Plans to build two drains at Delhi airport to end waterlogging fail to take off
Last Saturday, Delhi residents woke up to videos and images of a heavily inundated Indira Gandhi International Airport (IGIA). As shocking as the videos were, airport officials say the waterlogging is nothing new; it happens every time there is a downpour. However, a solution has eluded them so far, with plans to construct two wider drains failing to take off even three years after they were conceived for want of clearances from agencies.
Officials of the airport operator, Delhi International Airport Limited (DIAL), said for the past three years, they have been in talks with Delhi Development Authority (DDA) and the public works department (PWD) to build the two drains, wide enough to accommodate all run-off water in the event of a downpour.
A senior DDA official, in the know of project details, said, “The work on one drain has been awarded but we are awaiting tree-felling permission from the forest department.”
Spread over 5,000 acres, the Delhi airport is divided into two parts -- the northern air parcel and the southern air parcel. Even though water accumulates on both sections, it is the northern side that is the worst affected. It is also the side that houses Terminal-1 and Terminal-2, said officials.
A senior airport official said while one drain is awaiting clearance from the forest department, the other is yet to get a right of way approval from the DDA, despite having all clearances from other agencies, including the PWD, the agency constructing the drains.
Airport officials said the drain is much needed, especially on the northern air parcel. “The DDA’s artillery drainage network, which is 2.5 metres wide and one metre deep, is inadequate to handle the storm water. Even 20mm of rainfall is enough to cause flooding on the northern side, with rainwater from the Mahipalpur junction flowing into the northern access underpass and inundating the area. There is no drainage facility in the vicinity to restrict water accumulation, and this water enters the northern side and gets accumulated at the western end of the northern main runway funnel area,” an airport official said, asking not to be named.
As for the southern side, there is an existing four-cell box culvert drain -- about 12 metres wide and 2.75 metres deep. It can only handle a rainfall intensity of around 60mm before becoming causing waterlogging towards the forecourt of Terminal 3 (T3).
A second airport official said a steep land gradient of 17 metres, between NH8 and T3, only makes matters worse with water from Radisson hotel and its adjacent areas also gushing towards the airport.
Saturday’s waterlogging, which was cleared in about 30 minutes, took place due to the steep gradient between NH8 and T3, the official said. “The entire area acted as a catchment and drained water towards the terminal. DIAL has been working with state and central government bodies and officials for the past few years requesting to widen this underground drainage system. Several discussions in this matter have already taken place,” the official said.