PORTLAND — The city of Portland underestimated how much it would cost to resurface sections of St. John Street and Park Avenue, an oversight at least one city councilor said could delay other street improvement projects.

Councilors voted 9-0 this week to pay an additional $412,000 for its local share of the state-funded project.

But they also instructed City Manager Mark Rees to come up with a plan for funding the cost overrun – possibly through the use of city surplus funds – that would avoid having to postpone other street improvement projects.

“I want to know what streets are not going to get done as a result of this,” Councilor Cheryl Leeman said. “It could affect all of us here (on the council), who have made promises to residents that their streets are going to get done.”

Earlier this year, the Maine Department of Transportation announced it was going to repave St. John Street and Park Avenue, better define crosswalks, and reduce travel lanes on the roads that carry thousands of cars past the Portland Expo and Hadlock Field.

The $810,000 project also required the city to provide a local share, amounting to $134,000. The project began after Labor Day. The added cost will raise the city’s share to more than $546,000.

Mike Bobinsky, Portland’s Director of Public Services, told the City Council that after the roads were torn up the city found severe levels of pavement deterioration and in need of more pavement than was originally planned.

“I share the council’s concerns about the price increase,” Bobinsky said. “But we need to make sure we are getting a good project out of this.”