City Utilities Director Kumar Menon said he was pleased with the bids and said the number of interested firms helped keep costs down. Similar projects in other cities have not been so fortunate, he said. City officials will spend the next several weeks analyzing the bids before awarding a contract.
But as The News-Sentinel reported last month, all of the bidding firms should be qualified to do the job because the city required interested firms to prove their qualifications in advance of being allowed to seek the contract.
The tunnel will begin at the city's Water Pollution Control plant and extend five miles 200 feet below the surface before terminating near Foster Park. By channeling materials currently handled by combined storm and sanitary sewers directly to the plant, the tunnel will prevent most so-called "combined sewer overflows" (CSOs) that occur during heavy rains. The federal government has required the city to reduce its CSOs.
Some bids for the project were awarded in 2014, including about $15 million in preliminary engineering contracts. Coming later will be bids for the machinery needed to lift the sewage from the tunnel into the treatment plant and for two larger vertical shafts: one near the Water Pollution Control plant on Dwenger Avenue that will allow machinery and workers into the tunnel and another near Foster Park that will be used to remove the equipment. Once the tunnel is complete, the entrance and exit shafts will be closed but will be accessible for maintenance needs. Machines used to bore the tunnel through bedrock can cost millions of dollars and must be assembled in the tunnel, Menon said.
The tunnel will be 16 feet in diameter, lined with concrete and able to handle 800 million gallons per day. The digging process itself will displace about 450,000 cubic yards of stone — enough to fill a football field 136 yards high. That's just a few feet shorter than Fort Wayne's tallest building, the I&M Power Center.