A giant drill bit has arrived in Indianapolis to bore an 8-mile-long tunnel designed to prevent raw sewage overflows into rivers and streams.
The 20-foot diameter hardened steel borer arrived last week from Mount Pleasant, Pa., and was shown off Tuesday by Citizens Energy Group. Once the rest of the machine arrives next month, crews will assemble it into a 450-foot-long boring machine that will cut the tunnel through bedrock underneath Indianapolis.
Boring work should begin in early January on the tunnel that's designed to hold more than 50 million gallons of sewage until it can be treated.
That tunnel is the first of several that by 2025 should stretch 25 miles and hold up to 250 million gallons of sewage to prevent overflows into rivers and streams.
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