MDH identifies Grand Rapids water system in Legionnaires' outbreak
Grand Rapids is addressing the Legionnaires' outbreak with the Department of Health collaboration and considering a potential chlorination system installation.
GRAND RAPIDS — The Minnesota Department of Health identified areas of the Grand Rapids municipal water system as the source of the city’s Legionnaires’ disease outbreak.
A total of 14 cases of the lung infection were identified since April 2023, according to a news release from the health department. Grand Rapids Public Utilities General Manager Julie Kennedy said GRPU is considering installing a chlorination system to reduce the risk of infection.
“We will be providing local updates and customer notices as that plan develops along with continuing to work with MDH and a team of experts to conduct a thorough assessment of our water distribution system to determine the best long-term solution,” Kennedy stated in the release.
Legionnaires’ disease is contracted by breathing in water vapor that contains the Legionella bacteria. It cannot spread from person to person nor by drinking water containing the bacteria.
“There is no risk at this point of any kind of emergency for drinking water,” Kennedy said in a GRPU update video in January.
The state health department began investigating the outbreak after the first cases of the disease were reported. Likely exposures were clustered in a 2-square-mile area in central Grand Rapids. Two building samples tested positive for the bacteria, though none was found in the water treatment plant or the distribution system, according to the update video.
Legionella is a naturally occurring bacteria found in any public water system in low concentrations. It can live and grow in any pipes or devices that use water, though it thrives in stagnant water between 70 and 120 degrees or when not treated with chemicals like chlorine.
Grand Rapids has one of the few public water systems in Minnesota without a chlorination system. Brainerd is another, home to the largest unchlorinated system in the state. Although a water boil order over the summer there and other concerns about copper in the system have that city exploring permanent chlorination as well.
Of the 14 cases in Grand Rapids, 11 were adults and 11 required hospitalization. There have been no deaths associated with the outbreak. On average, 1 out of every 10 people infected with Legionnaires’ disease dies. In 2023, Minnesota had 134 cases and six deaths.
MDH said building owners should follow best practices for maintaining healthy building water systems. Residents can mitigate the risk of waterborne diseases like Legionnaires’ by regularly cleaning devices that use water and using distilled water in humidifiers and medical devices like CPAP machines.