Plans for the 70-mile SMART rail line connecting Larkspur to Cloverdale moved ahead this week unchanged and on schedule. But right now those plans are riding on hope ? several to be exact.

• Hope that the economy will improve and turn around a projected $46 million shortfall ? over the next 20 years ? in revenue generated by the quarter-cent sales tax that voters approved to pay for the rail line.

• Hope for a rebound in the still-anemic bond market, which, if unchanged, could leave SMART well short of the funding needed to build the entire system by 2014 as planned.

• Hope that SMART operators will be able to find other sources of revenue to offset an overall $154.7 million shortfall in revenue created by the factors noted above and by increased costs.

• Hope that operators will be able to find a rail-car manufacturer willing to build a lighter European-style rail car, which SMART directors say is quieter and more stylish than the American-style heavy rail car alternative.

• And hope that if they do find such a manufacturer, they will be able to get the waivers they need from the federal government concerning crash and emission standards and, if the builder is European, to overcome political pressure to buy American.

It?s possible that all of these will evolve into realities. And given that there?s time to wait, SMART directors wisely decided this week not to make any changes in the rail plans and let those hopes ride.

But it?s also important to get all the facts, fears and options out in the open now so there are no surprises in the future. This apparently was the thinking of the SMART citizen advisory committee, which encouraged the SMART board to be transparent as possible in talking about backup plans.

If little changes, the train would have to push back its projected start-up date from 2014 or consider phasing in the system. If SMART chooses the later option, it means delaying construction on some northern portion of the line, possibly from the Jennings Avenue stop in Santa Rosa near Coddingtown north.

Cloverdale City Councilwoman Carol Russell blew a fuse at this suggestion this week and convinced SMART directors to take out any wording of such a backup plan from the agency?s strategic plan.

We have no problem with that. There?s no real need to put these possibilities in that document for now. As long as they are out on the table somewhere.

No amount of disappointment and frustration can change the facts. Nor should it prevent SMART from making the difficult but necessary choices concerning rail cars and rail construction if the budget picture doesn?t improve.