The new completion date is two years beyond what officials had projected in 2011, which had the finished product done in 2042 without additional money.

Fastracks a multi-billion-dollar project to build rail projects and bus-rapid-transit around the Denver metro area.

In 2004, voters were promised a full-rail system around the Denver region by 2020, but the project has fallen behind schedule due to increased costs and lower than projected sales tax revenue. RTD's board of directors rejected asking voters for a sales tax increase this year.

"Because we are not assuming a sales tax increase, what we have to do is model the financial plan to show how the cash flow works, and when the last part of Fastracks will be done and that's 2044 now," Fastracks Spokeswoman Pauletta Tonilas said.

Tonilas says the only way to move the project along faster is to find more money.

"As we continue to build this program out with the revenues we have," Tonilas said. "The longer you stretch the program out, the more it's going to cost."

Tonilas says RTD is looking for alternative ways of funding, like federal grants, and bids like one the agency received on the Interstate 225 section of rail line through Aurora from Kiewet Infrastructure Company. The agency has asked for other proposals to compete with Kiewet's offer, Tonilas says.

"In mid-June, we'll be getting those proposals back to see where that lies," she said.

As for other portions of Fastracks, RTD announced the West Rail Line will open on April 26, 2013. The West Rail Line is the first FasTracks project to be completed eight months ahead of schedule.

Crews are finishing construction on the 12.1-mile light-rail line that will take commuters from Denver Union Station west, through parts of Denver, Lakewood and the foothills of Jefferson County to the Jefferson County Government Center in Golden.

Out of the 12 planned FasTracks projects, there are eight currently under construction including the redevelopment of Denver Union Station and its surrounding site, I-225 extension to Illiff Avenue, the Eagle P-3 Project, which includes the East Line to Denver International Airport, Gold Line to Arvada; and the first segment of the Northwest Rail Line to south Westminster, the North Metro Rail Line to the National Western Stock Show; and the express lanes extension on US 36 for Bus Rapid Transit.