Cuttack, April 14: Dismantling and removal of remains of a 150-year-old anicut upstream of Mahanadi barrage at Jobra is under way to prevent formation of shoals or deposit of sand close to the barrage's upstream and also to improve its flood release capacity.

The work, being undertaken after a gap of more than a decade, assumes significance as experts say that the remains of the old structure is a major cause of increasing sediment load upstream of the barrage and rising of flood level.

Barrage is a diversion structure. The storage in the pond upstream of the barrage caters to the variation of inflow and outflow according to the flow in the river. The anicut over Mahanadi was built in 1866 for irrigating about 3,95,378 hectares of farm lands in Cuttack, Jajpur, Kendrapada and Jagatsinghpur districts through a network of canals.

The new Mahanadi Barrage was constructed in the 1980s after it was felt that the old anicut would collapse anytime. The new barrage was constructed 60 metres downstream of the old anicut.

An official of the Mahanadi barrage division said that during the construction of the new anicut, dismantling of the old structure was done in front of 16 of the total 95 sluice bays of the new barrage. Immediately after operation of the barrage, formation of shoals in the upstream pond and increased sediment inflow to the irrigation canal was observed. After experts recommended dismantling and removal of the old structure as a remedial measure, dismantling of the old anicut in front of 36 sluice bays was undertaken during 2003-2005.

Dismantling of the remains of the old anicut in front of the remaining 43 sluice bays of the Mahanadi barrage was undertaken recently following intervention of Orissa High Court.

During the course of hearing on a PIL, expert reports submitted in the court indicated that the old anicut existing in front of the barrage bays was a major cause of formation of shoals upstream of the barrage, rising of river bed level due to increasing sediment load and rising of flood level.

The high court in an order on February 27, 2012, imposed a set of conditions on the Indian Oil Corporation Limited (IOCL) for drawing water from the Mahanadi in Cuttack for its refinery-cum-petrochemical project in Paradip.

As part of the set of conditions for drawing water from Mahanadi, the court had directed: "So far as removal of old anicut is concerned, it shall be done at the cost of Indian Oil Corporation under the supervision and technical guidance of state water resources department."

In pursuance of the court order, the IOCL had provided Rs 10 crore to water resources department in April 2015. The status of implementation of the order was taken up by the court recently. Progress report was submitted in the form of affidavits. Deputy secretary of water resources Prasanna Kumar Mishra said: "The work of dismantling and removal of old anicut has been awarded to Odisha Construction Corporation (OCC)."

OCC managing director Prasanna Kumar Mohanty said: "The dismantling of old anicut is in progress at all the balance 43 spillway bays."