By Mike Leidemann
Advertiser Transportation Writer

There's a reason why many transportation projects seem too good to be true. They are.

That's not my opinion. It's the factual finding of a new comprehensive study reported last month in the Journal of the American Planning Association.

The study, conducted in Europe and North America, sampled 258 transportation infrastructure projects worth more than $90 billion and dating back nearly 90 years. It found some startling results:

• Costs are underestimated in nearly nine out of 10 projects. There's an 86 percent chance that any randomly selected government transportation project will end up costing more than officials initially tell the public.
• Actual costs ended up being an average 28 percent higher than estimated costs. Rail projects have the highest percentage of inaccuracies, 44.7 percent; road-building projects have the lowest, 20.4 percent.
• Things aren't getting better; estimates on current projects are no more accurate than they were 90 years ago.

The study concludes that taxpayers, almost always end up paying at least 20 percent above the initial estimate for any transportation project.

Government officials and their contractors lie about the planned costs to win public approval of their projects. They believe we will buy into their road and mass transit programs if we think they cost less than they actually do.

"Either the people who do the budgets are incredibly stupid, but this is highly unlikely," according to Bent Flyvbjerg, one of the study authors. "The other possibility is they manipulated the budgets to make sure the projects are approved."

First Flyvbjerg and his co-authors tried to examine other explanations. They looked at the possibility that most of the problems were simply honest mistakes, but decided if that was true, costs would be overestimated as often as underestimated. In fact, very few of the projects were overestimated.

Then they considered whether government officials might be overly optimistic or the victims of sloppy accounting. Again, the data didn't support that view, the authors said.

The only explanation that fit the facts was the officials were being dishonest with the public.

"Underestimating cannot be explained by error and is best explained by strategic misrepresentation, that is lying," the study said. "The use of lying and deception as tactics in power struggles aimed at getting projects started and making a profit appear to best explain why costs are highly and systematically underestimated in transportation projects."

So you might well keep this study in mind the next time some lawmaker says this new highway will "only" cost $100 million or some planner says that repaving work will only take a month to finish. Just remember: Buyer beware!

Reach Mike Leidemann at 525-5460 or mleidemann@honoluluadvertiser.com.