NOVI, Mich., Sept. 30, 2013 – ITCTransmission, a wholly-owned subsidiary of ITC Holdings Corp., the nation’s largest independent electricity transmission company, today announced that Phase 1 of its 140-mile Thumb Loop high-voltage transmission line has been placed into service. Phase 1 consists of 62 miles of double-circuit, 345,000 volt (345 kV) lines from the new Bauer substation in Tuscola County to the new Rapson substation in Huron County.

“Putting Phase 1 of the Thumb Loop project into service on time and on budget is a testament to ITC’s independent transmission model,” said Gregory Ioanidis, president of ITC Michigan. “This project will strengthen the transmission grid in the Thumb area of Michigan and also will serve as a backbone for the interconnection of new generation sources in the area. It will increase transmission system capacity and reliability, enable the delivery of lower cost generation and provide more efficient transmission of energy.”

During the construction phase, ITC estimates that the entire Thumb Loop project will have a direct impact of $366 million to the Michigan economy, including jobs with local contractors, vendors and suppliers. The area economy benefits from the demand for supplies and services such as concrete, hardware, fuel, gravel and trucking, as well as food, lodging and other personal needs for construction crews.

Work is proceeding on schedule for the remaining segments of the Thumb Loop project. All poles have been erected and the conductors are being installed along the 20-mile Phase 2 section in St. Clair County. Construction on Phase 3 from the Rapson substation in Huron County through Sanilac County to the Greenwood substation in St. Clair County will get underway in the first quarter of 2014. The entire project will be completed and in service in 2015.

Thumb Loop by the Numbers (project totals)
Miles of wire: 3,640
Number of steel monopoles: 786
Number of steel lattice towers: 30
Distance between poles: 800 – 1,100 feet
Average number of poles per mile: 6
Height of poles: 130 – 180 feet

Note to editors: High-resolution photos and video of the Thumb Loop project are available. Please contact Joe Kirik at 248.946-3478 or

About the Thumb Loop Project
The Thumb Loop project consists of approximately 140 miles of double-circuit 345,000 volt (345 kV) transmission lines and four new substations. It will serve as the “backbone” of a system designed to meet the identified maximum wind energy potential of the Thumb region and will be capable of supporting a maximum capacity of about 5,000 MW. As an important link in the high-voltage transmission system in Michigan and the region, it also will contribute to reducing congestion, improving system reliability and facilitating wholesale market competition. Additional lines and facilities will be needed in the future as wind generators go into service and connect to the backbone system. The project is being constructed in stages. Construction on the first segment, the western side of the loop from Tuscola County to Huron County, began in the second quarter of 2012 and was completed in September 2013. The remainder is targeted for completion by 2015. For more information about the Thumb Loop project, please visit