ORLANDO, Fla. -

The funding source for building and maintaining roads in Florida is in trouble. That's what a group of policy makers and business leaders is being told at a summit in Orlando, as the trouble beings with the car you are driving.

Cars are more fuel efficient, and getting better every year, but planners and road builders are concerned.

The cash for building and maintaining roads comes from gas tax collections, and with every extra mile squeezed from a gallon, collections are going down.

"State budget for transportation is $9.5 billion. So where do we find that money?" said Matt Ubben, of Floridians for Better Transportation.

How to better pay for roads and make sure everyone is paying their fair share is one of the topics at a leadership summit in Orlando.

"We have to openly replace the gas tax with something else because there is always going to be an incentive for us to have use fewer and fewer gallons of gas," said Adrian Moore, of Reason Foundation.

The obvious answer to making everyone pay is to charge by the miles you drive, but that idea is raising privacy concerns.

"Oregon actually has this system in place now and they have a choice: They can pay a flat fee, they can have their dominator read," said Moore.

As many as 10 million people are expected to move to Florida in the next three decades, and that makes stable funding crucial.

The U.S. Chamber of Commerce said one key will be to require the services we use be located near mass transit facilities.

"If we co-locate transportation and the services and the things you do in your daily lives, it's something that is going to improve the quality of life and reduce your cost," said Janet Kavinoky of the U.S. Chamber of Commerce.

The experts do agree that waiting for the cash to run out is only an option for gridlock in the future.

Experts say states have no more than a decade to decide how to pay for roads with dwindling gas taxes and be fair to everyone. The problem is especially acute for trucking companies, who need roads to survive.