A nearly $110 million mixed-use project on Thompson’s Point continues to evolve, nearly three years after it was first introduced.

The Thompson’s Point Development Co., doing business as the Forefront Partners I LLP, will hold a work session with city planners Tuesday to present its new master plan for redeveloping roughly 30 acres of former industrial land off Congress Street near Interstate 295 into a business, arts, sports and transportation complex.

The project, first unveiled in 2011, received its site plan and subdivision approvals before Portland established its citywide master planning process. Thompson Point developers have now designed a master plan covering the entire project, and will submit site plans for individual buildings for Planning Board approval as the project proceeds. Building the entire development is expected to take six to 10 years.

With the master plan, “both sides get a little more assurance about what (the project) is going to be,” said Jeff Levine, the city’s planning and urban development director. “It’s an exciting project. Like all big projects, it continues to change and evolve over time.”

The new plan calls for up to 120 residential condominiums, additional building space, a wider variety of uses and an increase in traffic. It also calls for renovating and re-using four existing buildings, some of which had served the railroad, that had been originally slated for demolition.

A former train shed originally used at Union Station, which was demolished in 1960, will be converted into a multi-use building that will open on an outdoor amphitheater.

City Planner Nelle Donaldson said the master plan represents a “re-envisioning” of the Thompson’s Point development plan.

The original plans were introduced in 2011 and approved on June 5, 2012, after the City Council approved giving the developer a $32 million tax break over 30 years. The new plans show an increase in building area from 600,000 square feet to 641,500 square feet, not counting parking areas.

Last summer, the developers bought a piece of city-owned land on Riverside Street so Suburban Propane could relocate off the point, freeing up 2.5 acres of land for a 45,000-square-foot arena for the Maine Red Claws and a 730-vehicle parking garage.

Developers also purchased a small strip of land to the north of the point from the New England Passenger Rail Authority, and freed up more land for residential condominiums near what will be a hub for rail, bus, marine, and road connections at the site of the existing Portland Transportation Center.

The land acquisitions – a little more than 2.5 acres – allow for the sports arena, hotel, restaurants, office buildings, a sports medicine lab and parking garage to more easily fit on the site.

“This development program, by incorporating a more diverse mix of uses, including residential, advances the concept of this site as a transit-oriented development,” Donaldson wrote in a Jan. 23 memo to the Planning Board.

Chris Thompson, a principal of the Forefront Partners, did not return a call for comment Monday.

The developer has also laid out a new construction schedule for the project, which has two major phases. As proposed, the first phase calls for 14 individual construction projects to be built in eight stages.

The first project is the conversion of an existing brick building into office, cafe and retail space, followed by a multipurpose live theater space to be installed in the existing 14,000-square-foot structure at the end of the point.

Also planned in phase one is what the developers say is the nation’s first accredited circus school – Circus Conservatory of America – followed by a waterfront restaurant, a gym and medical office, an outdoor stage, trail, hotel/condominiums and a restaurant. Construction on the circus school could begin soon.

The event center, office building and parking structures are planned for late in phase one, with a cultural center, office, condominiums and a restaurant planned for the second phase.

In December, developers applied for a building permit to renovate one of two existing brick buildings on the site. Planning documents indicate the building, the closest of the two to Interstate 295, will contain office and retail space and a restaurant. The permit application is still being reviewed by city staff.

Developers are also working on an 18-month project to relocate Suburban Propane so an event center/arena and parking garage can be built next to the rail lines used by the Amtrak Downeaster passenger train. Plans call for a skywalk over the train tracks to a new Portland Transportation Center, also a hub for the Concord Coach Lines bus.

Off-site road and sidewalk improvements leading to the development, mostly funded through a $1.5 million grant from the U.S. Economic Development Administration, are due to begin in March, according to Donaldson’s memo to the Planning Board. The work will enhance bicycle and pedestrian access, as well as automobile access to Interstate 295 and surrounding city streets.

Randy Billings can be contacted at 791-6346 or at:

rbillings@pressherald.com

Twitter: @randybillings