PLYMOUTH — Unionized employees of the New Hampshire Electric Cooperative on Friday ratified a new contract, averting a looming strike at the utility that serves some 83,000 homes and businesses in all parts of the state.

The vote at NHEC headquarters came after months of negotiations between the utility and IBEW Local 1837 over wages and pensions. The deadlock continued after the previous contract expired on Sept. 30. Both sides agreed to a federal mediator's request for a one-week extension, and negotiations went down to the wire on Thursday.

The 85 IBEW members are primarily line workers, warehouse employees, technicians and control center operators, comprising about half the work force for the utility.

IBEW Assistant Business Manager Tom Ryan said the new agreement provides wage increases and preserves a defined benefit pension plan for new and existing employees, in a modified form with smaller payouts. Wage increases will average 2 percent to 2.5 percent per year over the 5 1/2 years of the contract, he said.

Ryan said the pension plan changes and raises were “reflective of the times.” He declined to reveal the vote totals, but said, “It was a very close vote. I can tell you that.”

The agreement still needs the approval of the NHEC board of directors, which will be meeting on Monday. “NHEC management will be recommending approval of the new contact by the 11-member board,” said Seth Wheeler, communications administrator for the utility.

The protracted negotiations left bitter feelings. “While I'm pleased that we were able to reach agreement with the co-op on a new contract, I'm disappointed that the company chose to paint our union members as greedy and uncaring about their customers,” said IBEW Business Manager Dick Rogers in a press release.

He accused the company of issuing what he called “deliberately misleading statements” about employee concessions made in 2009.

“While it is true that union members weren't forced to accept the same pension cuts as NHEC's non-union employees, IBEW voluntarily agreed to major concessions at that time, accepting 20 unpaid furlough days and significant layoffs,” Rogers said. “The company's willful deception left IBEW members hurt and angry in the days leading up to the vote.”

Wheeler declined to comment on the statement, saying, “We're moving on.”

“This was a long and sometimes difficult process,” said NHEC President and CEO Fred Anderson. “But I'd like to express my thanks and appreciation to the members of Local 1837.”

dsolomon@unionleader.com