LAWRENCE — The vacant Van Brodie textile mill, which has stood near the Methuen city line for nearly a century, will soon be productive again.

It won't be manufacturing fabric, but the building will take on new life with 102 apartments. Trinity Financial, a Boston developer, is investing $48 million in renovating the structure.

"I think it's going to be a good use," Mayor Daniel Rivera said. "We know we have a housing need."

The homes will be "mixed income," with some being rented at affordable rates and others available at market rents, according to Dan Drazen, project manager for Trinity.

The developer has also pledged to buy and renovate three triple-deckers in Lawrence, Drazen said. Trinity has already purchased two three-family houses, one at 80-82 Inman St., the other at 17-19 Eutaw St.

These properties are vacant and "not in the best of shape," Drazen said.

Rivera asked Trinity to invest in the three-family houses, he said.

"It is an unusual request," Drazen said, but his company went along with it.

Rivera said he asked Trinity to buy the triple-deckers because he wants to "bring back the neighborhoods."

The mayor also said he prefers putting businesses into the old mill buildings – but converting an industrial structure into homes is better than letting the property remain vacant, he added.

"We think this is going to help the rental problem," he said of the Van Brodie project.

The bulk of the financing for the project will come from low-income housing credits from the state Department of Housing and Community Development and historic tax credits from the state and federal governments, Drazen said. The low-income housing credits have yet to be approved.

State affordable housing programs and the city are also putting money into the undertaking, he said.

The federal government has approved Trinity's request for a historic tax credit but the state has not yet acted upon the developer's bid for a similar provision, he said.

The Van Brodie property is at the rear of what used to be the Arlington Mill and faces Stevens Pond.

Drazen said Trinity Financial, which has been in business for 30 years, has a passion for revitalizing older cities.

"This is something our firm loves," he said.

Asked if Trinity will hire Lawrence residents to work on the project, Drazen said, "Trinity has a policy of doing our best to hire local people."

Rivera said he will "encourage" the developer to stage a job fair so local people will have a chance to apply for jobs on the project.

Trinity does not need the approval of any city boards, according to Rivera.

"They're good to go," he said.

This story has been edited to correct some details.