PORTLAND, Maine — A major development project for Portland’s Thompson Point is going to get a 30-year, $31 million tax break from the city.

And the city is planning to use 25 percent of the money it will receive from the development, an estimated $6.6 million, for transit projects.

The City Council voted early Tuesday to approve the tax break for the $100 million project that will include two office buildings, a hotel, an arena and convention center, a concert hall and a parking garage. The tax break drew some opposition at a recent public hearing, but  downtown development and transit officials praised the proposal, to be called The Forefront at Thompson’s Point, saying it would spur  economic development.

The developers say they need the tax break to cover high costs caused by marine clay on the site as well as a costly rail crossing.

The Portland Press Herald says the plan calls for beginning construction early next year.