Don't wait to replace Tappan Zee

It's time for some serious bridge-building -- not in Washington, although that would be nice too, but over the Hudson River.

The Tappan Zee Bridge, a linchpin of the regional economy, is living on borrowed time. Built on the cheap and designed with scant margin for error, the 56-year-old span is no longer worth the cost of maintenance and upgrades. The bridge deck has deteriorated, beams are cracking and the support structure is seismically inadequate. Pilings on the Rockland County side weren't sunk into bedrock, and are vulnerable to decay.

Yet letting it deteriorate until it becomes unusably dangerous is unthinkable.

When the bridge opened in 1955, it was more than ample for the 18,000 vehicles that crossed daily. Today the figure is 140,000. With more than 50 million crossings annually, the 3.1-mile Tappan Zee is busier than the Queens-Midtown, Lincoln or Holland tunnels.

This isn't just an issue for Rockland and Westchester counties, which the bridge connects; without a well-functioning Tappan Zee, the entire region suffers. That's why state Sens. Dean Skelos (R-Rockville Centre) and Charles Fuschillo Jr. (R-Merrick) last week toured the bridge. Skelos is Senate majority leader; Fuschillo chairs the transportation committee.

But it will take Gov. Andrew M. Cuomo to power a new bridge across the Hudson. In his campaign, Cuomo called the Tappan Zee the biggest new transportation project on the state's agenda, and said any new administration must promptly choose a bridge plan and figure out how to pay for it. After election, he surveyed the bridge by tugboat.

The time for gubernatorial action is now. In addition to age-related disorders, the bridge is inadequate to today's needs, never mind tomorrow's. It has no breakdown lanes, for instance, while averaging three accidents a day, so tie-ups are routine. And there is no adequate provision for mass transit, which planners consider vital for handling growing trans-Hudson commuting without intolerable delays.

Almost everyone agrees that what's needed is a new bridge. State planners, local and regional politicians and, most of all, commuters have known this for years, thanks in part to an incredible $83-million worth of analysis and input. Indeed, the Tappan Zee is the poster-bridge for the difficulty and expense of getting anything built in New York. Projects are studied to death, easily delayed or derailed by the inevitable community opposition, and absurdly expensive, in part due to antiquated state laws.

Yet the state's economy depends on finding a way to overhaul New York's aging infrastructure -- and the Tappan Zee is a great place to start.

The problem is cost. A strong new bridge with dedicated bus-ways to seriously boost capacity -- rail is probably unworkable for reasons of expense and terrain -- would be $9.3 billion.

It's no surprise that politicians seem eager to call for a new bridge, yet awfully vague on how to pay for it. Public-private partnerships are often cited, but while bringing in business to build or even operate the bridge can introduce vast expertise that will help control costs and reduce political interference, it's unlikely to lower the price by much.

Let's get serious. The current car toll is just $5 round-trip. Set tolls at an average of $8 each way -- less for cars, more for trucks, with a rush-hour differential as well -- and you've got two-thirds of the annual debt service on bonds for a new bridge. The higher tolls won't slash crossings much because there are few alternatives. And since the Tappan Zee is a link in the interstate highway system, some federal money ought to be available, perhaps even enough for the remaining third.

Of course cost overruns are likely, and money will have to be found for maintenance. The point is, the cost is not insurmountable. But the river will be, at least from the jammed George Washington Bridge 24 miles south to the small Bear Mountain Bridge 29 miles north -- if the Tappan Zee is someday found to be so unsafe it has to be closed. In that case, every alternative will be a bridge too far.