Enbridge Alberta Clipper & Southern Lights
Michels Directional Crossings installed 33 crossings in five months for the 36-in. Alberta Clipper and the 20-in. Southern Lights pipeline projects.
Work began near Leonard, Minn., and made its way to Superior, Wis. Michels installed 47,600 ft of 36-in. pipe, with installations varying from 1,300 to 5,200 ft for the Clipper.
The Southern Lights project was 30,837 ft of 20-in. pipe, with crossings ranging from 1,000 to 5,200 ft. Michels sent nine of its 14 large capacity drill rigs to work on the project at one time — the first time in Michels’ long history that it has resourced out so many for one contract within a 150-mile radius.
Temperatures ranged from the mid-80s to 20-below F, making the conditions extremely challenging. Additionally, while working on the project, Michels executed three HDD pullbacks in one day.
Project Owner: Enbridge
Engineer: J.D. Hair & Associates
Contractor: Michels Corp.
Microtunneling Under Lake Oahe in South Dakota
Michels Tunneling was contracted to bore a 950-ft tunnel underneath South Dakota’s Lake Oahe, a project that was supported with $18.9 million in economic stimulus funds. The water intake pipeline will provide drinking water to the Standing Rock Sioux tribe reservation. Michels used an Akkerman Inc. MTBM SL46 to install the 950 ft of 44-in., 16-ft length Permalok pipe. Among the challenges was that Michels anticipated a 60-ft high water table but instead encountered one that was 82 ft high, increasing the project’s difficulty.
Michels had to drill a 110-ft deep caisson with a diameter of 20 ft on the shore to launch the machine. Also, the underwater retrieval of the MTBM became much more difficult with the additional water table depth, forcing Michels to create new plans to retrieve the machine. Aided by A.D. I. Marine Professionals, Michels performed the wet retrieval of the MTBM. The retrieval process took two days, while the entire tunnel took six weeks.