Hyatt Regency walkway collapse: America's most devastating engineering disaster

On 17th July 1981, a tea dance attracted hundreds of partygoers to the Hyatt Regency Hotel in Kansas City. A high school reunion was also taking place in the hotel.

This Hyatt Regency had been opened just over a year earlier. Some of its most distinctive features were its large, airy atrium and the three skybridges that crossed over it. They were attached to the roof of the building rather than being supported by columns. These skybridges, or walkways, were at the second, third, and fourth floor levels.

In that same atrium, at about 7pm, over 1,500 people – accounts of the exact number differ – were having fun dancing or watching others dancing from the skybridges.

Then, without warning, two of the walkways began swaying. In moments, they collapsed and fell to the floor, crushing and trapping hundreds of the dancers beneath them.

To rescue so many people under so much concrete was an immense task. But what made it even worse was that the damaged sprinkler system was pouring water onto the disaster area from above. The collapse had also damaged electrical wiring in the building, and the power supply was then cut to prevent the electrical problems worsening the disaster. In short, rescuers were working in water and without light.

The response to the disaster was swift. The first paramedics arrived at just 7:08pm. Yet the challenge was so immense that rescue efforts were still ongoing 12 hours later.

The doors of the hotel had to be broken to let the water pour out. Helpers and victims struggled to communicate by calling out to one another in the dark. Understandably, many reports described the scene as helplessly chaotic.

As well as providing medical aid to the injured, rescuers had to find ways to get people out from under the heavy debris that was trapping them. Construction workers nearby brought their equipment to help. Some people crushed under rubble could only be freed by amputating their limbs. The site was like a war zone.

In the end, 114 people died, while more than 200 were injured.

Needless to say, there was an urgent desire to know – what had caused this tragedy? One significant point was that the second- and fourth-floor walkways had collapsed. However, the third-floor walkway was fine.

The problem lay in the way that the second- and fourth-floor walkways were attached to one another and to the ceiling. The third-floor walkway was not attached to any other walkway, only to the ceiling.

Investigators found that a seemingly small detail of the engineering plans had changed between the design and the construction of the hotel.

The second- and fourth-floor walkways of the hotel were aligned with the fourth-floor walkway directly above the second-floor one. Originally, they were both meant to hang from the ceiling on continuous metal rods. That way, the roof structure would support the weight of both walkways.

However, the design was changed so that one rod attached the fourth-floor walkway to the roof, and another rod attached the second-floor walkway to the support beams of the fourth-floor skybridge.

This meant that the fourth-floor walkway’s beams, not the ceiling, had to bear the weight of the second-floor walkway.

The disaster occurred when the beams of the fourth-floor walkway simply failed under this weight. Thus, both walkways fell to the atrium below.

In fact, it was also discovered that there had been structural issues even during the hotel’s construction. The roof had collapsed and had to be rebuilt before the building was opened.

The Hyatt Regency walkway disaster has become a case study for engineers in how dangerous errors can occur between designs and construction.

There were failures in communication between the engineering company that designed the hotel’s structure and the company constructing it. An even more serious error was that both the engineering company and the construction company failed to take proper responsibility for ensuring that the structure would be safe.

The structural engineering company allowed the construction company to make decisions about the structure and never performed a proper analysis to check these decisions were wise. Nor did the construction company. It seemed that both of them left accountability to the other one, meaning that in the end no-one took responsibility.

Even the Kansas City Division of Public Works Department did not properly check the plans for safety. The original plans – not the altered ones – still should not have been approved.

However, investigators concluded that the engineering company was ultimately most responsible for ensuring that the plans used were appropriate. It lost its licence and the hotel owner paid over $140 million in damages after civil lawsuits.

The official Bureau of National Standards report, published in 1982, described the disaster as 'the most devastating structural collapse ever to take place in the United States'.

Two local newspapers won Pulitzer Prizes for their coverage of the tragedy and its aftermath. The hotel building is still standing, although it is now called the Sheraton Kansas City Hotel at Crown Center.

To learn more about a similar disastrous event, read about how a hotel in South Korea caught fire during a party in 1974. Or for another deep dive into infrastructure, see our list of 8 of the worst bridge collapses in history.