RTD's manager of the FasTracks program, which last week jumped up in cost to $7.9 billion, has resigned to take a job offer with a private firm.

Liz Rao will leave RTD Sept. 26 to become national transit development director in the Denver office of HNTB Corp. Rao said Sunday it is a vice presidency position that she couldn't turn down.

She said she was recruited for some time by HNTB, and her departure isn't related to the budget problems FasTracks is going through.

"It's really an opportunity that's up my alley because I will be developing transit opportunities for other transit agencies, clients of the company, to develop their programs," Rao said.

When voters approved a sales tax increase for FasTracks in 2004, the expansion of rapid transit corridors with another 122 miles of rail transit was to cost $4.7 billion. RTD blames unprecedented spikes in the costs of commodities such as steel, copper, concrete and fuel for the 68 percent increase in the program.

Combined with lower-than-projected sales tax revenues, RTD is in a bind because it isn't bringing in enough money to pay the higher costs.

Last week, Rao made the presentation to the board of three proposed alternatives, none of which has yet attracted much support from elected officials or the community:

RTD intends to hold public meetings on the issue and make a recommendation to its board in November.

Rao said she's not leaving because of the problems.

"We do have challenges with FasTracks, but I'm not leaving because of that," she said. "I know the leadership we have at RTD and in the region will get through the challenges whether I am there or not. It's something everyone across the United States is facing, cost increases and declining revenues.

"FasTracks will move ahead in whatever direction the board and the region decides. I know in my heart the region will find a solution."