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.