Major water utilities in Wisconsin say they haven’t been affected by cyberattacks that have targeted water systems in neighboring states, including Michigan and Minnesota.
Representatives of water utilities in Milwaukee, Madison and Green Bay say their drinking water remains safe after systems in surrounding states experienced attacks on automated operations, including cyberattacks on more than 30 water systems in Minnesota.
Thencies have warned that Iranian hackers have caused technological disruptions of water and wastewater systems this year
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Pat Pauly, superintendent of Milwaukee Water Works, said its drinking water remains safe for the more than 950,000 customers they serve in Milwaukee, Ozaukee and Waukesha counties.
“There should be no concerns that we’ve been compromised in any way,” Pauly said. “But we do take these cyber attacks seriously, even though we’re confident that we’re not vulnerable to this particular form.”
The attacks are targeting Rockwell Automation programmable logic controllers, or industrial computers used to automate equipment. Hackers remotely accessed devices connected to the internet and changed IP addresses and passwords, resulting in the loss of control of some systems. Pauly said none of the utility’s PLCs are directly connected to the internet.
Milwaukee Water Works previously underwent a rigorous evaluation of its system in the lead up to hosting the Democratic National Convention in 2020 and Republican National Convention in 2024. At that time, Pauly said officials received recommendations to ensure its operational technology was isolated from the internet to prevent a cyberattack.
Marcus Pearson, public information officer for the Madison Water Utility, likewise assured that the drinking water provided to more than 250,000 people in the Madison area remains safe.
“We have not been affected in any way, shape, or form by these cyberattacks, but we are aware of them. We take every precaution to make sure that doesn’t happen to us,” said Pearson.
He noted the utility’s servers are located at multiple sites. Operators are monitoring systems around the clock. Pauly said the same is true for Milwaukee Water Works, saying it would know immediately if any attacks occurred.
Andrea Hay, communications director for the Green Bay Water Utility, said in a statement that the utility also maintains multiple layers of oversight, safeguards and continuous monitoring. The utility serves more than 200,000 total customers.
“Green Bay Water Utility has not experienced a cybersecurity incident affecting the safety or delivery of our drinking water in connection with the activity being reported nationally,” Hay said. “Our treatment and operational environment is structured differently from the systems described in those incidents and is not configured in a way that would allow the same method of access to manipulate our treatment process.”
In a July 28 memo, the Wisconsin Department of Natural Resources warned water and wastewater systems about possible threats from “malicious cyber actors” after the attacks in Minnesota. The memo states staff at the Wisconsin Statewide Intelligence Center expressed concern that programmable logic controllers at Wisconsin systems may be susceptible to attacks.
“This leads us to believe that the cyber threat is ongoing in Wisconsin and requires immediate action to prevent potentially serious impacts to our systems,” the memo states.
A DNR spokesperson said it’s coordinating with the center, which hadn’t confirmed any attacks as of Tuesday.
Since then, the Federal Bureau of Investigation and Environmental Protection Agency have issued a public service announcement warning that cyberattacks have affected water and wastewater utilities in at least seven states. The FBI has received reports of flooding and pressure loss in water systems, which could allow untreated groundwater to seep into pipes.
The DNR warned water and wastewater systems that a full system shutdown could result if a cyberattack were to cause pressure to drop significantly.
“Furthermore, for drinking water systems, it could create a suction effect that potentially allows unsafe contaminants to enter the system,” the memo states.
The federal Cybersecurity and Infrastructure Security Agency has also alerted water and wastewater systems that unauthorized activity has caused “boil water notices and sustained manual operations.”
An FBI spokesperson said it had no additional information to provide when asked about whether attacks have affected more states, including Wisconsin.
The FBI and EPA have recommended setting up secure firewalls and gateways, strong passwords and strict network controls to safeguard against attacks.
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