With the completion of Bauer Substation in April 2012, M. J. Electric (MJE) began the next phase of the ITC Thumb Loop Project with the Bauer to Rapson Transmission Line. The Bauer to Rapson Line involved the installation of a new double circuit 345-kV transmission line from the Bauer Substation near Frankenmuth to the Rapson Substation near Bad Axe, Michigan. The entire project runs approximately 62 mi through both Tuscola and Huron Counties. Construction included the installation of 353 steel monopoles and 10 steel lattice towers on drilled pier foundations, and double circuit 2-bundled VR2 conductor and OPGW. Installation of the drilled pier foundations began in April 2012 and the project was completed September 2013.
Construction began Summer 2012 on the new Rapson 345-kV Substation, near Bad Axe, Michigan. The 345-kV yard consists of three 345/120-kV transformers, eleven 345-kV gas circuit breakers and twenty six 345-kV disconnect switches. Site work began in January 2013 and completed in September 2013.
Construction began in March 2013 on the second segment of transmission lines to complete the Thumb Loop Project. The transmission line projects Greenwood-Fitz and Belle River-Fitz involve the installation of new double circuit 345-kV transmission lines between Greenwood Substation and the future Fitz Substation and on the existing Belle River tap. The combined projects total approximately 17 mi in St. Claire County starting near Avoca and ending near Memphis, Michigan. Construction includes 100 steel monopoles, eight steel lattice towers including drilled foundations, and double circuit 2-bundled VR2 conductor. The shield wire is a combination of steel and OPGW. Installation of OPGW will be assisted by a helicopter for the Greenwood-Fitz project, while the steel shield wire on Belle River-Fitz will be installed by hand.
In addition to the new line, an existing 765-kV transmission line will be modified to create two more 345-kV lines from Fitz to Blackfoot. This line includes an additional monopole and eight additional steel lattice towers on drilled pier foundations. Construction began in March 2013 with scheduled completion in January 2014. The overall Thumb Loop Project is projected to finalize in the Spring 2014 with the completion of the Fitz Substation. The new Fitz substation is a 345-kV switching station located in Wales Township comprised of five rows of breaker-and-a-half configuration, including twelve 345-kV gas circuit breakers and twenty four 345-kV disconnect switches.
The third phase of the ITC Thumb Loop project will connect the first and second phases running from the Rapson Substation south to the Greenwood Substation. It will also connect to the proposed Banner Substation near Sandusky, MI. ITC is planning to have the Thump Loop in service at the end of 2015.