As a result of April 2022 flooding, a river burst its banks and destroyed a bridge in Durban, South Africa.
Credit: © Rogan War, Reuters/Alamy Images

Several days of heavy rain have caused severe flooding and mudslides on the east coast of South Africa. A new storm came off the Indian Ocean on Tuesday, April 12th, destroying bridges, roads, houses, and other structures. The storm hit the city of Durban, South Africa’s chief seaport and one of its largest cities, killing at least 443 people. Officials report that 63 people remain missing amidst the damage in the province of KwaZulu-Natal.

The influx of rain is a result of a weather phenomenon called a cut-off low, which occurs when a low-pressure system is disrupted and moves slowly across an area. The storm produced the heaviest rains in South Africa in 60 years and is the deadliest storm on record in the country. Meteorologists estimate that over a month’s worth of rain, nearly 12 inches (30.5 centimeters), fell in one day in Durban.

The downpour of rain caused mudslides that washed away entire hillsides, destroying nearly 600 schools and  60 health facilities. More than 12,000 homes have been damaged from the flooding and mudslides. Some schools were in session during the storm, trapping students and teachers inside. Many people sought higher ground and climbed on top of roofs to stay out of reach of the rushing water and mud.

The flooding also washed out complete roads and bridges. One bridge outside Durban collapsed, leaving people stranded on both sides. The rushing water knocked out all power in the area. The mudslides and damage cut off the supply of clean water. Stacks of shipping containers have collapsed into the water.

Rescue efforts continue to find missing people believed to be underneath houses affected by the mudslides. South African President Cyril Ramaphosa visited with people affected by the disaster and pledged to help rebuild the community.

August 23, 2017

Last week, in the early hours of August 14, heavy rains and flooding caused a massive mudslide on the outskirts of Freetown, the capital city of the small west African nation of Sierra Leone. The mudslide buried parts of Regent, a settlement perched on the slopes of Mount Sugar Loaf overlooking Freetown. The mudslide destroyed or severely damaged hundreds of homes and other buildings and killed 499 people. The death toll is certain to rise, however, as some 600 people remain missing. Rescue efforts continue a week after the disaster, but there is little hope of finding anyone alive in the mud and destruction.

Wreckage is removed from the Freetown suburb of Regent in the days after a mudslide devastated the Sierra Leone hillside community on Aug. 14, 2017. Credit: © Stringer/Anadolu Agency/Getty Images

The population of Freetown and its outskirts has increased sharply in recent years, and makeshift shantytowns have sprung up in Regent and other areas. As land is cleared for homes, however, the deforestation weakens the soil—particularly on the slopes of Sugar Loaf—greatly increasing the risk of land- and mudslides. Environmental groups have planted many trees, trying to replenish parts of the forest, but they can not keep up with the pace of clearing and unregulated development. Climate change, too, is adding to the problem, as more severe and erratic weather patterns bring unusually heavy rains. This summer has been exceptionally wet in and around Freetown, and floodwaters further destabilized the Sugar Loaf hillsides. Torrential downpours saturated the area in the days preceding the mudslide.

The port city of Freetown, the capital of Sierra Leone, sits between hills and the Atlantic Ocean. Credit: © Shutterstock

Entire parts of Regent were buried in the mudslide, which sent mucky waters cascading through other settlements and into the streets of Freetown itself. Some 3,000 people have been left homeless by the disaster, another 10,000 people have been evacuated from areas at risk of further mudslides, and the Sierra Leone government is asking thousands more to leave potentially dangerous areas. Survivors face threats from cholera and other waterborne diseases as the many deaths and destruction have tainted the area’s water supplies. International aid is pouring into Freetown, however, providing clean water, food, shelter, and medical supplies.

Further rains have hampered rescue efforts in Regent, and there is a shortage of heavy equipment to dig through and remove the many tons of mud covering homes and streets. The day after the disaster, Sierra Leone President Ernest Bai Koroma declared seven days of mourning as bodies began being retrieved and buried—most of them unidentified—in mass graves at nearby cemeteries. Since then, many survivors have ignored warnings to keep away and returned to the devastation to search for missing family members and retrieve belongings.

On August 16, two days after the disaster in Sierra Leone, a similar mountain mudslide struck the fishing village of Tora on the banks of Lake Albert in the Democratic Republic of the Congo, killing more than 200 people. There, the disaster was also caused by unusually heavy rains and deforestation for the creation of makeshift housing.

December 10, 2015

December saw flooding in several parts of the world, with separate weather events inundating portions of the United Kingdom and Ireland, southeast India, and the United States Pacific Northwest.

A woman collects drinking water at a residential area flooded with rainwater in Chennai, India, on Dec. 6, 2015. Credit: © Arun Sankar K, AP Photo

Early in the month, Storm Desmond set a record for 24-hour rainfall in the United Kingdom, dropping 13.4 inches (341 millimeters) in the northwestern county of Cumbria on December 5. Desmond was a type of large, swirling windstorm called an extratropical cyclone. The storm pushed an atmospheric river—a channel of intense moisture in the air—over the region, causing heavy flooding in parts of northern England, northern Wales, and southern Scotland, as well as central Ireland. The floods damaged thousands of homes and killed two people.

The city of Chennai, in southeast India, received 15.6 inches (397 millimeters) of rain over a two-day period in early December. The drenching followed a record-setting November that produced 47.1 inches (1196 millimeters) of total rainfall. The rains caused flooding throughout the state of Tamil Nadu, causing the deaths of more than 200 people and forcing thousands of others from their homes.

In the United States, both Portland, Oregon, and Seattle, Washington, received a month’s worth of rain over just a few days in early December. Heavy rains led to mudslides, sinkholes, and flooding in the Pacific Northwest, leaving thousands of homes without electric power and killing two people.

Additional World Book articles:

• Heavy Rains Trigger Massive Flooding in Australia – A Behind the Headlines article
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March 26, 2014

The search continued today for victims of the enormous landslide that destroyed much of Oso, Washington, last weekend. The death toll currently stands at 24, but as many as 175 people remain unaccounted for. State officials disclosed yesterday that rescuers have located 8 more bodies but have not been able to extract them from the massive pile of mud and debris. “We haven’t lost hope that there’s a possibility that we could find somebody alive,” local fire chief Travis Hots told reporters last night. However, no one has been pulled out alive from the muck for four days.

On March 22, a giant wall of rain-saturated earth slid off the mountain, burying much of Oso, a hamlet 60 miles (96 kilometers) north of Seattle. The landslide brought down an unimaginable amount of earth–as much as three times the volume as there is concrete in Hoover Dam, according to one engineer’s estimate. After surveying the area from the air, Washington Governor Jay Inslee said the landslide “basically cut a mountain in two” and deposited it on the town below, causing “devastation beyond imagination.” Washington state geologist Dave Norman reported to the media that the landslide left behind a cliff known as a head scarp that is 600 feet (183 meters) high. “This is one of the biggest landslides I’ve seen,” he noted. The mudslide destroyed 49 houses, temporarily dammed a river, and left a square mile wasteland in its wake.

Slides and floods have long threatened Oso and other nearby communities. In 1999, the Army Corps of Engineers specifically warned of “the potential for a large catastrophic failure” in the valley because erosion caused in part by a nearby river could “reduce stability of the entire slide mass.” However, state emergency management officials–declaring that they had done everything possible to reenforce the hillside with retaining walls–attributed Saturday’s landslide to near-record rains on loose glacial soil. The area received 7.14 inches of rain in the first 19 days of March.

Hurricane Jova made landfall today on Mexico’s west coast in the state of Jalisco with maximum sustained winds of 100 miles (160 kilometers) per hour. Government officials warned of coastal flooding and landslides along a 210-mile (340-kilometer) stretch between the resort towns of Manzanillo and Cabo Corrientes. In Manzanillo, the storm prevented ships from sailing into and out of Mexico’s main port of arrival for cargo containers. Some 13 container ships rode out the storm in the city’s harbor.

Manzanillo © Corbis/Alamy

Down the coast, a storm-triggered mudslide swept away a hillside house, killing two people. Two children were injured when the force of the wind and rain caused the walls of their brick house to collapse.

After passing within about 12 miles (20 kilometers) of the resort city of Puerto Vallarta, Jova moved inland and steadily weakened to tropical storm status, according to the U.S. National Hurricane Center.

Additional World Book article:

• National Weather Service