The same campaign that killed China's sparrows built a hundred dams across one province of Henan in ten years, the hydrologist who said the dams were too many and too weak was removed from the project, and in August 1975 sixty-two of them failed in a single night and drowned more people than any dam failure before or since. Banqiao was the showpiece, finished in 1952 to harness the Huai River, and when the Great Leap began in 1958 the slogan over it was water accumulation first. Reservoirs went up everywhere, built by peasants with baskets and shovels on the same timetable as the furnaces and the sparrow drives, to the same reporting standard. Chen Xing, the engineer who knew the basin best, said the province was building so many that it was raising the water table into the fields and the salt into the soil, and that Banqiao needed twelve sluice gates to pass a flood. It was given five. He was a rightist. He was sent away. The dam was called the Iron Dam. Typhoon Nina came up from Taiwan in the first week of August 1975 and stalled against a cold front over the Huai basin, and a year's rain fell in a day. Banqiao's five gates could not pass it. The water came over the top an hour after midnight, the dam dissolved, and a wall of water six miles wide and seven metres high went down the valley at the speed of a car, taking the next dam with it, and the next, until more than sixty had gone. Whole towns were under water before anyone had lit a lamp. The official figure for the flood is twenty-six thousand dead; the figure that includes the famine and the typhoid in the weeks after, when a province sat in standing water with the dead floating in it, runs to a hundred and seventy thousand, and some put it over two hundred. The Party kept it secret for thirty years. Chen Xing was brought back after the famine to say what he had said before, and brought back again after the flood. A sparrow weighs an ounce and a dam weighs a mountain, and the same men measured both by the number they could report, with the same result.