The idea of rail service between Phoenix and Tucson has been under study for years but now there are some numbers to put to the project.

Despite previous studies of intercity and commuter rail between the two cities, the Department of Transportation still says the idea is in the early stages. And if it ever does get the green light, it won’t be cheap.

ADOT’s rail planning program manager, Carlos Lopez, says early estimates range from $4 billion to $10 billion.

The state has submitted preliminary draft environmental assessments to the federal officials in charge and expects to complete the draft report by this summer.

One source of funding could be the federal government, but Arizona would also have to cough up some cash. Federal grants would require a 50 percent match.

No need to get too excited about catching the next train.  Lopez tells the Arizona Daily Star even if the funding was in hand today, it would take 8-10 years to complete construction.