Home Library PowerLine PowerLine - MSTI - Case Study

Attention: open in a new window. PDF | Print | E-mail

Mountain States Transmission Intertie (MSTI)

Project Description

In 2008, NorthWestern Energy proposed the Mountain States Transmission Intertie (MSTI), a 500kV AC line intended to bring, in part, wind energy from Montana's central plains to western markets. A preliminary draft environmental impact statement (EIS) for the line, issued by the Bureau of Land Management in 2010, was challenged in court by Jefferson County, Montana. Subsequently, Madison County, Montana sought an independent review of MSTI, to address the concerns raised by both counties regarding the project's environmental and community impacts.

The review—dubbed the MSTI Review Project (MRP)--is a collaborative project of the two counties plus five organizations; Sonoran Institute, Western Environmental Law Center, Future West, the Craighead Institute, and Headwaters Economics. The goals of this effort are to help people better understand the need and context of the line, to address the economic costs and benefits of the line, and to give people a way to have their values and concerns heard and considered in decisions about where the line should go.

Funded by NorthWestern Energy, the state of Montana, counties, and foundations, The MSTI Review Project involves an economic analysis by Headwaters Economics as well as a map-based spatial model developed by the Sonoran Institute and the Craighead Institute. The spatial model incorporated engineering concerns, and included separate analyses of potential impacts to both wildlife and community values.

With respect to the MSTI line, the economic analysis addressed questions as to who would pay for the construction of the line, what would be the tax benefits to local counties, and how private property values would be affected. The costs of construction will be covered by a "participant funding" model—which passes costs onto electric customers. Tax benefits to local communities vary by how much of the line passes through and according to the area's existing tax base. Impacts to property values vary according to the type of use of the property and the placement of the line. Small, rural residential parcels may face more risk of property devaluation from an overhead transmission line than other property types.

The spatial models found that co-location with existing power lines or highways is important from both the wildlife and community perspective. Both the wildlife model and the community values models placed a high priority on aligning the route with existing infrastructure, thereby leaving large blocks of undisturbed habitat intact. The wildlife model favored a route that is approximately half on private land, half on public land—reflecting the high quality habitat in each ownership type. The community values model placed an emphasis on protecting private property, agricultural lands and residential areas—suggesting a route primarily (70%) on public land.

The MSTI Review Project has demonstrated that it is possible to collect robust stakeholder input in a transparent, meaningful way. This type of process is valuable for informing infrastructure projects, and ideally would be conducted as early as possible in project planning. The findings of the MSTI Review Process can help inform comments to the EIS. Future projects may benefit from a similar analysis prior to embarking in the EIS process.

Status

In October, 2012, NorthWestern Energy decided not to move forward with MSTI after the Bonneville Power Administration, a potential partner in the MSTI line, chose to prioritize other transmission projects. NorthWestern Energy also cited other issues that influenced this decision, including environmental concerns for sage grouse and complications with federal permitting.

Resources

Organizations: Northwestern Energy; Bonneville Power Administration, Madison County, Montana; Jefferson County, Montana; Sonoran Institute; Future West; Western Environmental Law Center; Craighead Institute; Headwaters Economics
Location: Montana, Idaho
Planning phase: Pre-planning (Siting, community involvement)
Written by: Alison Berry – This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Last Updated: November 5, 2012

PowerLine Return-Icon