On a mid-January afternoon, most of the pieces of the Wittpenn Bridge deck were fitted together near the Columbia River. Set on pilings, the deck rose in the air, caked in snow and ice while a dozen workers clambered around and underneath.“They were out here when it was nine degrees on Friday,” said Greg Arnold, the 56-year-old plant manager. “We’re so used to being in it that we don’t look at (the weather forecast) in the morning.”For the past two years, workers at Vigor Industrial in Vancouver quietly assembled the massive bridge deck at a warehouse at the Columbia Business Center. About 400 workers have had a hand in its making. This spring the deck will be broken into three pieces, then barged through the Panama Canal on the way to New Jersey.It is one of the biggest items manufactured in Vancouver and the Portland area in recent years. Though the company wouldn’t disclose the contract’s worth, the bridge is a 3 million pound prize in a feast or famine industry.“If you wanted to look down at the numbers, it’s something like 120,000 man hours of work,” said Tom Hickman, a company executive.The United States lost 5.7 million manufacturing jobs from 2000 to 2010, according to the Wall Street Journal. Jobs have ticked up in recent years, but still fall short of the pre-recession levels and its peak in the 1970s.