On May 11, 1976, an ammonia truck disaster killed 7 Houstonians and injured nearly 200
May 11 marks the 44th anniversary of one of the scariest moments in Houston history, when a semitrailer carrying more than 7,000 gallons of anhydrous ammonia fell from a freeway ramp, spilling its lethal contents.
The incident, which left seven dead and nearly 200 injured, caused officials to rethink how to tackle chemical disasters and led to rules still in use today.
Over forty years later, the route that ammonia truck took still snakes through a city that has doubled in size, leaving Houston vulnerable to a catastrophic accident.
Just after 11 a.m. on May 11, 1976, a tanker truck carrying the dangerous chemical fell onto the Southwest Freeway from the 610 West Loop above. The driver had lost control of the rig and hit a support beam.
The National Transportation Safety Board would later determine that the driver was not traveling at a safe speed. He barely missed landing on a car passing by. Not much was left from the truck in the aftermath.
From a Houston Post dateline: “As the sign says, the weather is fair, it’s 83 degrees and the time is 11:17 a.m. The date is also May 11, and that white cloud in the distance is the toxic blanket of anhydrous ammonia fumes which resulted from a tank truck crash at Southwest Freeway and the West Loop which killed five persons. The Texas Air Control Board took the picture from its offices at 5555 West Loop South.”
More at above LINK.