WPCNR’S THE DAILY BAILEY.  News & Comment By John F. Bailey. August 2, 2007 UPDATED 2:31 PM EDT: The shocking, unexpected descent of the I-35 West Bridge (in Minneapolis, Minnesota) into the Mississippi River yesterday – which began life in 1967 – eight years after the Tappan Zee Bridge opened – should be a sobering wake-up fall to the Department of Transportation, the MTA and the New York State Thruway Authority and the Port of New York Authority bridgemasters, too -- as well as county leaders in Rockland and Westchester County.

How Safe Is the Tappan Zee Bridge Now?

Donna Greene, Assistant Communications Director for Westchester County gave County Executive Andy Spano's reaction to the Minneapolis collapse in a statement: "I have been assured by the Thruway Authority that the millions of dollars that have been spent on the bridge ensure the safety of it. However a long-term solution obviously is needed." Greene assured WPCNR that "The county executive, of course, will stay on top of it through his many conversations with key state officials, his TZB Task Force and his work with  NYMTC (the NY Metropolitan Transportation Council). 

The makeshift repairs on the TZB have been going on for years. How long will the new TZB deck last? How long can it be expected to support traffic while a replacement is built?  What has to be done now to buttress the present structure? Does the structure need to be reinforced?  And does the present support structures need work? These are questions the DOT needs to answer in light of the Minneapolis bridge failure.  We the trusting public always assume the professionals know their bridges.

The DOT is currently replacing the deck over a two-year schedule that will replace 40% of the entire deck. This was what Minnesota workers were doing on the Minneapolis Bridge that collapsed yesterday, after declaring the steel support structure fatigued but having no cracks, according to news reports. So what happened? This will be very instructive.

According to the New York State Thruway news release this spring on the deck replacement, “The deck replacement project, expected to take place over a two-year phased schedule, will replace approximately 40% of the entire deck. This portion of the deck, including the west end of the bridge and the main truss, is in the most need of work and is therefore the most critical to replace. In previous years, the Authority replaced half the length of the center lane of the causeway and the entire east truss deck.”

Years ago a pal and I were heading across the George Washington Bridge on our way West. I remarked to Paul, noting the age of the George Washington Bridge (1931), how do they know this is safe? Paul said, “they inspect it.” We both laughed uneasily. But does the Minneapolis collapse say something about overall structure soundness the engineers did not know? Can it all go at once?

The Mianus River Bridge Collapse Revisited

A reporter who covered the Mianus river bridge collapse in   Greenwhich, Connecticut on the night of June 28, 1983, recalled that when that bridge collapsed it was a section of the bridge that fell due to a joints problem. She expressed interest that an entire structure collapsed in the Minneapolis case.

The Mianus River Bridge, Greenwich, Connecticut.

More sobering is that the engineering firm was not found to be at fault in that accident and the State of Connecticut eventually settled suits with the three persons killed in that collapse. According to United Press International dispatch of May 25, 1984, the state of Connecticut did not distribute Federal regulatory guidelines that could have made state inspectors "aware" of problems leading to the collapse.

The National Transportation Safety Board said that the manuals "remained in supervisors' bookcases and were not available to maintenance inspectors," in a preliminary report. UPI, in addition pointed out that the NTSB preliminary report "drawn from four days of testimony by engineers, officials and witnesses," that  "the  (Connecticut) state officials were cited for not alerting inspectors to the inspection procedures for pin-and- hanger structures and for not maintaining an inspection schedule."

Well, persons who use the Tappan Zee Bridge every day have to be asking themselves how good are the inspections of the TZB? We have had a lot of suggestions that it needs replacing. Why does it need replacing? And how worn out is it?

Should shore-up supports be constructed right away on the suspended portion of the TZB? This is no longer a question of what shall we do to replace the bridge? In light of the Minneapolis bridge failure, the analysis of the Tappan Zee structure has to address the question of how safe is it now? And why is it safe? And how can we be sure it’s safe?

Previously, the information on replacing the Tappan Zee Bridge was not one of safety. The Tappan Zee Bridge website says the bridge is inadequate for present traffic needs, reporting, “More than 135,000 vehicles cross the 3.1 mile Tappan Zee Bridge every day, with volumes as high as 170,000 vehicles daily. If nothing is done to relieve congestion in the I-287 corridor between Suffern and Port Chester, by 2030 traffic crossing the bridge will increase to 200,000 cars per day. Travel times are expected to grow significantly.”

The Tappan Zee Bridge website (www.tzbsite.com) acknowledges the old TZB has problems, to wit: “The Bridge does not meet current seismic criteria… Although the bridge is safe, due in large part to a rigorous program of maintenance and inspection, it is nearing the end of its service life.”

The website elaborates on the bridge “problems,” emphatically stating: “Yes, the Tappan Zee Bridge is safe. The New York State Thruway Authority operates a regular program of scheduled maintenance designed specifically to ensure the bridge is safe for travel. The bridge also receives a detailed inspection every two years by qualified engineers.”

The Westchester County Department of Communciations  in their statement above did not address whether the county was going to ask for an update of bridge conditions in light of the totally unexpected failure of Minnesota’s “safe” bridge – declared safe with a bit of “fatigue” last year, according to media reports.

More than ever the rebuilding of the bridge has to stop becoming a political issue and become a safety issue.

If it were up to me I’d say the present bridge has to be repaired extensively immediately from a support standpoint. Admittedly, this is not the same structure bridge that fell in Minneapolis. But how safe is it, anyway? And we are not talking about the lack of breakdown lanes, the movable media barrier or the lack of speed enforcement on the bridge. (That’s another column).

Can you imagine the disaster if this bridge collapsed? In loss of life immediately? And long term – the commuting nightmare as all traffic diverted to Newburgh Beacon Bridge, the Bear Mountain Bridge and the  George Washington Bridge?

As of this hour the New York State Thruway Office of Public Affairs has not responded to WPCNR questions about their Tappan Zee Bridge safety program effectiveness, whether they plan to take a more detailed look at the bridge, and how long the bridge will last after the deck repair.

I think the Thruway engineers have to be having sobering thoughts this morning.

I would.

And I’d be going over that bridge with a fine tooth comb.

Right now.