The secondary runway, which was initially 2,035 m long, was closed in 2009 to extend it over the Adyar river by means of a bridge over the watercourse at a cost of 4,300 million. Initially, 126.59 acres of land for second runway was handed over to the AAI. In March 2011, by acquiring 136 acres of land from the state government, AAI completed extension of the 2,035 m secondary runway by 1,400 m, whose commissioning, initially planned to be by November 2011, has been delayed as the approach lighting system has not been installed. While the cost of extending the runway was projected to be about 2,400 million, that of the bridge is almost 2,300 million. A bridge has been constructed across the Adyar river to extend the secondary runway by a length of 1,400 m to a total length of 3,445 m, including 835 m on the northern side of the river. The bridge accommodates the runway and a taxiway, making Chennai airport the only international airport in India to have a runway across a river. In Mumbai, only an end of the runway is over Mithi river. When the AAI recommissions the secondary runway, Chennai airport will join the league of airports with a functional runway across a river.