When Sacramento County officials gave the go-ahead to spend a billion dollars on a fancy new airport terminal in 2006, local and state economies were humming, and the airport's passenger traffic had topped 10 million a year and was rising.

As Sacramento International Airport's state-of-the-art and art-filled Terminal B opens this week, however, the economy is in the dumps and its passenger count has declined by nearly 20 percent.

That raises a question:

Was the decision to build the terminal a wise investment in the future that will pay tangible dividends for California's capital city, or an expensive exercise in political grandiosity?

The airlines didn't support the county's go-for-broke approach to replacing a 4-decade-old, outdated terminal, citing costs that they and their passengers would bear. They would be much happier to be paying for a replica of the more modest – but handsome and perfectly serviceable – Terminal A that opened in 1998.

Local officials, however, decided to make a statement by approving a Terminal B they said would impress visitors and generate positive economic effects, dubbing it the "Big Build."

We won't know for many years whether it's a big boon or a big boondoggle, but there are reasons to be skeptical.

The economy shows no overt signs of recovery, Sacramento has been hit particularly hard by the housing meltdown, the region's governmental employment base is in decline, and the era of cheap airfares may have flown its course.

Whatever symbolic impact it may have on Sacramento, Terminal B is also emblematic of the troublesome issue in any major public project. The financial commitments are huge and lead times are measured in years or even decades, but underlying assumptions can change rapidly.

Sometimes they pay off. There was much skepticism about building the Golden Gate Bridge and the San Francisco-Oakland Bay Bridge – simultaneously – in the midst of the Great Depression, for example, but they have been spectacularly successful.

Sometimes they don't. We know now that spending tens of billions of dollars to build and operate new prisons in the 1980s and 1990s was, for the most part, money down the drain. We would have been better off putting that money into better policing, drug treatment and juvenile delinquency prevention.

Sacramento faces the same basic issue in deciding whether to build a new sports arena. And it's the central issue in the highly controversial, extremely expensive proposal to build a bullet train system linking the state's northern and southern regions.

Ironically, the rationale for the bullet train is that airports will be incapable of handling California's ever-increasing demand for intercity travel – a market, however, that's going the other direction these days.

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Call The Bee's Dan Walters, (916) 321-1195. Back columns, www.sacbee.com/walters.

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