Home About TVA Power System Environmental Stewardship River System Economic Development Investor Info Newsroom

Cumberland-Montgomery 500-kV line & Oakwood 161-kV line

TVA announces preferred route for future 500-kV transmission line April 2005

TVA has identified its southern alternative as the preferred route for the new 500-kilovolt (kV) transmission line from Cumberland Fossil Plant to the Montgomery Substation. The 38-mile line would leave Cumberland Fossil Plant on the south side, turn east and cross the Cumberland River, then turn northeast and cross Interstate 24 before entering the Montgomery 500-kV Substation. The details of how the line will interface with the Montgomery County Industrial Park east of I-24 are being discussed by TVA and local community leaders. The line is targeted to be in service by November 2007.

image of 500kv tower

This is an example of a 500-kv tower built by TVA.

The line is needed to improve the reliability of the transmission system, reduce the possibility of power outages in middle Tennessee, and maintain stability at two TVA fossil plants.

TVA has also identified the need for a second transmission line to provided voltage support in the area west of Clarksville. The majority of this 13-mile-long, 161-kV line would be built along the path that had been identified as the northern route alternative for the 500-kV line. The line would leave the Montgomery substation heading north on existing right-of-way, turn west and cross Interstate 24, then continue west to Highway 41A north of Clarksville. It would enter the Fort Campbell Military Reservation and end about a mile south of the Screaming Eagles Substation, where it would connect to the Screaming Eagles tap line.

Maps

The maps below show the preferred routes for the 500-kV line (Corridor B) and 161-kV line (Corridor D). Click on the index map to find the number of the section map you’d like to see. The section maps are highly detailed and include the names of property owners along the proposed routes.

The maps are PDF files requiring Adobe Acrobat Reader. Use the zoom tool to view details of the section maps and allow time for them to reload. If you have questions or need help understanding these documents, please contact TVA (see contact information).

map of proposed transmission routes

Corridor D maps

Corridor B maps

Map D5 (800 kb)

Map D6 (500 kb)

Map D7 (216 kb)

Map B (240 kb)

Map B1 (172 kb)

Map B2 (192 kb)

Map B3 (192 kb)

Map B4 (356 kb)

Map B5 (412 kb)

Map B6 (600 kb)

Map B7 (296 kb)

Map B8 (188 kb)

Preferred Routes (PDF, 2.1 Mb)
This large map shows the entire length of both preferred routes. The Cumberland-Montgomery 500-kV line is shown in red and the Oakwood 161-kV line is shown in blue.

Need for the 500-kilovolt line

This fact sheet explains why the project is important to ensure power reliability and protect against outages.

Reasons for preferred alternative

The two alternative routes — northern and southern — were evaluated using the same environmental, land use, engineering, and cost considerations. The reviews were based on available data, aerial photography, transmission line routing criteria, public input, field surveys, and environmental data.

The southern alternative is preferred because it avoids the risks associated with the proximity of transmission towers near an aircraft flight path and training operation, requires no residential relocations, has fewer land use impacts, minimizes impacts to historic property, and minimizes reliability and maintenance issues that arise when transmission lines share the same transmission structures (a 500-kV line with a 161-kV underbuild).

Load growth map

The middle Tennessee and northern middle Tennessee area is growing faster than most other regions that TVA serves. Without a new line in the area, the projected load growth will cause low voltage under certain situations and will cause stability problems at TVA’s Cumberland and Paradise fossil plants. One result would be power outages affecting about 4,000 megawatts (MW) of load — about two million homes and businesses — in middle Tennessee. (1 MW serves 585 households based on the average annual use of all residential customers: 4,000 x 585 = 2,340,000). The line would provide stability for Cumberland and Paradise. (A plant’s generators must stay synchronized with other generators in the system. If not, they may speed up and cause damage.)

This would be the first 500-kV line constructed by TVA in about 20 years. TVA has supplied 99.999 percent reliable power for the past five years.

Both projects will benefit all of the middle Tennessee area, including Clarksville, Nashville, and surrounding cities.

Earlier documents on the project

Preferred paths (Oct. 2003)
Project description and maps (Oct. 2003)
Need for the project and preferred paths (Oct. 2003)
Questions and answers about the preferred paths (Oct. 2003)
Overview of the project (June 2003)
Questions and answers (June 2003)

Next steps

Property owners directly affected by the preferred route are being notified by mail. TVA will follow up with phone calls to answer questions. Right-of-way acquisition is scheduled to begin in summer 2005. Construction is expected to begin in winter 2006 and the project completion is scheduled for fall 2007. (Read a summary of TVA’s land acquisition process. PDF file, 22 kb.)