Michels completes Blacklick tunnel12 October 2018
Ohio – Michels announced October 9 it has reached the successful completion of the final drive on the 4.5-mile (7km) Blacklick Creek Interceptor Sanitary Sewer in Columbus, three months ahead of schedule.
Up to 75 crew members have been working in Blacklick, Ohio, using a 12ft (3.6m) diameter EPBM to install the 10ft inner diameter, fiber-reinforced precast concrete final liner, according to the contractor. The machine and tunnel passed through two intermediary shafts and negotiated 12 curves covering approximately 70 per cent of the alignment.
A particular challenge of this project was the high variability of ground conditions, Michels said. Although EPBMs are typically suitable for soft ground, the Blacklick machine was specially designed to handle shale rock as well.
Completion of the drive is a significant milestone on the project. Next, crews will spend several months building concrete structures in shafts and completing surface restoration.