A hacker recently attempted to add a “dangerous” level of chemicals to the water treatment plant in Oldsmar, Florida, according to the Pinellas County Sheriff’s Department.
While speaking at a press conference on Monday, Pinellas County Sheriff Bob Gualtieri said that the incident occurred on Friday when a plant operator at the Oldsmar Water Treatment Facility “noticed that someone remotely accessed the computer system that he was monitoring,” which controls the chemicals at the plant.
The employee didn’t think much of the system being accessed remotely, as supervisors and others have done so on several different occasions, Gualtieri said.
A few hours later at around 1:30 p.m. local time, the employee again noticed that his computer was being accessed remotely.
“The person remotely accessed the system for about three to five minutes, opening various functions on the screen,” Gualtieri said. “One of the functions opened by the person hacking into the system was one that controls the amount of sodium hydroxide in the water. The hacker changed the sodium hydroxide from about 100 parts per million to 11,100 parts per million. This is obviously a significant and potentially dangerous increase.”
Gualtieri went on to note that sodium hydroxide, “also known as lye” is used to control levels of acidity in the water as well as removing metals from it but added that it is also one of the main ingredients in liquid drain cleaner.
The change made by the hacker was noticed by the employee shortly after, and the employee was able to lower the levels of the chemical and Gualtieri said that “at no time was there a significant adverse effect on the water being treated.”
According to Gualtieri, the employee who noticed the breach notified his supervisor shortly after and took the necessary steps to prevent remote access again.
Gualtieri also noted that the hack brought the water treatment plant to “dangerous levels” of sodium hydroxide “but luckily it was caught right away.”
Newsweek was directed to the press conference after reaching out to the Pinellas County Sheriff’s Office for comment.
Oldsmar Mayor Eric Seidel and City Manager Al Braithwaite also spoke during the press conference on Monday and confirmed that the hack was made on the city’s drinking water supply.
While speaking on Friday, Seidel explained that the water treatment plant has several monitoring protocols to detect a change like the one on Friday.
“The protocols that we have in place, the monitoring protocols, they work; that’s the good news,” Seidel said. “Even had they not caught them, there’s redundancies that have alarms in the system that would have caught the change in the pH level anyhow.”
“The important thing is to put everyone on notice and I think that’s really the purpose of today is to make sure that everyone realizes that these bad actors are out there,” Seidel added.
Newsweek reached out to Seidel and Braithwaite for comment but did not receive a response in time for publication.