The LIRR planned a maintenance facility in the yard as part of the East Side Access project. The building was completed in either December 2004 or June 2005. The $80.4 million facility was built using a mix of federal and non-federal funds. The LIRR had built the Arch Street Facility in advance so it could test its then-new M7 cars. When the MTA planned the facility in 2002, it had anticipated that East Side Access would open in 2011 and that the Arch Street Shop could be used to maintain the LIRR fleet. It was thought that the Hillside Facility would not be able to maintain the expanded LIRR fleet on its own. However, after the East Side Access project was repeatedly delayed, the Arch Street Facility was ultimately leased and licensed for other uses.