LOUISVILLE, Ky. (WDRB) -- A crane recently lifted a 125,000-pound piece of machinery from a shaft north of Cherokee Park as sewer district officials dismantle the mechanical mole that recently completed a 4-mile tunnel.

Nicknamed “Bumblebee” to honor Louisville boxing great Muhammad Ali and his “float like a butterfly, sting like a bee” slogan, the boring machine recently descended 200 feet underground to cut the path of the Metropolitan Sewer District’s Waterway Protection Tunnel. During heavy rains, the 20-foot diameter tunnel will hold overflows from the sewer system to prevent untreated water from passing into the Ohio River and Beargrass Creek.

A crane on Oct. 9 lifted a cutterhead, the tip of the 412-foot-long machine. The cutterhead alone weighs as much as 37 Ford Escapes.

Bumblebee’s 22-foot diameter circle has 38 cutters that apply nearly 1.5 million pounds of grinding torque against the bedrock.

The size of the machine requires that it be retrieved in pieces, a process that will take weeks. The pieces will be hauled away on trucks to be reconditioned and prepared for its next mission.

MSD said in a news release that the $200 million tunnel will be lined with a foot of concrete before it is expected to be put into service in the second half of next year. It will hold up to 55 million gallons of water, or as much as 83 Olympic size swimming pools.

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