Preparing the land in Changi East for the airport's future Terminal 5 and third runway is challenging work, but so far it is progressing well.
A small part of the work is being done near one of the two existing runways, but this is carried out during lull periods so that travellers are not affected, said the Ministry of Transport (MOT) in a project update yesterday.
Site surveys, soil investigations and clearance works have been completed and the team is now focused on ground improvement works, said MOT director for air transport Chua Kwan Ping.
This includes treating and strengthening the soil at the site which is more than 1,000ha - or slightly smaller than the current airport premises.
Engineers in Changi East, currently separated from the airport by Changi Coast Road, are dealing with reclaimed land consisting of thick layers of soft marine clay which cannot support airport infrastructure and aircraft load.
Different ground improvement methods will be used, including mixing cement into the soft marine clay and inserting vertical drains to suck out excess moisture. At some parts, the land will need to be raised to mitigate the impact of a projected rise in sea level due to climate change.
Mr Chua stressed: "If the works are not done properly, the taxiways and runway could sink over time."
Related roadworks around the site, including the widening of Tanah Merah Coast Road and the construction of a new road between Tanah Merah Coast Road and Aviation Park, are ongoing.
The new road will replace the existing Changi Coast Road some time in 2017. Other major works such as canal diversion, and runway and taxiway pavement construction, will commence progressively from later this year.
T5 is slated to open around 2025 with an initial capacity of up to 50 million passengers a year - more than T1 and T2 put together.
All three runways are expected to be operational before that, to handle a growing number of flights at Changi Airport.
Despite some slowdown in passenger traffic at Changi in the last one to two years, the long-term prospects for the region's air travel market are strong, industry observers said.
The development of T5, as well as T4 which is currently being constructed next to T2 where the budget terminal used to be, is to ensure Changi has enough capacity to meet future needs.
This article was first published on May 28, 2015.
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