The Machchhu dam failure, also known as the Morbi disaster, is one of the worst dam-related flood disasters in the history of India. It happened on August 11, 1979, at Machchhu Dam then situated on the Machchhu river in Gujarat. Owing to exceptionally heavy rainfall, the dam burst sending a wall of water through the then Morbi town of Gujarat. According to estimates, the number of people killed in the mishap varied between 18,000 and 25,000.
The failure of Morbi dam or Machchhu dam was listed in the Guinness Book of Records as the worst dam burst. The failure is also known for being officially termed as an “Act of God”. However, the claims were debunked by the book ‘No One Had A Tongue To Speak’ by Tom Wooten and Utpal Sandesara. It pointed out the structural and communication failures that led to the occurrence and also exacerbation of the disaster.
The excessive rainfall led to massive flood and eventually to the breakdown of earthen walls of 4 km long Machchhu II Dam. The spillway capacity was 5663 m³/s whereas the actual flow caused by the rain was 16307 m³/s, almost three times the capacity of the dam. The floods of 12 to 30 ft hardly took 20 minutes to engulf the low-lying regions of Morbi industrial town lying 5 km below the dam. Among the huge damages caused by the disaster was the huge devastation of farmland leading to a fall in productivity of crops.
Later when the dam was reconstructed in the 1980s, its spillway capacity was raised to about 21000 m³/s, 4 times its earlier capacity.