Navi Mumbai remains the best possible site for the metropolis' proposed new airport and the suggested alternatives of Wada, Ansoli and Kalyan have bigger negatives, the City and Industrial Development Corporation told the visiting Experts Appraisal Committee on the issue on Sunday.
Cidco gave a presentation on the subject to the EAC members.
Which reiterated the several advantages it saw for the Navi Mumbai site, starting with the distance. It is 35 km from Mumbai, while the distance between Mumbai and Wada is 95 km, Ansoli is 70 km and Kalyan, 50 km.
Besides 78 per cent of the land is in possession of Cidco, and people living around the site are willing to relocate.
The site is proposed on the major InfoTech corridor of Mumbai-Pune.
Cidco says it is quite natural that the second airport for Mumbai come up near this corridor.
A Cidco official, who did not want to be named, told Business Standard that Wada was not acceptable as the glide slope was more than three degrees (three is the standard) and the Obstacle Assessment Surface penetrated by hills by 170 metres in the approach or take-off.
The Ansoli site was not acceptable as the OAS was penetrated by hills on either side of approach or take-off by 210 m and 57 m; the glide slope was also more than three degrees.
And, Kalyan's OAS surface was also penetrated by hills in its approach or take-off by 429 m; the glide slope was again more than three.
Moreover, in case of Newali (Kalyan), the runway orientation was not in accordance with the prevailing wind direction and there was obstruction on the flight path.
Incontrast, the Navi Mumbai site had no penetration of hills in the OAS and the glide slope was three.
Cidco admitted the residential population re-location is highest in the case of Navi Mumbai, followed by Asnoli, Kalyan & Wada.
However, the population was willing to re-locate, whereas the resistance to doing so weas visible in Kalyan.
Asnoli and Wada area residents don't want the airport, since most of the area is fertile and under agriculture.
Land acquisition is another issue. About 63 per cent of the land in other sites are in private ownseship; it is only 22 per cent in Navi Mumbai.
Also, a third of the area is forest land in case of Wada and Asnoli; the proportion is 10 per cent in Kalyan.
There is no forest land at the Navi Mumbai site.
Also, about a fifth of the Kalyan site is in possession of the defence ministry and also encroached by villagers.
A laboratory of the Bhabha Atomic Research Centre also exists within the intended airport area.
A Cidco official said they could make changes in the non-aeronautical area plan at Navi Mumbai, covering 415 hectares.
However, any changes in the aeronautical area of 1,200 ha would affect the project's viability. Cidco also explained to the EAC how the Gadhi river's diversion, a big concern, could be minimised without impacting the airport design.