Narrate how particular dam in a flood-prone area has recently failed to prevent a flood. Find out why it happened. Could this be avoided? How?
Answers
Answer:
There is no sign of floods abating in Odisha. In the space of a fortnight, the number of people affected by the deluge in the Mahanadi river, the state's largest riverine system, increased from one million to 2.2 million on September 13. Two-thirds of the state's 30 districts are affected.
The flood has impacted all those districts along the Mahanadi which are downstream of Hirakud multipurpose dam in Sambalpur district. This happened despite the fact that the dam, commissioned in 1958, was meant to control floods in the delta areas. Right now, the water level is receding in west Odisha, while the districts along the coasts like Cuttack, Jagatsinghpur and Puri continue to be marooned because of flood waters. A massive relief operation is underway amid allegations about its inadequacy.
The Hirakud dam, just a few inches short of its maximum storage level—the reservoir level was 629.08 feet (191.7 metre; one foot equals 0.30 metre) against the full reservoir level of 630 ft—opened 59 gates on September 9. It unleashed a flood considered the worst ever in the state. The flood of 2008 was the last such severe flood after the one in 1982. The gates remained open for two consecutive days. Going by what officials in charge of the dam have to say, unprecedented rainfall in Chhattisgarh, which accounts for 85 per cent of the river's catchment area, led to a huge inflow of water into the dam's reservoir that used to be hardly ever full. On September 7, the dam's storage level was at 625.60 feet when 10 gates were open. This meant that within 48 hours the Mahanadi received five times more water.
Answer:
Reasons of flood could be :
- Construction of dam would have been weak.
- Excessive rain would have taken place.
- Melting of ice & rain in wrong season leads to flood.
- This could be avoided
If man made mistake is prevented.
If pollution is avoided.