The Federal Transit Administration (FTA) said Friday that it has approved preliminary engineering work on a new light-rail line that, if built, would become the third in the Twin Cities.

The 15-mile Southwest Corridor line would connect downtown Minneapolis and Eden Prairie. If the project continues to clear FTA hurdles and wins federal funding, construction would begin in 2014, with an aim of the rail line becoming operational by 2017 or 2018.

The corridor would run through Eden Prairie, Minnetonka, Hopkins and St. Louis Park before entering Minneapolis and connecting with the Central Corridor line, now under construction to link Minneapolis and St. Paul.

The Hiawatha line, which connects downtown Minneapolis with Minneapolis-St. Paul International Airport and the Mall of America, opened in 2004 and served 10.5 million customers in 2010.

"What this means in the eyes of the FTA is that we have a sound and viable project that will create jobs and benefit employers as well as those who live and work near the transitway," said Metropolitan Council Chair Susan Haigh. "The FTA's blessing is a very good sign."

Hennepin County Commissioner Gail Dorfman called the approval "an important milestone."

"The addition of the Southwest light-rail line will connect residents from throughout our metropolitan region to major job centers and key destinations throughout downtown Minneapolis, the central cities and western suburbs," Dorfman said.

For more information on the Southwest Corridor project, see www.startribune.com/a644.

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