LOUISVILLE, Ky. (WDRB) -- There's a massive hole in the parking lot at Churchill Downs, and it stretches for 33 acres. And the hole will help save the environment, and save people money, MSD Engineer Jordan Basham said.

The parking lot construction project will install a giant basin under the pavement to catch rainwater and stop it from getting into the sewer system. It will allow the water to drip slowly from the basin into the ground.

“It [won't] have a chance to enter the sewer system and cause it to overflow,” Basham said. “When an overflow occurs, it can put contaminated sewage water into our streams or into the Ohio River and degrade the water quality.”

The basin will help keep waterways clean, and if the rainwater stays out of the sewer system, MSD won’t have to treat it, which will ultimately save money.

“We expect it will save MSD rate-payers approximately $1 million over a 20-year period in treatment costs,” Basham said.

MSD is investing more than $4 million, and Churchill Downs will spend nearly $33 million on the project.

The first phase of the project covered 22 acres and finished just in time for the Kentucky Derby earlier this year. The second phase will cover 33 acres and will finish just in time for the Breeders' Cup, which is the first weekend in November.

When the project is finished, Churchill Downs General Manager Ryan Jordan said visitors will notice a difference in their parking experience.

“We had a large parking area that was very disjointed at times,” Jordan said. “We tried to unify that and improve the arrival experience for all guests coming to visit the track.”

The whole project should be finished by the middle of October.

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