The Memphis tanker truck disaster was a transportation disaster that occurred on December 23, 1988, when a tractor-trailer tanker truck hauling liquefied propane crashed on an exit ramp at the Interstate 40/Interstate 240 (I-40/I-240) interchange in downtown Memphis, Tennessee. The crash ruptured the tank, causing the leaking gas to ignite, which produced a large explosion that set multiple vehicles and structures on fire. The tank was then propelled from the site where it crashed into a residential complex and started additional fires. The accident resulted in nine deaths and ten injuries. The interchange where the accident occurred was considered unsafe and poorly designed, and had been the site of several previous accidents. It was completely rebuilt in the 2000s.
Background
The accident occurred at the interchange in Midtown Memphis between I-40 and the western terminus of I-240. Approaching this interchange from the west, I-40 travels in an east–west alignment and shifts into a north–south alignment at this interchange. I-240 also meets the interchange from a north–south alignment. The interchange was first constructed in the latter 1960s, and opened to traffic on July 14, 1971. At this time, it was planned as a four-way interchange; I-40 was to continue straight through the interchange in an east–west alignment, and I-240 was to continue north of the interchange on what is now I-40. Many residents opposed the routing east of this interchange because it was slated to pass through Overton Park, and filed a series of lawsuits to stop the interstate's construction. These lawsuits culminated in the 1971 U.S. Supreme Court case Citizens to Preserve Overton Park v. Volpe, and in 1981, the Tennessee Department of Transportation (TDOT) abandoned plans to route I-40 east of this interchange. Instead, the department chose to redesignate the northern loop of I-240 north of this interchange as part of I-40. As a result of these original plans, however, the interchange was constructed as a four-way combination interchange, and contained several unused ramps and bridges intended to carry traffic to and from I-40 east of the interchange. I-40 traffic continuing both through the interchange and exiting onto I-240 was required to use one-lane ramps, some of which contained hazardously sharp curves. The ramp where the accident occurred was a flyover ramp with an advisory speed limit of . At the time of the accident, the entire interchange was considered one of the most dangerous in the state and had a crash rate much higher than the state average. TDOT had begun preliminary work in early 1988 for a project to reconstruct the interchange, estimated to cost $100 million at the time (equivalent to $ in ).