Data points to water system in Grand Rapids being the source of Legionnaires’ outbreak

The state has released an update about the Legionnaires’ outbreak in Grand Rapids.

On Monday, the Department of Health said they’ve identified the source, and that data points to areas of the city’s water system.

Fourteen cases of Legionnaires’ disease have been confirmed since April 2023. 11 people needed hospitalization, but no one died.

According to the state, Legionnaires’ disease is a serious type of pneumonia (lung infection) caused by inhaling Legionella bacteria found in water.

Likely case exposures have been geographically clustered in homes and other buildings in the area north of Golf Course Road/SE 10th Street, south of NE/NW 8th Street, east of 11th Avenue SW/10th Avenue NW, and west of 7th Avenue SE/8th Avenue NE.

“We are working in partnership with the local water utility to determine the best way to address the situation,” said Tom Hogan, director of MDH’s Environmental Health Division. “Additional water sampling is planned, and the results will be analyzed and used to inform additional actions and communication.”

Legionella is commonly found in natural and manmade aquatic environments and can be found at low concentrations in any public water system. Legionella can live and grow in pipes and devices that use water. It lives and grows particularly well in water that is stagnant (not flowing), between 70°F and 120°F, or when it is not treated with adequate water treatment chemicals, such as chlorine.

The Grand Rapids Public Utilities water supply is one of the few community water systems in Minnesota that does not chlorinate its water. This is because some systems that draw water from groundwater sources, such as community wells, are not required to add disinfectants.

“Our immediate focus is developing the provisional plan to flush and disinfect areas of our water system, aiming to reduce the risk of Legionella. Installing a chlorination system is being looked into, but introducing chlorination to a previously unchlorinated system is a complex process, so our approach needs to be methodical to ensure we avoid any additional health, safety or distribution system complications,” said Julie Kennedy, Grand Rapids Public Utilities general manager. “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.”