America’s infrastructure is crumbling. And the problem is more severe than you probably realize. Yes, you know about all the unfilled potholes and bridges in disrepair. But there are things you can’t see—like a decades-old air traffic control system, and storm drains from the 1930s—that are in even worse shape.

In a rational political environment, Congress would respond by passing an infrastructure bill that allocated new money, even if meant deficit spending. There are still lots of construction workers looking for work, after all, and borrowing is cheap, thanks to low interest rates. But Republicans have blocked such proposals. The best lawmakers can do, it seems, is to keep funding infrastructure at current levels. To do that, they must come up with some way to replenish the federal Highway Trust Fund, which is running short on money.

Unfortunately, they can’t even get this part right. There are now three Highway Fund proposals under consideration in Congress. All of them are bad.

The Trust Fund provides money for road construction and mass transit. At the moment, it gets money from the federal gas tax. But the tax is not indexed—in other words, it doesn’t rise automatically with inflation. For many years, that wasn’t such a big deal. Revenue from the gas tax outpaced spending, creating a surplus. But as inflation eroded the real value of the tax, that surplus became a deficit. Since 2008, lawmakers have transferred $54 billion from the Treasury’s general fund to the trust fund, just to keep it flush. But the fund is expected to run out sometime this summer. If Congress does not act, it will face a $12 billion shortfall in 2015 and $164 billion shortfall over the next decade—and those crumbling roads will crumble even more.

Finding that $164 billion won’t be easy. Republicans, who have no problem passing corporate tax breaks that increase the deficit, will surely insist that Congress find some way to offset the new spending. Similar demands scuttled proposals to extend unemployment insurance—and that $9.7 billion pricetag. That’s led to three bad ideas: