The MBTA Fiscal and Management Control Board today approved the ground lease at Mattapan Station to the partnership of Nuestra Comunidad Development Corporation and the Preservation of Affordable Housing Inc. (POAH). Nuestra and POAH will be developing a mixed-used project, including affordable housing and commercial space, in the long-underutilized River Street parking lot next to the station.

The transit-oriented development is projected to include 135 units of housing, 69 of which are described as affordable, and 12,000 square feet of commercial space. Given its proximity to transit junctions, the site must include 50 parking spaces reserved for commuters.

Mark Boyle, assistant general manager of real estate and asset development at the MBTA, briefed the press and public on two long-term leases considered by the board Monday. Along with the Mattapan lease, the board approved a lease of surplus land at Beverly Depot.

“It transforms a parking lot that isn't generating us much revenue and is costing us from a maintenance perspective, to a more productive use,” Boyle said of the Mattapan project.

Two proposals were considered for the lot, “which you can see on an average daily basis sits quite empty,” Boyle said. Trinity Financial Inc. backed the only other offer for the lot, proposing a mixed-used development with 267 units of housing and 8,000 square feet of commercial space.

POAH/Nuestra will pay for the first 20 years of the 99-year lease. Those 20 years will bring the total revenue generated to an expected $4,885,970, the agreed-upon price point for the lot.

MassDOT is obligated to accept the highest reasonable offer for the site, resulting in POAH/Nuestra’s extended lease beating out Trinity’s simple sale for $2 million.

Aside from the financial requirements, city and state officials considered the impacts on area density and traffic.

“There was some concern about the size of the Trinity proposal,” Boyle said, “and the traffic that would be generated by that. So we actually did a consultation with the city and with the [Boston Redevelopment Authority]. We called them and asked them to review both proposals, and they did state their preference was the POAH/Nuestra, although they liked certain aspects of the Trinity proposal.”

Bus routes are not expected to be affected by the development, Boyle said, as they will continue around the lot in much the same manner as they currently do.

“We’re working very closely with our bus operations department to make sure the final site plan does not negatively impact [routes],” he said.

The Mattapan Station lot is located at a nexus of public transit. The Mattapan high-speed trolley, several bus lines, and the soon-to-be-completed section of the Neponset River Greenway converge at the site.

Though the trolley, the future of which has been a subject of some concern, will be maintained for at least the short term, Boyle said the development does not indicate an express commitment to the line’s future.

“It does not make any commitment one way or another,” Boyle said. “It does not speak to that trolley. But one would hope there would be additional ridership with all the folks that would be living in the 135 units, that the expectation is that many of them would be using the trolley.”

Community members were introduced to the development team and the broad plans for the site at a public MBTA meeting in late June. The plan will work its way through the BRA’s Article 80 large project review over the coming year. The proponents— Nuestra and POAH— plan to host a public meeting on Aug. 2 at the Mattapan library at 6 p.m.