Minnesota has unfinished business on transportation. Six years ago, the Legislature overrode a governor’s veto to temporarily shore up roads and transit. And last year, it authorized some extra borrowing for selected road projects. Still, the state expects to have only enough money to cover 60 percent of its transportation needs over the next 20 years.

A shortfall of that magnitude cries out for a comprehensive solution, one that Gov. Mark Dayton and the Legislature should be eager to address this year — if they can find the political courage.

Let’s be clear: This isn’t just about mobility. Transportation is the public foundation upon which private enterprise operates. There’s no way the state’s economy can grow, prosper and compete on a crumbling foundation that’s 40 percent weaker than it ought to be. There’s no way that Minnesotans can sustain their cherished quality of life with a circulatory system that’s no longer pumping. Jobs won’t come. People won’t stay. Access to markets, education, health care and to each other will diminish. That’s a sad legacy to leave our next generations.

Your first instinct might be to doubt all of this. You don’t have much trouble driving around your own town, after all, and even in the busy metro area, traffic congestion has eased a bit in recent years. But you’d be alarmed if you saw a map of the unstable and dangerous pavement and bridges all around you. Much of Minnesota’s infrastructure was built in a short span of years, in the 1960s and ’70s, and it’s all wearing out at the same time. Patching and mending will no longer do; many roads and bridges need to be completely rebuilt, starting now.

And there’s a concurrent problem: The funding mechanism no longer works. For 60 years, federal and state gasoline taxes were the primary revenue source for expanding and maintaining transportation. But now those revenues are declining sharply for two reasons: resistance to higher fuel taxes and the declining value of the tax itself. The rise of fuel-efficient cars, coupled with lifestyle choices that require less driving, have reduced the tax’s buying power by one-third over the last two decades. What’s good for the environment and energy conservation is bad for building and maintaining roads.

A deflated gas tax is no excuse for inaction, however. Other states are moving ahead to find other sources. Oregon has a pilot program that offers the choice of installing a device in your car that counts your driving distance and taxes you by the mile. For now, the mileage tax is restricted to 5,000 vehicles, but it’s generally considered the wave of the future if privacy fears can be overcome.

Until then, Virginia and other states are relying heavily on taxing the gross receipts of oil companies for fuel shipped into local stations. The higher wholesale cost could be passed on, although the retail price would be subject to market pressures. Another idea is an annual tonnage-mileage fee based on a vehicle’s odometer readings and weight. Cobbling together a number of these approaches along with what’s left of the gas tax seems a likely solution, at least in the near term.

On the transit side, the metrowide sales tax is by far the most popular source nationally. But the quarter-cent sales-tax increase passed in 2008 for the Twin Cities allows for only a fraction of the investments that competing cities make. And the tax fails to meet higher transit demand as the market shifts toward closer-in living and less driving.

Indeed, at five recent public listening sessions around the metro area hosted jointly by Transportation Commissioner Charles Zelle and Metropolitan Council Chair Susan Haigh, the overriding plea was for better pedestrian, bike and transit connections. “That was the story even in the suburbs,” Haigh said. And Zelle, who hosted dozens of sessions across the state last year, reported similar reactions in smaller communities.

Another change Zelle noticed is that Minnesotans no longer complain about someone else grabbing all the transportation money; now they see that no one is getting enough. “That’s a game changer,” he said.

Zelle and Haigh aside, the biggest shortfall in transportation may not be money but leadership. The governor and Legislature should know that kicking the can no longer works; MnDOT has reached its borrowing limit. Dayton, legislative leaders and hesitant business executives should join the robust Move Minnesota coalition that unites business, civic and environmental leaders from 120 organizations to push for a real solution.

Maybe the public can’t yet detect the deterioration of our transportation infrastructure, but that doesn’t make it any less real. We’ve lived the Minnesota “good life” on the wise investments of those who came before us; now it’s our turn.