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Opening the floodgates

  • 14/10/2001

Opening the floodgates Deforestation in the Hirakud dam's catch-ments has led to heavy siltation. The dam stores less water than its estimated capa-city. The state government's study of Hirakud's sedimentation shows that every year 12,000 acre feet silt is deposited. Out of the 53 km upstream spread of the reser-voir, 50 km has been silted up. A study by the Sambalpur University's School of Life Sciences has predicted that by the year 2050, siltation will reduce the reservoir's storage capacity by more than half. The dam's lifespan has also decreased from the original 111 years to 77 years.

Sadhana Sathpathy of the Centre for Development Studies has studied the dam's effectiveness in controlling floods. Sath-pathy concludes the dam has failed to reduce the impact of flood on cropped areas. Her study shows that agricultural land affected by floods has increased from 0.14 million ha (before the dam was constructed) to 0.216 mha after the con-struction of the dam. Recently, the state government also admitted that at an aver-age, 0.9 mha cropped areas get flooded annually.

The Sambalpur University study states that the dam has not been able to control floods in Mahanadi. It indicates that the fre-quency of flood has increased: one in every 13.4 years before the construction of the dam to one in every 3.8 years after its con-struction.

To make matters worse, the state administration's mismanagement of the dam also causes floods. The 2001 flood was aggravated as the reservoir's sluice gates had to be opened suddenly in the face of threat to the reservoir's safety.

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