FBI probes water system cyberattacks hitting Michigan, Minnesota

Cyberattacks targeted more than 30 water systems in Minnesota and at least nine in Michigan, state officials said on August 1, 2026, as the FBI investigates the security breaches.

Dale George, communications director for Michigan’s Department of Environment, Great Lakes, and Energy, said the nine systems showed activity consistent with a federal alert issued on July 28, but all operated safely and no public health concerns arose.

Minnesota IT Services reported on July 30 that no communities had requested residents alter drinking water usage. The agency said most confirmed attacks involved remote monitoring and control technology, and that malicious activity did not always disrupt water service.

In Braham, a city of about 1,700 people roughly 70 miles north of Minneapolis, a cyberattack on July 27 shut down well and treatment plant controls. Residents were asked to minimize water use for several hours while the city relied on its water tower. No water quality problems were reported.

In Plymouth, a city of about 80,000 outside Minneapolis, water infrastructure communications were restored by the afternoon of July 28 after a cyberattack.

The FBI, the Cybersecurity and Infrastructure Security Agency and other agencies issued an advisory on July 21 warning that Iranian hackers have been targeting water and wastewater systems. An FBI statement on August 1 said it is fully engaged with partners to protect critical infrastructure but did not identify a culprit in the current attacks.

Water utilities often lack funding and expertise for robust cybersecurity, making them attractive for attackers seeking disruption and public panic. Iran’s interest in U.S. water systems dates back years; Iranian hackers were charged in 2016 for a cyberattack on a dam near New York City.

During a Cabinet meeting on July 31, Donald Trump claimed without evidence that the Minnesota attacks were the state’s fault. Governor Tim Walz responded that Trump knows who is responsible and that other states were hit as well.