Co-op City Co-op City Celebrates Christmas Tree Lighting By Robert Wirsing Posted on December 21, 2016 Photo by Walter Pofeldt Sign up for our Bronx Times email newsletter to get news, updates, and local insights delivered straight to your inbox! The Riverbay Corporation celebrated its annual Co-op City Christmas Tree Lighting on Wednesday, December 7 at Dreiser Auditorium B. Children and their familie met with the always jolly Santa Claus prior to the holiday.