New Jersey Gov. Christopher Christie (R) has thrown an ice-cold bucket of water on the heads of the sleeping Rip Van Winkles in New York and New Jersey. These folks trusted the planned commuter-rail Hudson River tunnel was somehow beyond the reach of the current backlash against government spending and deficits. However, that exemption has turned out not to be the case in the bitter election season just concluded.

The project’s construction packages, several of which had been awarded, included an underground addition to Manhattan’s Pennsylvania Station and a bridge on the New Jersey side. We believe the project eventually must be built; one of the two other rail tunnels under the Hudson is 100 years old.

What has happened instead is that everyone is playing games with the numbers.

The only way ordinary citizens could calculate the tunnel project’s cost is if they compared numbers quoted by Christie with those from mostly Democratic tunnel proponents.

If so inclined, here’s what they were faced with. On the project’s website, arctunnel.com, the project price is $8.7 billion. Christie cited a report from the project steering committee that puts the range at $8.7 billion to $10 billion, while the Federal Transportation Administration staff had it at $10.9 billion to $13.7 billion. Then the U.S. Transportation secretary, Ray LaHood, said in a statement the most the project would cost is $12.7 billion, with a low-range cost of $9.8 billion, a middle range of $10.9 billion and a high-end range of $12.7 billion.

Finally, U.S. Sen. Frank Lautenberg (D) said he had confirmed that the most reliable cost estimate was $9.7 billion, excluding the New Jersey bridge.

The Big Dig in Boston should have put an end to the mystification and spinning of infrastructure budgets in which big projects start life at the lowest possible cost within the narrowest possible scope with no mention to taxpayers of the risk of potential overruns.

Apparently not. Now that the Republican backlash has weakened the Democrats’ tenuous grip on Capitol Hill, be prepared for a broader assault on all kinds of economically crucial public works.

Earlier this year, Benjamin Cheatham of McKinsey & Co. in these pages called for a non-political prioritization of vital infrastructure, mainly by force rankings based on an assessment of economic returns. Cheatham also suggested the administration create an independent panel to develop just such a prioritized list of critical national projects.

We have one more idea: Put all the cost information, including inflation factors, scope changes and contingencies, in the public domain. Include estimates of the benefits of projects over their life span, as well. In this digital age, the public demands a new level of transparency that makes clear the real cost information—information politicians prefer to keep to themselves.