Transport Minister Khaw Boon Wan said in Parliament on Monday that Singaporeans should "keep an open mind" on the Cross Island Line's alignment.
He said a decision will take into account "potential impact on the nature reserve, the travelling distance and time for commuters, the cost to taxpayers, and the potential acquisition of homes and businesses".
"Go with the facts... and look for the evidence," he said.
It is sound advice, one which both proponents and opponents of the original alignment of the new MRT line should heed.
Expected to be completed in 2030, the 50km fully underground Cross Island Line goes from Changi, through Ang Mo Kio, Bukit Timah and West Coast, to Jurong Industrial Estate. Its proposed original alignment cuts through the Central Catchment Nature Reserve.
A recently completed environmental impact assessment expects site works will have a "moderate" impact on the gazetted nature reserve, despite the fact that the train tunnels themselves would run 40m or 12 storeys below the surface.
That is not good news to those who believe the reserve should be protected at all cost.
While various government agencies and ministries have come out to assure that works such as soil investigation will be mitigated and monitored closely, it behooves the authorities to make a case on why they feel so strongly about going beneath the reserve in the first place.
Up till now, no one in Government has acknowledged the slightest advantage of the Nature Society's proposed alternative, which skirts the southern fringe of the reserve.
Instead, the authorities have focused on the disadvantages. These include additional cost, a longer route and therefore additional travelling time, and the possible acquisition of homes - never mind that cost and travelling time are relative to the length and coverage of any mass transit project. That is to say, if you wanted to save more money and more time, go for an even shorter and straighter alignment that possibly misses even more populated areas.
As for land acquisition, the Land Transport Authority (LTA) has managed to build Singapore's rail network of around 180km in the last three decades with minimal acquisition of private property.
Even in densely built-up areas such as Chinatown, Bras Basah, Holland Village and Serangoon, the streetscape is left admirably intact. More often than not, it is state land that is acquired before private land.
It has been able to do this by safeguarding land along planned lines way ahead of time, and running the lines largely along road reserves. The Government has said that it cannot do this with the Nature Society's proposal because of its proximity to the Thomson-East Coast line.
That may well be the case.
Still, we have had lines that are very close together, such as the North-South and East-West lines at Raffles Place and City Hall, and the Circle and Downtown lines between Promenade and Bayfront.
The Transport Ministry has also admitted that it is good to have some redundancy in the system, so that when one line breaks down, commuters have an accessible alternative. Several neighbourhoods are served by more than one MRT station, such as Little India, Serangoon, Chinatown and Outram.
In Marina Bay, no fewer than six stations on four MRT lines will converge in an area no bigger than Sengkang. Everyone who lives or works there will be able to get to a station within five minutes.
Granted, the Thomson-Lornie area is no Marina Bay. But this shows that if there is a will, there is a way.
The Nature Society's skirting proposal - imperfect as it may be - allows the line to serve developments along Thomson, Lornie and Adam roads, not to mention the massive future Bukit Brown housing estate.
Straits Times reader Dennis Chan also points out that the alignment of the line could be reconfigured so that it serves areas such as Balestier, eastern Toa Payoh and Serangoon Gardens, which are currently not served by the MRT.
Either option will be preferable to the original from a transport viewpoint. In fact, any alignment along a populated area would be superior to one that traverses an unpopulated area.
And if the Government's aim is to have 80 per cent of homes within a 10-minute walk of an MRT station, realigning the Cross Island Line to serve new areas is imperative. It makes little sense to build a line under a forested area - much less one that is protected by law - unless there is truly no other alternative.
And so far, the Government has not made such a case.
In addition, trains running beneath the reserve might pose safety concerns. The LTA has said that the stretch across the nature reserve will have no surface structures.
This means that if a train stalls along this stretch, commuters may have to get out and walk 1km or more to the nearest station. In such an unfamiliar environment, with sub-optimal lighting, a crowd in excess of 1,000 - a six-car train accommodates around 1,400 - might take 30 minutes or more to cover that distance. And should there be a fire, the consequences would be unthinkable.
To be fair, Mr Khaw has said that more studies are needed on the environmental and engineering impact of the line. Public consultations will also be conducted.
The first environmental impact assessment took two years. It may thus take two years or more to complete another environmental impact assessment, on top of technical studies, to reach a decision, Mr Khaw said.
In the interim, members of the public and activist groups should do as Mr Khaw advised - keep an open mind.
Equally important, government officials would have to do likewise.
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