After Legionnaires' outbreak in Hopkins, an effort to regulate cooling towers

It took weeks for the Minnesota Department of Health to find the source of a Legionnaires' disease outbreak in Hopkins that killed one person and sickened 23 others last year.

Now a state representative for the west metro suburb wants to make sure it never takes that long again to figure out where an outbreak began.

State Rep. Cheryl Youakim, DFL-Hopkins, introduced a bill earlier this month that would create a state registry of cooling towers, often the source of widespread cases of the respiratory disease.

Cooling towers extract heat through the evaporation of water and release water vapor and droplets into the atmosphere. But they can produce aerosolized water particles contaminated with Legionella bacteria, which can make people sick if inhaled.

A registry, Youakim said, "would prevent more people from getting sick in an outbreak because you'd be able to find [the source] more quickly."

Youakim said she has received pushback from building owners who don't want to be fined for failing to register and from cooling tower manufacturers who think a registry would lead to more regulations.

"I'm starting very simple," she said. "It may eventually be the way we need to go."

The bill would require owners of buildings with cooling towers to register the tower with the state health commissioner. Owners could be fined up to $1,500 if they failed to do so, according to the bill's language, and would need to follow inspection and cleaning guidelines for cooling towers outlined by the Centers for Disease Control and Prevention.

The Alliance to Prevent Legionnaires' Disease, a nonprofit coalition supported by cooling tower manufacturers, said registering towers won't prevent future outbreaks.

"The focus ... on building equipment is misplaced," said Daryn Cline, who works for the Alliance and cooling tower manufacturer Evapco. "More must be done to better monitor and disinfect against Legionella in the public drinking water system."

But Dr. Janet E. Stout, president of the Pittsburgh-based Special Pathogens Laboratory, said the bill would make investigations more efficient. "This is about education and making sure people know the proper way to operate cooling towers," she said.

After September's outbreak, Health Department investigators determined within days that the cause was a cooling tower. But they had to search for it using satellite maps because there was no registry. It wasn't until they received a tip that they were directed to a tower at the Citrus Systems plant in Hopkins.

"Within two days they had figured out that the source was a cooling tower. It took them up to three weeks to find that cooling tower," Youakim said.

More than 110 people contracted Legionnaires' disease in Minnesota last year, a sharp increase from the 50 to 58 who came down with it annually from 2012 to 2015. Most people exposed to the bacteria are not infected, but smokers or people with a weakened immune system are at an increased risk.