Odisha Sun Times Bureau
Sambalpur, Jun 23:
Worried over the safety of Odisha’s Hirakud Dam Multi Purpose Project, authorities have sought the help of three top national agencies to arrest the siltation of the dam.
The authorities are worried over the threat posed to the dam by rapid siltation due to depleting forest cover in the upper catchment area and cracks in the spillways.
The Chief Engineer, Hirakud Dam Project, Biswajit Mohanty, has written to the three premier agencies–National Remote Sensing Centre, Hyderabad, IIT-Chennai and Central Soil and Material Research Station, New Delhi—to conduct a survey on the dam and suggest remedial measures to check the siltation.
According to a survey done in 2000, the death storage level (DSL) of the reservoir was 590 feet and 53.7 % of it has been covered with siltation. The live storage level (LSL) of the dam stood at 590ft-630ft with 17.16 % of it occupied by siltation.
Recurrent floods have resulted in increase in siltation level, thereby decreasing the water holding capacity of the Hirakud Dam Reservoir (HDR) by 27.57%, the report said.
During an underwater survey of the dam conducted in 2002-03, the dam authorities had spotted cracks and holes near the spillways of the main dam. The authorities had carried out repair of some of these cracks then.
In the 497-feet foundation gallery, there are as many as 212 pressure release holes and many of the holes are choked due to lack of proper maintenance, the report added.
“The chief engineer has written to National Remote Sensing Centre to ascertain the present water holding capacity of the dam through satellite imaging. Besides, the Oceanography Department of IIT, Chennai has been asked to find out the areas of siltation in the dam. Central Soil and Material Research Station has been urged to conduct underwater survey to find out cracks near the spillways of the dam,” said Yashobant Parida, executive engineer of Hirakud dam project.
The construction of Hirakud Reservoir Dam began in 1948 on the proposal of Central Water Commission (formerly CWINC). The dam was inaugurated by India’s first Prime Minister Jawaharlal Nehru in 1957.
Notably, the Hirakud Dam Multi Purpose Project spread over 74,592 hectare had irrigation, flood control, power generation, waterway transport and fishing on its agenda when it became fully operational in 1966.
It may be recalled that a high level team comprising members of the World Bank, Central Water Commission and Dam Safety department had visited the Hirakud Dam in April this year to conduct a survey for the construction of the proposed additional spillways to discharge flood waters from the largest reservoir of Odisha.