The Deadliest Structure Collapses of All Time

During a period of heavy rains, a passenger train traveling near Pueblo, Colorado, slowed its pace in case of washaways. Unfortunately, a flash flood barrelled down an arroyo, a dry creek, just as the train crossed a trestle bridge. The massive wave knocked out part of the bridge and sent four train cars into the floodwaters, killing 111 people – most of whom drowned. The arroyo was dry again within hours.

During a summer evening “tea dance” party at the Kansas City Hyatt, a raised walkway full of partygoers collapsed, falling onto the walkway below it, which then collapsed onto the lobby dance floor. The catastrophe, which killed 114 people and injured another 216, was caused by poor construction oversight and a last-minute change to the walkways’ steel rod anchor design.

During a 6.3 magnitude earthquake that struck the city of Christchurch, a building housing a TV station, a clinic, and a language school collapsed, killing 115 people – most of them international students at the language school. It was later determined that fundamental design errors led to the collapse, and that the construction design should never have been approved. In addition, the building’s construction manager had faked his engineering degree.

On Sept. 14, 2014, a guesthouse collapsed at the Synagogue Church of All Nations, a Christian mega-church run by the late televangelist T.B. Joshua. Most of the 115 people who died in the disaster were South African. Government investigations revealed that the building did not have a valid permit and that structural failures, including inadequate beams, caused the collapse.

After a 6.4 magnitude earthquake struck southern Taiwan during Lunar New Year celebrations, a 17-story residential building collapsed, trapping hundreds of people in the rubble and causing 116 deaths. Subsequent investigations found cooking oil cans were used as filler in the wall caibites, and that polystyrene (styrofoam-like product) was mixed in the concrete for the support beams.

Four days after a federal mine inspector declared a coal slurry impoundment dam near Buffalo Creek satisfactory, the dam burst. Heavy rains contributed to 132 million gallons of coal refuse wastewater spilling over two subsequent dams and overwhelming 16 coal towns along the creek. About 4,000 people lost their homes, over 1,000 were injured, and 125 were killed.

A six-story hotel in Nakhon Ratchasima collapsed in less than 10 seconds after a support column failure. Multiple conferences and meetings were taking place in the building at the time, contributing to 137 deaths and 227 injuries. Six people, including the building owner, were arrested after the disaster, which was caused in part by an unpermitted building addition that added multiple floors without proper reinforcement of the original foundation.

The Pemberton Mill was a five-story textile mill that was crammed with more equipment than it could hold as its owners attempted to increase profits. This proved disastrous as the mill collapsed with 800 workers inside, many of them young immigrant women. Rescue efforts lasted into the evening, when another disaster struck. An oil lamp carried by a rescue worker broke, which set the ruins ablaze, killing the remaining workers who were still trapped inside.

After heavy rains, the river under the Maddur railway bridge was dangerously engorged. As a loaded train crossed the bridge, it collapsed, sending five railcars into the river. The carriages sank and an estimated 150 people drowned. The bridge was subsequently rebuilt and remains in use.

Known as the Tangiwai Disaster, the collapse of the Whangaehu River Rail Bridge occurred just before a passenger train began to cross, sending the engine and six railcars into the river and killing 151 people. The bridge collapse was caused by a lahar (rapid mudflow) that broke through a nearby dam holding back Mount Ruapehu’s Crater Lake.

The target of the Oklahoma City bombing, the federal building collapsed after one structural column gave way. A third of the structure then collapsed – all within seconds of the truck bomb detonating. Over 700 people were injured, and 168 were killed.

The second tallest building in Nepal, Dharahara was a watchtower that stood over 200 feet tall with an internal spiral staircase and an observation deck. During an earthquake with an estimated magnitude of 7.8, the tower completely crumbled, with only its base remaining. Around 200 died in the collapse. The tower has since been rebuilt.

The Fiesta del Dulce Nombre de Jesús (Party of the Sweet Name of Jesus) is an annual celebration in the city of Sincelejo that includes days of bull fighting in a temporary wooden ring called a corraleja. In January 1980, the wooden bleachers of the corraleja collapsed due to poor construction and overcrowding, causing 222 deaths as well as hundreds of injuries.

Completed in 1839, the Angers Bridge was an iron suspension bridge over the Maine River. A combination of heavy winds and oscillations from a battalion of soldiers marching across the bridge caused multiple anchoring cables to snap, leaving one side of the bridge angled toward the water. Although many soldiers were saved from the water, 226 died.

Just a day after a newly-built dam was put into use by the filling of a reservoir, the dam broke. An engineer noticed and reported a small crack that day, but by the time action was taken to relieve the pressure, the crack had widened to 30 feet and an avalanche of water rushed through, flooding the Loxley Valley. Over 4,000 homes were flooded, and 244 people were killed.

Two poorly maintained tailings dams above the village of Stava held toxic mud, sand, and wastewater, byproducts of local fluorite mining. A few years after their last active use, the dams collapsed, sending their muddy contents into the valley. The mudflow destroyed eight bridges, 62 buildings, and killed 268 people.

The New London School was built in 1932 with gas heaters. To cut costs, the school board canceled the natural gas contract in 1937 and switched to untreated, odorless residue gas (a byproduct of oil production). However, the new gas line had a leak that eventually filled a crawl space that ran the whole length of the school. When it finally ignited, the massive explosion blew the roof off the building and destroyed the main wing. Around 300 people were killed, most of them fifth through 11th grade students.

This arched stone footbridge across the Meuse River was originally constructed by the Romans in 50 AD. The wooden bridge collapsed in 1275 while a procession of people crossed it, leading to 400 deaths. The bridge was rebuilt slightly to the north five years later, and again in 1948 after it was damaged in World War II.

The 1988 Spitak earthquake in Armenia had a magnitude of 6.8 and killed over 25,000 people as it destroyed homes and industrial buildings. During the quake, the floors of the Dzhrashen Elementary School gave out, as they were improperly attached to the walls. The structural failure led to the deaths of 400 people, mostly children.

The Malpasset arch dam was built into an impermeable rock base and completed in 1954. Due to inadequate surveying of the base, a tectonic fault in the rock was likely overlooked, which led to water seeping under the dam and compromising the structure. Just four years after its construction, the dam cracked during heavy rains and a 130 foot wall of water emerged, destroying two downstream villages and killing 423 people.

The St. Francis Dam was built to hold a reservoir that would provide water to Los Angeles. Just as it was being filled for the first time, the dam collapsed, causing a flood of 12.4 billion gallons of water that killed 431 people. The collapse has been attributed to poor engineering decisions – including raising the planned height of the dam by 20 feet without adjusting the base – and has been called the worst American civil engineering disaster of the 20th century.

Built by a construction firm intent on cutting corners, the Sampoong Department Store was only approved to be a four story office building – not a five story department store with a food court on top. Strain on the building due to rooftop air conditioners, coupled with unapproved modifications to support columns, led to the roof caving in on a busy day. A large section of the building then collapsed into the basement, killing over 500 people and injuring 930 more.

This chariot racing stadium was built in the sixth century B.C. It could hold 250,000 spectators and was in nearly constant use. In 140, an upper seating tier collapsed, possibly as a result of being overloaded with people. The accident caused at least 1,112 deaths, although some sources place the death toll much higher at 13,000.

The eight-story Rana Plaza building in Bangladesh’s capital housed five garment factories as well as several shops, apartments, and a bank. After cracks were discovered in the building, the bank and shops closed immediately. Garment workers, however, were ordered to come in the next day, and the building collapsed during the morning rush hour. After weeks of recovery efforts, 1,134 people were dead and 2,500 were injured.

This wooden beam bridge over the Sumida River was built in 1698, and by 1807 it had fallen into disrepair, with the surrounding villages arguing over who should pay for its maintenance. The bridge collapsed during a festival under the weight of thousands of revelers, and 1,400 of them drowned in the river below.

While the Vajont Dam, one of the tallest dams in the world, was structurally sound upon its completion, the Italian government and the electric company that controlled the dam ignored reports that the basin holding the reservoir was unstable. As the dam was being filled for the first time, a landslide of rock fell into the reservoir, causing an 820 foot wave to breach the top of the dam, flooding multiple villages in the Paive Valley and leading to approximately 2,000 deaths.

This earthwork dam upstream from Johnstown Pennsylvania formed the Lake Conemaugh reservoir. During the summer of 1889, the dam ruptured after days of heavy rains, sending 20 million tons of water barreling through the valley in an event known as the Johnstown Flood. Several towns and railroad bridges were hit before the waters reached and demolished Johnstown. In all, 2,209 people lost their lives in the flood, with 777 never being identified.

The tallest buildings in the world at the time, the Twin Towers of the World Trade Center were hit by commercial airplanes during a terrorist attack on Sept. 11, 2001. The towers collapsed soon after, subsequently causing damage to many nearby buildings. It is likely that fires in the towers contributed to the buckling of perimeter columns and ultimately led to the devastating collapses. Civilian, first responder, and hijacker deaths totaled 2,996.

A pontoon bridge made up of 20 parallel wooden barges, the Ponte das Barcas was in use for three years before disaster struck. During Napoleon’s invasion of Porto, civilians fleeing the town stampeded over the bridge. The weight and movement caused by so many panicked people caused the bridge to collapse, and 4,000 people drowned.

Built cheaply out of wood by a miserly entrepreneur, the amphitheater at Fidenae had no foundation and was constructed on unlevel ground. On its opening day, the stadium reached full capacity as spectators piled in to watch gladiatorial games. Suddenly, the wooden bleachers gave way and the entire stadium collapsed, killing at least 20,000 people and trapping survivors in the rubble for days.