LOUISVILLE, Ky. (WDRB NEWS) -- One year ago a massive sinkhole opened up at the Louisville Zoo, and now there's a legal fight over who's to blame.

The sinkhole opened up on March 6, 2019 in an area of the zoo that is partially above Louisville Underground. The owner of the Mega Caverns and Louisville Underground, Jim Lowry, is now suing the zoo.

Lowry said an incorrectly placed water drainage system caused more than 100 million of gallons of water to flow over the area where the ground caved in. According to the lawsuit that's enough water to fill nearly 4,000 full sized Olympic swimming pools. The suit claims several engineers agree the water flow caused the sinkhole. 

"Engineering reports have confirmed that the (sinkhole) was caused by two decades of directed water flow from an improperly placed water drainage system constructed in the late 90’s or early 2000’s,” Lowry told WDRB News in a statement.

“This directed water flow into the affected area of the mine expedited the degradation of the joints in two decades that would have naturally occurred over the course of thousands of years,” he said.

The same day the suit was filed, the Jefferson County attorney sent to Lowry a demand letter that blames the sinkhole on mining and alleges that Mega Caverns says Mega Cavern "is strictly liable for injuries to the Zoo."

The zoo is a nonprofit, but also an agency of Metro Louisville government.

Metro Government said the sinkhole cost the city more than $2 million, including $441,000 in lost revenue to the zoo last year because it could not operate its train and because it had to close for 10 days. In addition, the government said, it estimates the cost to relocate the train track a safe distance from the sinkhole at $1 million.

Metro government also said that it would be in the best interest of both parties to work together” to immediately identify and eliminate any areas of the mine at risk.”

And, the government warned, if no such cooperation is forthcoming, it would resort to litigation.

Lowry, meanwhile, said that he did not make the decision to file suit lightly.

"We feel that we’ve exhausted all of our options to fix an issue that is beyond our control," he said. "We are simply requesting that those responsible rectify the permanent damage that has been caused to our facility."

Zoo officials said in a statement that staff and engineers continue to take steps to ensure safety in the affected area.

"The Louisville Zoo has communicated with Mega Caverns our desire to find a cooperative resolution that ensures full and safe enjoyment of both our respective attractions," the zoo said.

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