The FBI is investigating cyberattacks that have impacted water systems in Michigan and Minnesota, though officials have stated that all affected systems continued to operate safely. The reports emerged following a federal cyber alert issued last week, warning of potential tampering with the operational technology of water and wastewater systems.
Michigan confirmed on Saturday that nine of its water systems experienced activity consistent with the federal alert. Dale George, director of communications at Michigan's Department of Environment, Great Lakes, and Energy, stated that local operators addressed the issues and there were no known impacts posing a public health concern.
Earlier in the week, authorities reported that over 30 water systems in Minnesota were targeted. The FBI, along with the Cybersecurity and Infrastructure Security Agency and other partners, warned that Iranian hackers have been focusing on these critical infrastructure sectors. The FBI has not publicly identified a culprit and declined to comment on who might be responsible.
"The FBI is aware of recent public reporting around Water and Wastewater (WWS) sectors," the agency said in a statement. "The FBI and our interagency partners are fully engaged to protect critical infrastructure and we remain well-equipped to protect against cyber threats of all varieties."
In Minnesota, most confirmed attacks involved the technology used for remote monitoring and control of equipment. The state agency confirmed malicious activity but noted that not every impacted community experienced a disruption to water service.
The city of Braham, Minnesota, experienced a temporary outage for its water plant on Monday, leading to a brief request for residents to minimize water use. The city stated the attackers shut down the operating controls for the well and treatment plant, leaving them reliant on water stored in their tower for a few hours. Water quality was not affected.
In Plymouth, Minnesota, officials reported on social media that their water infrastructure communications were restored by Tuesday afternoon after a cyberattack.
Digital warfare has increasingly targeted sectors like water treatment facilities and healthcare, which may lack the resources and expertise for the latest security measures. These sectors are considered vulnerable targets due to the potential for causing widespread panic.
Iran's interest in U.S. water systems is not new. In 2016, the Justice Department charged a group of Iranian hackers in connection with a cyberattack targeting a small dam near New York City.