The reason why floods can be so dangerous is that sometimes they happen fast. Flash floods are when waters rise in a matter of minutes. This means that people in the flood’s path do not have much time to get information about where to go or what to do. Even if it doesn’t happen in minutes, it can still be unexpected. For example, a mountain stream that is normally a few inches deep can turn into a 10-foot-deep river in less than an hour in the right weather conditions.
What Is the Deadliest Flood Ever?
Several of the deadliest floods in recorded history have occurred in China. In that country, there are several rivers with large populations that live close by. However, anywhere there is a river there is the possibility for a deadly flood.
1. 1931 China Floods
This set of floods is also referred to as the 1931 Yangtse-Huai River Floods. After a drought from 1928-1930, the area of the Yangtse and Huai rivers received a lot of snowfall. When it started to melt in early 1931, the extra water flowed down the river, along with still melting ice and snow. Then, heavy continual rains for months caused the rivers to rise even more. Starting in June, people living in low lying areas had to evacuate due to flooding. Then in July, 9 cyclone storms, similar to hurricanes, hit the region, adding more downpours to the situation. The area received 2 feet of rain in one month. This caused flooding the size of the country of England (approximately 69,000 square miles.) It severely affected 8 different provinces and had more moderate effects in many others. Overall, 150,000 people died as a direct result of drowning in the floods. However, an additional 2 million people reportedly died as a result of not being able to get food or other life necessities. The flood also caused a cholera outbreak the following year. This is a bacterial illness caused by drinking dirty water, which people in the affected area were likely doing since they lacked access to resources. Up to 100,000 additional deaths were caused by this outbreak. Some estimates put the total number of deaths from this months-long flood at nearly 4 million. The flood waters started to recede in August, however, due to more fall rains, some of the area’s rivers did not go back to normal until November of 1931. Between 25 and 50 million people were affected by the flooding. About 15% of the area’s important wheat and rice fields were destroyed.
2. 1887 Yellow River Flood
Over 900,000 people were killed in the 1887 flood on the Yellow River in China. Part of what made this flood worse was the fact that Chinese farmers would build dikes along the river to protect their crops. This caused the overall level of the river to rise because it could not deposit silt during usual smaller floods. This flood affected over 50,000 square miles. Two million people lost their homes. It is estimated that an additional 900,000 people died after the floods due to a lack of access to food, clean water, and healthcare. Overall, experts estimate that at least 3 million people died from this flood.
3. 1938 Yellow River Flood
In 1938, the Chinese military opened up levees on the Yellow River to prevent the advancement of the Japanese army, which had taken control of Northern China. It is not known exactly how many, but many Japanese soldiers died in the flooding. However, it also affected the local communities. It is estimated that 800,000-900,000 people died in total, however, that number is not certain. In the war-torn villages, many government officials had already left, so official counts were not always done. The surrounding area was deeply affected for several years following the flooding. The fields were covered in silt so they were not as fertile. A lot of structures were destroyed. This is considered one of the most significant acts of environmental warfare to ever occur. The river was not returned to its earlier course until 1947.
4. 1975 Banqiao Dam Failure
During Typhoon Nina, a category 3 storm, over a year’s worth of rainfall (about 3.5 feet) for the area fell in just one day on August 7, 1975. The damn had been built to withstand a “one in a thousand-year” rainfall event of about 1 foot. Due to the dam breaking, the People’s Liberation Army purposely had to destroy other dams further downstream to control the flooding. Even so, dikes on the Quan River failed. The resulting flooding caused anywhere from 85,000-240,000 deaths. Entire towns, like the Daowencheng Commune, were entirely wiped out. Due to the technology of the time and the weather conditions, warnings were not received or were misunderstood. Many people in the area did not have a telephone at this time so signals were attempted via telegraph and flares. People acting as messengers to take the warning to towns in person often got caught up in the floods. The Chinese government lists the official death toll as 26,000. They also initially covered up this event. For over 12 years, no one outside of China knew about what happened. They did not allow the media to make any reports. However, in 1987, a Chinese journalist wrote a book about the floods. In 1995, the Henan Daily, the newspaper for the area where the floods took place, published a story about what happened. Finally, in 2005, the government declassified the official documents relating to the dam failure.
5. 1935 Yangtse Flood
This event followed just a few years after the devastating 1931 floods in the region. Much of the infrastructure that had been rebuilt was damaged once again. And a lot of the measures that had been put in place to reduce flood risks were overcome. That year, there were a high number of typhoons off the coast of China. This may have created a sudden rise in the river levels on July 6, 1935. Several levees broke, and other areas became flooded when the river spilled over its banks. Over 140,000 people died as a result of the flood. Even more died afterward from starvation. The previous year had been a drought, which meant there were fewer crops than usual. This flood affected over 5500 square miles of farmlands, further reducing the available food in the area. Others died from diseases that spread as a result of the flooding.
6. 1530 St. Felix’s Flood
Just so I don’t single out China too much, let’s also talk about the 6th deadliest flood in the world. This flood happened on November 5, 1530 in The Netherlands. It was named for that day’s name day, St. Felix. Another name for this flood is Evil Saturday or Bad Saturday. Estimates put the number of dead at 100,000. It happened in the Dutch Province of Zeeland. Part of the area was reclaimed by the sea and could not be recovered. In 1532, another flood occurred in the area, destroying the recovery efforts from this 1530 flood. Because it happened so long ago, there aren’t quite as many details available about this flood, but we do know it was devastating and deadly.
Learn More About Floods and Severe Weather…
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The 1931 Yangtse-Huai River Floods in China were the deadliest floods ever. As many as 4 million people died. What causes floods? Heavy rains, large amounts of snow melt, large ocean waves, and breaking levees and dams are common causes of flooding. What is the 2nd deadliest flood ever? Over 900,000 people were killed in the 1887 flood on the Yellow River in China.
