NorthWestern Corporation d/b/a NorthWestern Energy proposes to build and operate a 500 kV electric transmission line between southwestern Montana and southeastern Idaho. The Mountain States Transmission Intertie (MSTI) would meet customer demand for additional transmission capacity and relieve constraints on the existing high-voltage transmission system in the region.
"This is one of the first major transmission projects that we've undertaken since the mid-1980s and underscores our commitment to Montana and the region," said Mike Hanson, president. "This $800 million dollar investment is an appropriate and exciting growth opportunity for NorthWestern. We have spent several years evaluating this opportunity and it's time to move forward with development so that we provide a path for future regional energy development to follow."
"The demand for electricity in the western United States along with both the shift and increase in population centers has out-grown the current transmission lines that were built in the 1980's," said Dave Gates, vice president -- Wholesale Operations. "Through an Open Season process potential new generators expressed interest in expansion of the existing transmission path from southwestern Montana to Idaho. Investment in new transmission is needed to ensure a reliable transmission grid and to meet the delivery requirements of new generation facilities, including proposed clean coal technology and renewable energy facilities in Montana and Idaho. This investment would also upgrade existing facilities and provide capacity for the building of new generation projects."
The National Energy Policy Act enacted by Congress in 2005 took important steps to strengthen the nation's electric power grid. Congress also authorized mandatory reliability and interconnection standards, and directed the Department of Energy (DOE) to conduct a nationwide study of electric transmission congestion of currents systems, which was completed in August 2006. One of the areas of congestion that was identified in the study was the Montana, Idaho and Northwest Region.
The proposed MSTI project would extend approximately 350-390 miles from a new substation to be built either near Townsend or Garrison, MT to the existing Borah or Midpoint substations located in southern Idaho. The support structures would be constructed of lattice steel or tubular steel self-supporting towers with an average height between 110-130 feet. The span between towers would average 1500 feet, with a right-of-way width of approximately 220 feet. The company has not selected a preferred route although several reasonable alternatives have been identified. A final decision on construction will be made after the required permitting is completed. Under the current plan, the line would be placed into service in 2013.
"We are preparing an application for a certificate under the Montana Major Facility Siting Act (MFSA), and we will then proceed with environmental review under the National Environmental Policy Act (NEPA) and the Montana Environmental Policy (MEPA)," said Rick Walsh, manager -- Environmental Permitting. "The Montana Department of Environmental Quality (DEQ) will oversee the MFSA application, and will be the State lead agency for the subsequent Environmental Impact Statement (EIS)."
The Bureau of Land Management and USDA Forest Service will be involved in the Federal/State EIS jointly prepared with the DEQ. Consultations and coordination with other Federal and State environmental and permitting agencies will be required to meet other regulations.
Since there is no state siting law in Idaho, the federal environmental review process used in Montana will guide the public and agency review in Idaho. Construction cannot commence until all local, state and federal permits and regulatory requirements are met.
"This project, as proposed, would have a significant economic impact to the communities along the final route," said Gates. "Projects of this magnitude increase the local tax base, provide job opportunities and enable the development of more competitive energy sources in Montana, Idaho and the rest of the region."
NorthWestern Energy will conduct open house and communication programs for members of the public, various federal, state and local governmental agencies, local property owners and other interested parties