Pedestrians may now access the Atlantic Street sidewalks under the new bridge. During the 4th of July week, the old bridge, which carries five tracks for Metro-North Railroad and Amtrack trains, was taken down and a new one put in place over the course of roughly 10 days. As portions of the old one were demolished, new pieces — constructed off site in movable portions — were wheeled in and installed, under a method called Accelerated Bridge Construction.
https://www.stamfordadvocate.com/local/article/Atlantic-Street-reopens-as-bridge-repair-complete-14425586.php