The cost of resurfacing Maine’s busiest highway bridge this summer will be almost 50 percent more than the state estimated.

Work on the Piscataqua River Bridge, which connects Kittery and Portsmouth, New Hampshire, is likely to cost $52.6 million, almost $17 million over initial estimates. The bridge on Interstate 95 is Maine’s principal artery for commuters, freight and tourists. About 74,000 vehicles cross the bridge every day, and on busy summer weekends daily traffic balloons to at least 130,000 cars and trucks.

“It is the most critical bridge in the state,” said Nina Fisher, deputy commissioner for the Maine Department of Transportation.

Unprecedented measures to keep that traffic moving while construction crews resurface the nearly mile-long, six-lane bridge means the project will cost more than anyone expected.

“Basically, we have a traffic movement project with some bridgework thrown in there,” Fisher said.

Resurfacing the 46-year-old bridge will require fixing issues with its concrete deck, installing a new waterproof membrane and repaving. Last year, the Maine Department of Transportation estimated the project would cost $36 million and take about three years.

Maine’s transportation department shares the cost of the bridgework with the New Hampshire Department of Transportation. The Maine Turnpike Authority will also pay a portion for work on its property north of the bridge.

At the time the request for bids was put together, the plan was to keep the travel lanes on the bridge open during busy summer months and close one lane of traffic in either direction during other times of the year.

But even that would result in gridlock, according to a Maine Department of Transportation analysis.

“Analysis using the most recent record-breaking interstate traffic volume data led to more complex contract requirements for times when contractors can close lanes to perform the work,” said an undated Maine DOT memo. “Actual lane closure tests on the bridge have demonstrated that unacceptable backups will result if three lanes of travel in one direction are not available for traffic at more and more time periods throughout the year.”

The need to keep more lanes open means the winning bidder will have to figure out a way to get the work done when they can. That might mean adding crews, working longer hours and working overnight, Fisher said. All those costs would have been included in the bid contractors submitted, she said.

The project also cost more than initially thought because work was added including paving and barrier improvements on Maine Turnpike Authority property and roadside work so the bridge shoulder and approaches can be used as another travel lane during peak periods.

Even with added costs, traffic snags and backups will be unavoidable, but “the contract has been structured to keep people and goods moving as much as practical,” according to the department. There are many times when all three travel lanes will be open each way, but during off-peak times, the contractor may still have to narrow them to two lanes, Fisher said.

The department expects to deploy advance warning message signs, more state police and service patrols, travel time notifications and public information announcements to keep traffic moving, she said.

The Maine Turnpike Authority board of directors, in a meeting Thursday, conditionally approved its $9.2 million share of the project. The Maine DOT is leading the development, but can’t make a contract award until it gets approval from New Hampshire.

High bids on the project “obviously” raised some eyebrows at the New Hampshire Department of Transportation, but given the bridge’s strategic importance, it will likely get approval from the state’s Executive Council next month, said department spokesman Bill Boynton.

SPS New England, a construction company from Salisbury, Massachusetts, put in the lowest bid for the project, almost $52.6 million. Pittsfield-based Cianbro Corp. bid $53.4 million for the work, and Reed and Reed Inc., from Woolwich, put in a nearly $65 million bid.

Peter McGuire can be contacted at 791-6325 or at:

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