The world's worst dam disaster

Yesterday I blogged about Britain’s worst dam disaster. The world’s worst happened in China in 1975.

As part of his ‘Great Leap Forward’ designed to enable China to become a major industrial power, Chairman Mao encouraged peasants to go off and build dams, which they did with great enthusiasm, but also with a Brexiter-like disdain for experts. So the structures were jerry-built, and within a couple of years, they were collapsing. A hydrologist who tried to sound a warning was purged for being a ‘right-wing opportunist’.

In August 1975, storms dumped heavy rain on Henan province. On 9 August, the Shimantan dam collapsed and half an hour later, the Banqiao dam gave way, unleashing a wall of water 20 feet high. In all 60 dams burst, flooding an area of 4,000 square miles.

China tried to hide the disaster from the world’s gaze, and it was 30 years before the truth began to emerge. The authorities admitted that at least 26,000 had been killed, but other estimates put the figure as high as 85,000 killed by the floods, with another 145,000 from the famine and disease that followed.

For the full story, see my book A Disastrous History of the World.

Britain's worst dam disaster

The people of the Peak District town of Whaley Bridge in Derbyshire are still unable to return to their homes as fears continue that the dam holding back the Toddbrook Reservoir (pictured) above the town may burst, unleashing a devastating flood.

The reservoir was built in 1831. About 20 miles away, the collapse of another dam in 1864 brought Britain’s worst ever dam disaster. As Sheffield became a major centre for steel-making, the Sheffield Waterworks Company decided to build new reservoirs in the surrounding hills to provide the water the booming area demanded.

By 11 March 1864, the first of them, above the village of Bradfield, was almost finished when a local man noticed a crack in the structure. It was a wet, stormy night and water was also coming over the top of the dam. Within hours, the structure had burst, and a mountain of water careered down the valley below.

Bradfield was the first place to be hit, though mercifully most of the inhabitants had been evacuated, but no warning reached Malin Bridge, where more than 100 people were killed, and altogether in the valley, 270 died. For the full story, see my book A Disastrous History of Britain.

Diary Date - flood talk October 9

I'm giving a talk entitled 'Are floods getting worse? at Swiss Cottage Library on October 9 at 1830, based on my book Flood: Nature and Culture.  Admission free.  All welcome.   

Last year, the UK’s Environment Agency issued a record number of flood warnings, while also in the last few years, Pakistan has had its worst monsoon floods in eight decades, Thailand suffered one of the costliest inundations in history, Colombia and Brazil experienced the severest in living memory, and Australia’s prime minister declared the Queensland floods perhaps the worst natural disaster ‘in the history of our nation’.

So are things actually getting worse? I will be revealing that floods are the natural disasters humans are most likely to experience, and that some of the most ambitious structures ever built have been put up to defend us against them.

I will also be telling how stories like that of Noah’s ark, about an apocalyptic flood which almost wipes out humanity, feature in dozens of religions all over the world. Floods caused by rain, melting snow, storms, tsunamis, tides, the failures of dykes or dams, or deliberate act of war all feature.

The talk will also look at the way floods have been portrayed in films, literature and art.

Floods in Africa

Unusually heavy rains in Nigeria have resulted in at least 20 deaths around the city of Ibadan, 90 miles north of Lagos.   A dam overflowed, and the fact that drains were clogged with rubbish made the inundation even worse.    

Camps have been set up to accommodate the thousands of people who have been driven from their homes.  Buildings have been flooded, food destroyed, and farmland swamped.

Last year, more than 100,000 people were made homeless by floods in the country, while across western and central Africa as a whole, more than 300 people were killed.    The Niger river reached its highest level in 80 years, and there were severe food shortages in the aftermath of the flood, which affected half a dozen countries.

The African floods of 2007 were even more widespread, affecting 14 countries, disrupting the lives of 2.5 million people, and killing 250.  (See also my blog of March 19, 2009)