Keeping one lane of the Longport bridge open during reconstruction work will add a substantial amount to the final price tag, county officials said Tuesday.

While the original estimate for the work at the JFK Bridge between Longport and the Seaview Harbor section of Egg Harbor Township was about $3.1 million to $3.5 million, the contract awarded to Driscoll Construction at Tuesday's Atlantic County freeholder meeting was for just more than $4.8 million.

The added cost is mostly due to bulkhead work that was originally planned for the project's second phase, Atlantic County engineer Joseph D'Abundo said, as well as the cost "due to the extended time of the project and traffic control" to keep at least one lane open.

Flagmen will have to be used to aid traffic because of the bridge's vertical and horizontal curves which allow limited visibility to see traffic coming through, officials said in February.

The possibility both lanes would be shut down during work hours brought dozens of local residents to a freeholder meeting in Longport in February, where many worried about having to take a 18.5-mile detour through Ventnor, Route 40 and Shore Road or a 12-mile detour on the Downbeach Express toll road from Margate to Northfield.

An informal vote at the meeting was overwhelmingly in favor of the alternate-lane plan, including several mayors, police and fire chiefs.

The freeholders decided to go forward with a plan that would keep one alternating lane open during work from Labor Day 2013 to Memorial Day 2014, with both lanes open during the summer seasons.

"We're going to stop work on weekends, as was requested, and at nights it will be curtailed," Atlantic County Executive Dennis Levinson said. "The lanes are open with alternating traffic, and that's going to make it cost more. ... It's got to get done. It couldn't remain the way it was, and we don't want a tragedy with the bridge."

The project will be funded entirely through the state Department of Transportation, D'Abundo said, using the $1 million received annually through a special fund that designates $25 million per year for the maintenance of bridges and the balance from the state transportation fund.

Depending on when the project gets approval from the state, work should begin in mid- to late July, D'Abundo said.

"No work will be done in such a way during the summer months to impede traffic on the bridge," D'Abundo said.

Longport Commissioner Jim Leeds said that "for people coming in and out of Longport, certainly you need to be conscious of getting in and out of town. I understand the requirements of fixing the bridge, but you also have to look at the impact of people living here."

As to the added cost, "I understand everything costs money, but you can go ahead and do something and not be realistic about what it's going to do," Leeds said. "Then when it becomes realistic, it's 'Oh, this costs more money.' …When you get down to doing work, it costs a lot more."

The 50-year-old span, which is made up of reinforced concrete, steel girders and I-beams, will be given new deck joints and receive repairs to the concrete deck, the structural steel in the main span and the steel and timber piles. The capacity of the pre-stressed I-beams will be restored using carbon fiber wrap.

Contact Steven Lemongello:

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