TAMPA — A sinkhole recently opened under a wastewater treatment pond at Busch Gardens, dumping an estimated 2.5 million gallons of treated wastewater into the earth below, according to state environmental regulators and a theme park spokesperson.

Busch Gardens employees discovered the 15-foot-by-15-foot sinkhole in the early morning hours Nov. 18. The sinkhole opened in the last of a train of three ponds used in the park’s on-site wastewater treatment process, according to Brian Humphreys, a spokesperson for the Florida Department of Environmental Protection.

After finding the sinkhole, Busch Gardens closed a low dam connecting the second and third treatment pond, but not before enough wastewater to fill nearly four Olympic swimming pools dumped to the ground below. That dam between ponds remained closed as of Friday, Humphreys said.

The wastewater pond with the sinkhole is located a few hundred feet northwest of the popular water ride Congo River Rapids, according to coordinates of the spill provided by the park.

“The opening drained the pond of water underground. Water levels are monitored 24×7 and we were alerted to the issue as water levels began to slowly drop in the morning (on Nov. 18),” Eddie Delgado, a theme park spokesperson, wrote in a statement to the Tampa Bay Times.

The park alerted Florida’s environmental department that day, Delgado said.

The pond above the sinkhole does not hold raw sewage, Humphreys said. When wastewater is cleaned, it can go through several clean-up processes to remove fecal matter. At Busch Gardens, the first of three ponds removes biological material, the second pond removes nutrients and the third pond stores water as it is cycled through an ultraviolet disinfectant filter.

The third pond in that process is the one with the sinkhole, according to Humphreys.

Water sampling is ongoing, and Busch Gardens contracted an engineering firm to develop a plan to address the sinkhole, Humphreys said. Florida’s environment department has staff at Busch Gardens, including a professional geologist, to monitor the park’s response.

The state is also reviewing Busch Gardens’ permits and reporting requirements to determine what, if any, violations occurred or if there is a need for enforcement. The environment department will also be reviewing any proposed plan to address the sinkhole “to ensure it is protective of the environment and public health and safety,” Humphreys said.

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