Lost in the debate about transportation spending is that nobody agrees on how to rate the condition of the nation's aging roads, bridges and railways.

With Washington focused on ensuring the Highway Trust Fund doesn't run dry, transportation officials and advocates say there is a real need for a more uniform barometer to assess the quality of the nation's infrastructure.

A new report from the White House, for example, claims that 95 percent of Washington's roads are in poor condition.

Pretty scary, right?

Well, that figure was news to D.C. transportation officials, who say that roughly 37 percent of the city's roads are in poor condition or worse. Just 9 percent of federal roads in the nation's capital were labeled that way.

“Those numbers were quite surprising to us,” Muhammed Khalid, interim chief engineer at the District Department of Transportation, said of the White House report. "Even if we [average] the local and federal [roads], I'd say 23 percent would be rated poor."

For context, California has notoriously suspect roads but only 34 percent were labeled poor. D.C.'s smaller size is partially responsible for the eye-popping number, officials said, but even a state like Rhode Island had just four in 10 of its roads considered poor.

If that's not confusing enough, the American Society of Civil Engineers says 99 percent of D.C. roads are in poor or mediocre condition, whereas TRIP, a national transportation research group, estimates one-third of major Washington-area roads are in poor condition.

“That might be one of the challenges — it will have to be addressed down the road,” added DDOT spokesman Reggie Sanders of how various groups label road conditions. “You might get a pretty diverse group of responses. I’m not so sure the people would know how to respond to 95 percent.”

There are similar discrepancies in how the groups categorize road conditions in most every state.

In neighboring Virginia, the White House estimates that 6 percent of roads are in poor condition; ASCE says that 47 percent of roads are in poor or mediocre condition.

In Maryland, the White House placed 20 percent of the state's roads in the poor-condition category; ASCE said 55 percent are in poor or mediocre shape.

The ASCE does not differentiate between poor and mediocre in its snapshot, meaning more roads are identified as needing help, whether the road is falling apart versus passable.

Some of the measures don’t even account for the same roadways, analysts said.

“That figure doesn’t include all the roads,” said Clark Barrineau, an ASCE spokesman, explaining the White House report. “It can be confusing.”

While this debate sounds like inside baseball, it’s of critical significance.

Republicans and Democrats both agree on the importance of infrastructure spending. But they have different ideas on how much money should be pumped into repairing roads and bridges.

The White House continues to push for a stimulus-style program, and Republicans routinely dismiss such a blueprint.

For lawmakers to agree on a long-term bill on infrastructure spending, there needs to be some consensus on the scope of the problem.

“The president is right: Both Democrats and Republicans agree that we need to have the best roads possible,” said one House GOP staffer who works on transportation issues. “But we always assume he is framing things in the worst possible light just to bolster his agenda.”

When asked about the the various road ratings, the official replied, "It's a bit all over the map. There's no real gold standard. That's a problem."

And it remains a mystery whether the numbers will ever match up.

“We need to have a conversation with the [Obama administration],” Khalid said, “to know which method they used.”