NOC issued to construct bridge across Adyar river

NOC issued to construct bridge across Adyar river
T. Ramakrishnan and P. Oppili


CHENNAI: The State government has issued a “no-objection certificate” for constructing a bridge across the Adyar river as part of the Chennai airport’s secondary runway extension project.


An order, issued by the Public Works Department last week, said that the Airports Authority of India should reimburse Rs.3.522 crore which was incurred by the PWD towards the construction of a check-dam at Manapakkam across the river. To enable the formation of the bridge, it had been decided to convert the check-dam into a bed-dam with a height of 0.30 metres. This was to support groundwater sustainability in the area.


The need for the government’s NOC arose because the recently constructed Manapakkam check-dam had to be disturbed if the bridge had to come up. As the check-dam would totally come under the operation area of the Airports Authority of India (AAI) after the bridge construction, it would be difficult for the PWD to operate the sluice valves of the check-dam and clear silt periodically. In May, the Authority’s General Manager informed the government that the AAI’s Board agreed to remit the cost of construction of the check-dam.


The government order of July 21, 2009 laid down several conditions to be fulfilled by the AAI.

The Authority should deploy flood safety mechanism on either side of the proposed bridge to ensure free flow of flood water. Soon after the construction of the bridge for the secondary runway and parallel runway across the river, the Authority should take care of the periodical maintenance including the desilting work within in its boundary. Otherwise it should remit the cost to the PWD for undertaking the annual maintenance works.

The Authority should provide adequate flood protection walls on either side of the river at places where the river was proposed to be covered for the project. The flood protection wall on the river’s left bank should be constructed along the river meandering portion for a minimum clear waterway of 130 metres. The Authority should also construct retaining walls on either side of the river front, both upstream and downstream, to avoid inundation.

The PWD authorities would have the right to enter into airport area to inspect the Adyar river at any time and the works suggested by PWD should be carried out by the Authority, the order said.

http://www.hindu.com/2009/07/28/stories/2009072857700200.htm