The week in business Email to a Friend DEVELOPMENT Plans for Seaport District tower include âgreat hall,â public access Boston Global Investors plans to break ground at the end of the year on a 17-story tower at 401 Congress St. in the Seaport District, a parking lot tucked between the Seaport Hotel and the Boston Convention & and Exhibition Center. The upper floors will be the kind of state-of-the-art lab and office space that companies flocking to the Seaport have come to expect. The buildingâs base will feature a two-story âgreat hallâ connecting Congress Street and the elevated World Trade Center Avenue. It would be open to the public 24/7 and be located alongside new parks and plazas above the tangle of the Massachusetts Turnpike offramps below. It would be one of the grander and most public ground floors in the Seaport, and thatâs by design, said Victor Vizgaitis, a principal at Sasaki, BGIâs architect on the building. It has set up the lobby to feel inviting, with 40-foot glass arches to let in light, in the hopes that it will serve as a friendly connector for pedestrians crossing the sometimes foreboding neighborhood. John Hynes IV, whoâs leading the project for BGI, said the original investors pulled out during summer, as the COVID-19 pandemic rattled markets and confidence in the viability of building downtown towers. BGI rethought the upper floors, devoting about half the planned office space to lab space instead. But the modification didnât change the buildingâs outward appearance, or its ground floor. Hynes said itâs close to signing a new financial backer for the roughly $500 million project and aims to start construction in late 2021 or early 2022. â TIM LOGAN