Bridge opening restrictions for "extreme" weather:
The Hour
"Extreme" is considered above 85F. I live near Savannah. That ain't extreme, but I understand the engineering principle and caution given the bridge's age.
Also of interest is the number of times it opens.
Heat stroke for Norwalk Bridge
When the mercury climbs, don’t expect the Walk Bridge in Norwalk to open for passing vessels.
Out of caution, the state Department of Transportation has chosen to keep the 119-year-old railroad bridge closed in hot weather— temperatures above 85 degrees — to avoid potential malfunctions that could disrupt Amtrak and Metro-North Railroad New Haven Line trains.
“The Walk Bridge was restricted from opening yesterday and today because of the heat. That restriction will be lifted at 9 p.m. tonight,” DOT spokesman Judd Everhart said Friday. “Going forward, we will not open the bridge when temperatures are above 85 degrees.”
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The DOT has been cautious about opening the bridge after it failed twice in spring 2014, prompting state, regional and federal officials to assemble money and begin planning its replacement. Design work is 30 percent complete and the state hopes to begin the estimated billion dollar project in 2018.
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Devine Bros., which moves heating fuel, concrete, and mason and landscaping materials by barge to its facility at 38 Commerce St., hasn’t had its traffic interrupted yet, said company President Thomas Devine.
“We got barges in this week so were pretty much set. It didn’t affect us in any particular way,” Devine said of the bridge being closed Thursday and Friday. “I would imagine they would close only during the height of the heat during the daytime. I don’t see any reason it would be closed at night.”
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In 2013, the DOT opened the Walk Bridge 270 times, or roughly 22 times a month on average. In 2014, the bridge was opened only 66 times. From January through July 2015, it was opened 79 times, according to the DOT.