HARTOFRD, Conn. (CBSNewYork) – As Connecticut prepares to upgrade parts of its aging rail infrastructure, the biggest challenge will be replacing four swing bridges, WCBS 880 Bureau Chief Fran Schneidau reported.

WCBS 880 Connecticut Bureau Chief Fran Schneidau On The Story

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The bridges are in Greenwich (Cos Cob) and Milford-Stratford (over the Housatonic River), as well as Norwalk and Westport. They are over 100-years-old.

State DOT Commissioner James Redeker said the cost will likely be around $2 billion, and this will be no quick fix.

He noted that the work on the bridges must be done with as little disruption to Metro-North Railroad’s New Haven Line train schedule as possible.

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“Which is, in part, why the projects take long and cost as much as they do,” he told Schneidau. “We have very short windows of time at night or we have to take tracks out of service.”

“This is the busiest railroad in the country and to do work on that railroad and to sustain the operation at the level that it is is the challenge,” he added.

The commissioner said the bill will be paid with a mix of federal and state funds, but he said Connecticut’s traditional 20 percent share may be shaved since new regulations allow the state to tap a new source of federal funding.

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Would you like more service disruptions if the work could be done faster? Sound off in the comments section below.