Trans-Allegheny Interstate Line Co.(Greensburg, Pennsylvania, U.S.), a subsidiary of Allegheny Energy Inc., has filed an application with the Pennsylvania Public Utility Commission seeking authorization to build a 500-kV and three 138-kV transmission lines to ensure reliability of the electric grid in southwestern Pennsylvania. The lines are required to serve local need in Washington and Greene counties.

Independent experts have determined that growth from the expanding Pittsburgh suburbs and accompanying commercial development has strained the system. They agree that if the lines are not built, area residents and businesses will experience reliability problems that could result in blackouts or brownouts in several years. The new transmission lines have planned in-service dates ranging from 2009 to mid-2010.

"This project is key to our mission of providing southwestern Pennsylvania with reliable electric service while meeting growing demand," said David E. Flitman, president of Allegheny Power and Trans-Allegheny Interstate Line Co. "The new lines will ensure the continued viability of the local grid, keeping the lights on for years to come."

According to Trans-Allegheny Interstate Line Co., there are other benefits as well including:

• Assuring reliable service necessary to attract industry and support development
• Expanding markets for local coal
• Potential for new generation projects, including clean-coal technologies.

The proposed route for the 500-kV line starts about a mile north of the Pennsylvania-West Virginia state line near Mt. Morris, and runs 36 miles (58 km) north to North Strabane Township. The 500-kV line and connected 138-kV lines will be built primarily on company-owned rights-of-way.

"We determined our proposed route after careful study, which included the analysis of valuable input we received at public open houses," Flitman said. About 2200 individuals attended Allegheny's 12 public open houses. The purpose of the sessions was to show potential routes and collect feedback. The company's routing team heard remarks from residents who scanned detailed aerial photography showing homes and other landmarks, and also considered hundreds of written comments to create the best possible route for the line.

The proposed transmission lines in Pennsylvania are part of the Trans-Allegheny Interstate Line (TrAIL) project. TrAIL also includes a second 500-kV line necessary for regional reliability, which will span Allegheny's service territory from a new substation near Mt. Morris, then across West Virginia to Northern Virginia.