The chemical issue was reported on the indoor water park's grand opening day Wednesday.
HOUSTON, Texas (KTRK) -- Authorities say more than a dozen construction workers were hospitalized Wednesday morning following an improper mix of pool chemicals at the Great Wolf Lodge Water Park in Webster.
The Webster Police Department confirmed the chemical incident along Great Wolf Way on the indoor water park's grand opening day.
Webster Fire Chief Dean Spencer said crews responded to a call about breathing problems caused by a chemical reaction in the pool house, which is separate from the hotel and water park.
The chief said first responders learned a contractor had mixed two "unlike" chemicals - sodium hypochlorite and sulfuric acid - resulting in the chemical reaction.
SkyEye flew over the active scene, where multiple ambulances could be seen assisting. The fire chief said 16 employees and contractors working in the immediate area were transported to the hospital, some out of precaution. The City of Webster officials added that five individuals had evacuated the building.
"At this time, there is no issue with the chemicals. They have all been resolved," Spencer said. "At no time was the hotel or waterpark affected by this event."
After Great Wolf Resort's initial response of having to wait until their opening ceremony celebration to release any information, they sent the following statement:
"The health and safety of our guests and pack members is always our priority, and we greatly appreciate the quick actions of first responders from the city of Webster in response to an incident at an external building outside of the main indoor water park and resort caused by an external vendor. We've received the all-clear to open the resort and all water park attractions as planned this afternoon from the Webster Fire Department."
The resort features 532 guest suites, a 92,000-square-foot indoor water park, a 61,000-square-foot adventure park, and nearly 15 dining and retail outlets.
Spencer said construction workers were finishing work on the property, where Hawkins was the contractor.
According to the fire chief, two facilities run the pool. The incident reportedly happened at an outside pool house that runs the outside pool.
Spencer said it was unclear why the chemicals were improperly mixed and added that an investigation would be conducted to determine why it occurred.
"The situation was quickly contained and will not affect the Lodge's operations (Wednesday). An environmental company is working with Great Wolf Lodge and the contractor to clean the tanks safely," Webster city officials said in a release.
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