The Federal Transit Authority has accepted the environmental study of the $452 million line from Kennecott Land Co.'s Daybreak development to the existing north-south TRAX line at Murray. On Monday, UTA announced hiring of a consortium of three construction and engineering giants - Kiewit, Herzog and Parsons - to design and build the 10.6-mile spur from the 6400 South station.

The federal approval and a possible opener by 2010 or 2011 come as a relief to local officials who for years have complained of inadequate service between the valley's east and west sides.

"We desperately need east-west transportation on something besides gridlocked streets," Midvale Mayor JoAnn Seghini said.

UTA proposes to build the line with half federal and half local funds, including proceeds from a sales tax that Salt Lake County voters approved last year.

Seghini said the rail line will help draw sensible development to former industrial areas. Likewise, Murray Mayor Dan Snarr said the prospect of more riders through his city likely will intensify development interest. "There's a lot of underutilized properties," he said.

In the broader sense, Snarr said linking the growing west suburbs by rail is necessary to retain a high quality of life and improve the valley's air.

"I just believe the future can be best addressed by realizing you can't outpace the population increase with new roads," he said.

At the planned link's southern terminus in the new Daybreak development, Kennecott Land vice president for long-range planning Jim Schulte said prospective residents are counting on a rail link. The neighborhoods are linked to trails and designed for walkability.

"There's a certain lifestyle that people who buy in Daybreak are looking for," he said. "There's a sensitivity to sustainable development philosophies that many of our buyers embrace."

bloomis@sltrib.com