 2022," Morbidity and Mortality Weekly Report 72(15), CDC; a work of the United States government in the public domain.