SINGAPORE — The Cross Island Line (CRL) will be built under the direct alignment option running 70 metres under the Central Catchment Nature Reserve (CCNR) to minimise its environmental impact.

In a media release on Wednesday (4 December), the Ministry of Transport (MOT) said that the option for the CRL was chosen following a comprehensive two-phase Environmental Impact Assessment (EIA) and discussions with various stakeholders.

Transport authorities had considered the skirting alignment option for the CRL.

At 70 metres below ground level - compared with the typical 20 to 30 metres underground - the depth of the two kilometres stretch of the direct alignment route is equivalent to the height of a 25-storey HDB block, making it the deepest rail tunnel in Singapore.

In comparison, the skirting alignment option would require a depth of 45 metres.

View photos Direct alignment for the Cross Island Line under the Central Catchment Nature Reserve. (IMAGE: Ministry of Transport) More

The tunnel length for the direct alignment option is 4km with 2km tunnelling under the CCNR, compared with the 9km tunnel length under the skirting alignment option.

The direct alignment option will benefit Singaporeans in several ways, the MOT said.

The commuting time would be reduced by about six minutes per commuter per trip compared with the skirting alignment option while public transport fares would be 15 per cent lower due to a shorter and more direct route.

The construction costs would also be lower by $2 billion. In the longer term, the option is also more environmentally friendly due to lower energy consumption.

Addressing reporters on Wednesday evening (4 December), Senior Minister of State for Transport and Health Lam Pin Min stressed that authorities had taken pains to engage the various stakeholders over six years, from nature and heritage groups to residents and grassroots leaders.

Noting that there had been more than 40 engagement sessions with the nature groups, Dr Lam said that transport authorities hope to continue drawing on their expertise and experience. “I hope that this will not be the end of the journey working together. In fact, it is only the beginning (and we want to) together co-create some of these mitigating measures.”

Following feedback from nature groups, authorities have also committed to locating and optimising the layout of two worksites outside the CCNR.

The Land Transport Authority is currently in talks with the Singapore Island Country Club to use a part of its non-playing area. A second worksite, located on the western edge of the CCNR, will be subject to a future advanced engineering study.

No time frame was given for when works would begin.

The CRL - Singapore’s eighth MRT line - will be the longest underground MRT line, spanning from Changi to Jurong Industrial Estate. It will be more than 50 km long and have almost half of its stations as train interchanges.

Commuters travelling from east to west, for example, can expect to enjoy travel time savings of between 30 and 45 minutes when switching to the CRL.

In the initial years, the CRL is forecast to have a daily ridership of more than 600,000, growing to more than 1 million in the longer term. Phase I of the CRL is projected to be operational by 2029.

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