Risk: Cost overruns. Cost estimates for a light rail project in Denver went from $4.7 billion to $7.4 billion this year, according to a spokeswoman for the Denver rail expansion project. For the Clifton Corridor, cost estimates have already risen $600 million from a previous estimate of $998 million. In 1999, MARTA went back to Congress for an extra $26 million — a 7 percent overrun — to finish the line to North Springs.
Next steps: Environmental impact statement and preliminary engineering, which are necessary to apply for federal grants, then final design, then construction.
Finish line: If funding is available, the first phase at least could be done within a decade; if the board does not approve the plan for expansion, back to the drawing board.