By Al Barbarino
On the five-year anniversary of a Minneapolis bridge collapse that killed 13 people, a bridge safety advocate has launched a website pinpointing what he believes are the inevitable sites of future disasters.
Author and construction lawyer Barry B. LePatner used data from a 2009 Federal Highway Administration report to map out nearly 8,000 bridges deemed both “structurally deficient” and “fracture critical” by the FHA.
The Google map used at SaveOurBridges.com includes some of the most well-known and heavily travelled bridges in the city, like the Brooklyn Bridge, with average daily traffic of 111,183 cars; the Robert F. Kennedy Bridge, with 80,800; and the bridge at FDR Drive and Harlem River Drive, with 61,022 in daily traffic.
According to LePatner, a structurally deficient bridge has one or more “major defects” in its support structure; while a fracture-critical bridge lacks redundancy, meaning that if one portion of the bridge fails, there is no “back-up.”
“Take out a deck of cards, build yourself a structure, pull one card out and see what happens,” LePatner, founding partner of New York-based construction law firm LePatner & Associates said. “Almost all new bridges today are designed with redundancies, but many of those built in the 1960’s and the 1970’s were built cheaply and quickly.”
The FHWA data LePatner used tracked America’s 600,000 bridges, finding 72,000 to be structurally deficient, 18,000 to be fracture critical. The 7,980 meeting both criteria are mapped on the website.
Many of these often older bridges were built with savings in mind over safety, bound to collapse unless proper maintenance, repairs, and in some cases replacement, are implemented, LePatner said.
But an official at the FHWA who was unauthorized to speak on the record said that LePatners’s thinking is “completely erroneous,” saying that he has misinterpreted the FHWA’s definitions for structurally deficient and fracture critical bridges.
Comparing the Minneapolis disaster to the state of the 7,980 bridges mapped on the website is an unfair comparison because the collapse was the result of an anomalous design flaw, the official added.
“Just because a bridge is structurally deficient it doesn’t mean it’s not safe,” the official said. “It just means that the bridge may be in need of repairs, or traffic restrictions, depending on the situation.”
“Fracture critical has nothing to do with the bridge fracturing,” the official added, conceding that such bridges do lack redundancies. “It means that the bridge was designed in a way where each member is critical to the bridge. It’s simply a term for the type of design.”
The I-35W Minneapolis bridge that collapsed had been ruled “structurally deficient” since 1991, but local authorities turned a blind eye to the problem, resulting in the ultimate loss of 13 lives and over 145 injuries, LePatner said.
But an investigation by the National Transportation Safety Board concluded that the “probable cause” of the collapse was “inadequate load capacity” due to a “design error of the gusset plates,” sheets of steel that connect a bridge’s beams and columns.
“You could build a bridge today and, if it has a design flaw, it could crumble in a week,” the FHWA official said.
However, the I-35W investigation also found that the “corrosion documented on the gusset plates” had been “overlooked or underestimated by bridge inspectors using visual inspection methods,” and the NTSB made safety recommendations asking the FHWA to require more in-depth inspections to detect gusset plate corrosion.
“Corroding, cracking” bridges make for a “toxic mix” when combined with inactivity in Washington and a lack of information out there to give citizens the information they need regarding bridge safety,” LePatner said. “The website is intended to begin a new dialogue, and for families on both sides of bridges to realize their children are crossing dangerous bridges.”
The National Bridge Inspection Program mandates that bridges receiving federal aid undergo routine inspections at least once every two years. The close-up, visual examinations include evaluation of a bridge’s major components and they are analyzed for their load capacity. Whether or not these inspections go far enough remains a point of contention.
LePatner did praise New York City for taking steps in the right direction, leading the pack by pumping money into bridge repairs and maintenance, and setting it apart from most other cities.
“The reality about New York City is, over the last 10 years, the administration has undertaken over $5 billion to New York City repairs, and as a result, by and large, New York City bridges are among the safest,” he said.
Incidentally, a federal study released last week (Wednesday) announced that the Tappan Zee Bridge, built in 1955, will be demolished in 2017 or 2018 when its replacement is completed.
