A major private-public investment partnership will back the $1.4B transformation of the Bunker Hill Public Housing Development in Charlestown.

Private developers, led by the real estate family office of private equity billionaire David Rubenstein, Declaration Partners Real Estate, will work with the Boston Housing Authority to create 2,699 residential units, of which 37% will be income-restricted, the partners announced Monday. Phase 1, the $180M construction of two new buildings delivering 358 mixed-income units, is expected to commence this winter.

Declaration is joining two local developers on the project: the Joseph J. Corcoran Co. and Leggat McCall Properties are also working with the nonprofit Charlestown Resident Alliance on the plan, introduced to the city in 2016. The 15 new buildings will replace 1,000 of the 1,100 units in the existing 42 buildings, the largest public housing project in New England.

Ten of the nearly 2,700 new units will be affordable to families making 60% or less of the area's median income. The residents who live in the soon-to-be-razed buildings are being moved to other properties in the BHA portfolio.

“With the BHA and our developer partner, the Charlestown Resident Alliance has worked to ensure that through robust resident participation, our Bunker Hill redevelopment will become a national model for a truly inclusive mixed-income community,” CRA President Nancy Martinez said in a statement.

Terms of the investment agreement were not disclosed. Boston is investing $120M into the site, the first time the city has used bond dollars to invest into a BHA redevelopment, according to the announcement.

“We are attracted to the social benefits of preserving affordable housing while adding market rate housing in Boston, which we intend to continue to invest in over the long-term given the City’s diverse economy and strong demand fundamentals,” Declaration Partners co-founder Todd Rich said in a statement.

The project, expected to take 10 years, will deliver 1,689 market-rate homes and 7 acres of open space, along with 50K SF of retail and a 14K SF community theater. A fifth of the retail space will be made available to local retailers for 50% of triple net market-rate rent, according to the master plan. Developers of the Stantec-designed plan said it will meet Passive House and LEED Gold certification and preserve 500 existing trees, a point of contention among residents earlier this year.