After 'Freak Accident' Pumps Too Much Chlorine In A Utah Pool, We Asked The Question Why Chlorine?

Jun 7, 2019

On Wednesday, due to a pump malfunctioned, too much chlorine was pumped into a public pool in Pleasant Grove, Utah causing dozens to be rushed to the hospital. 

With public pools opening up for the summer, it is important to know what nasty substances can end up in the pool and what chlorine actually does to keep us safe, if at the right concentrations.

“It's like bleach, you put bleach in your laundry to clean your clothes, make sure they smell right, don’t have bacteria, don’t have dirt,” said Rich Monk, who has been the pool manager at the Garden City, Utah public pool for seven years.

“Well, the chlorine in the pool does virtually the same thing—this free chlorine interacts with bacteria, other microbes, dirt and sweat. And the free chlorine becomes hypochlorous acid. So, if you go into a pool, and smell something that smells like chlorine, what you are smelling is actually this hypochlorous acid.”

He said the ideal concentration of chlorine in their heated indoor pool is 2-4 parts per million- that means for every 1 million water molecules, 2-4 chlorine molecules are present.

While the right amount of chlorine eliminates harmful substances and keeps the pool safe, too much can be harmful. Earlier this week, the chlorine pump at the Pleasant Grove Veteran Memorial Pool malfunctioned and released too much chlorine into the pool. About 26 people were sent to the nearby hospital after symptoms of coughing, vomiting and bleeding from the nose.

Most public pools have an automatic sensor that detects when chlorine needs to be added and when the hypochlorous acid needs to be filtered out. Monk emphasized how important it is to shower and not use the pool as a bathroom.

“The best thing we tell people to do is to take a shower before they ever get in the water and that helps a great deal," he said. "I mean, we do keep the pool water clean and that 2-4 ppm does keep the water safe, but urine in the pool doesn’t go away. There’s no way to filter that out."