The Big Dig ceiling collapse occurred on July 10, 2006, when a concrete ceiling panel and debris weighing 26 short tons (24,000 kg) and measuring 20 by 40 feet (6.1 by 12.2 m) fell in Boston's Fort Point Channel Tunnel (which connects to the Ted Williams Tunnel). The panel fell on a car traveling on the two-lane ramp connecting northbound I-93 to eastbound I-90 in South Boston, killing a passenger and injuring the driver. Investigation and repair of the collapse caused a section of the Big Dig project to be closed for almost a full year, causing chronic traffic backups.