Wellington Free Ambulance has confirmed 15 people, all under the age of 18, are being treated following a chemical spill at H20 Extreme in Upper Hutt.
Ten of those patients are in a moderate condition and have been transported to Hutt Valley hospital.
The other five patients are in a minor condition.
Fire and Emergency New Zealand told 1 NEWS they arrived on scene at 1.40pm and then evacuated the pool.
Emergency responders are currently on scene working with Worksafe.
“We are checking the chlorine levels at the moment to check that it is safe,” a Fire and Emergency spokesperson said.