In response to severe flooding and to ensure electrical power generation, China built the Banqiao Dam in the Huai river basin of the Henan province. It was completed in 1952. However, they never imagined the dangers that would follow. [1] Due to construction and engineering errors, numerous cracks in the dam appeared after completion and were repaired by Soviet engineers. Chen Xing, one of China’s foremost hydrologists, was involved in the design and was a vocal critic of the dam’s final construction as well as the government’s policy. Chen had recommended twelve sluice gates for the dam, but only five were installed. Chen was involved in other dam projects, but due to his continuing voicing of safety concerns related to design and construction practices, he was removed from the projects.
In August of 1975, typhoon Nina pelted the region with the heaviest rains ever recorded in the area. More than a year’s worth of water fell in 24 hours. The previous record was 800 mm of rain, and the stalled typhoon Nina dropped a new record of 1060 mm in one day.
The rainfall caused massive downstream flooding and, because of the flooded downstream areas, one request to open the dam was rejected on August 6. On August 7, the request to open the dam was accepted but this information did not reach the dam, as the storm had brought down the telegraph wires. The under-designed sluice gates were unable to handle the water volume. The water crested on August 8 at 0.3 m. higher than the protection wall on the dam, which failed. Shimantan Dam and 62 other smaller dams in the Huai river basin also failed. The Banqiao Dam failure caused a huge wave, 10 kilometers wide and 3-7 meters high to rush downstream at 50 kilometers per hour, inundating the lower area. One estimate is that 26,000 people died from flooding and another 145,000 died afterward as a result of epidemics and famine. [1]. Some 5,960,000 buildings collapsed and 11 million residents were affected. Unofficial estimates of the number of people killed by the disaster have run as high as 230,000 people. The Chinese government tried their best to keep the accident a secret. By 1993 the dam was rebuilt, several meters taller. Since the Banquiao disaster the Chinese government became very focused on surveillance, repair, and consolidation of reservoir dams.
============================================ Seven county seats, Suiping, Xiping (西平), Ru'nan (汝南), Pingyu (平舆), Xincai (新蔡), Luohe (漯河), and Linquan (临泉) were inundated, as were thousands of square kilometers of countryside and countless communities. Evacuation orders had not been fully delivered due to weather conditions and poor communications. Telegraphs failed, telephones were rare, and some messengers were caught by the flood. While only 827 out of 6,000 people died in the evacuated community of Shahedian just below Banqiao Dam, half of a total of 36,000 people died in the unevacuated Wencheng commune of Suipin County next to Shahedian, and the Daowencheng Commune was wiped from the map, killing all 9,600 citizens. It has been reported that 90,000 - 230,000 people were killed as a result of the dam breaking. [2]
(See less)