Since the proposed new Tappan Zee Bridge , talk of construction and cost have commandeered bridge discussion.
But on the sidelines remains a paramount topic and the reason for the $5.2 billion undertaking—the current span's deficiencies.
In an informational packet released after the federal government added the Tappan Zee to the construction fast-track, officials spotlight the crossing's shortcomings—and they're manifold.
"The existing Tappan Zee Bridge falls short of current engineering standards," the outline reads. "In addition, an extensive and costly maintenance and capital program has been required to keep the bridge’s structural elements in a state of good repair."
Between 2000 and 2010, the New York State Thruway Authority spent $500 million in bridge maintenance. To continue for another ten years would run about $1.3 billion, officials reported.
The bridge's failing were identified in full in the 1980s, and were swiftly followed by a comprehensive repair program that continues to this day. Columns, steel and other facets were swapped out for newer material. In 2007, construction crews upped the maintenance to match increased deterioration.
The span's weaknesses are particularly unsettling due to its classification as a "critical bridge," or route that must remain open are an earthquake or similar disaster to serve emergency vehicles. "The Tappan Zee Bridge lacks structural and operational redundancy to easily sustain extreme natural events such as hurricanes and earthquakes or man-made events such as fires or vessel collision," the report reads.
Currently, the bridge sees about 135,000 vehicles daily, and accommodated close to 45 million in 2010 alone.