PORTLAND  — Officials developing a report about the future of three bridges between Kittery, Maine, and Portsmouth, N.H., say the long-term costs of construction, rehabilitation and maintenance could reach $620 million over 30 years.

Some of those costs could be offset with toll revenue collected in both states.

The members of the Bi-State Funding Task Force met Tuesday in Portland.

The task force has until mid-December to come up with a final report, which will be presented to the governors of both states.

The current plans call for the rehabilitation rather than replacement of the Sarah Mildred Long Bridge.

The Memorial Bridge would be replaced.

The Portsmouth Herald says the task force also talked about finding ways to reduce costs with savings in personnel and technology.