Image courtesy of Massport

After approving development of 1,775 units of primarily luxury housing in Boston’s Seaport District, Massport will prioritize affordability for its next project in the neighborhood.

The agency will seek formal proposals from developers next spring for a 0.6-acre parcel on D Street next to its 1,500-space parking garage which opened in 2018. The parcel can accommodate approximately 200 housing units in an 18-story building, according to a request for qualifications issued this week.

The mixed-income development would be the first on Massport-owned land in the neighborhood. Acknowledging the shortage of affordable housing in the Seaport District, Massport said it wants proposals that include a range of income-restricted units for households earning from 30 to 120 percent of the area median income, in the form of condos, apartments or a mix of both types. Market-rate units could be included to subsidize the affordable component.

Developers also will have to show that they have experience with affordable housing, and have completed projects that include at least 40 percent income-restricted units.

In a statement, Massport CEO Lisa Weiland said the agency is responding to calls from Gov. Charlie Baker and Boston Mayor Michelle Wu for affordable housing production.

Life science developers are dominating the competition for parcels in Boston’s urban core, but public agencies have sought to generate housing in surplus property dispositions. Massachusetts Department of Transportation required a minimum 20 percent affordable housing in seeking developers for its parcel 25 property on Kneeland Street.

The 27,000-square-foot Massport property sits above the Ted Williams Tunnel and borders the parking garage, MBTA Silver Line right of way and South Boston Haul Road. Because of structural engineering limits related to the tunnel roof, Massport envisions a mid-rise residential building on the property.

Development on the property, known as parcel D-4, can be expanded by cantilevering the floor plates above the second floor on the north and south sides of the building, Massport said.

The agency also will place a priority on diversity, equity and inclusion of development teams in the selection process. Massport expects to issue a request for proposals next spring and select a developer in late 2022.