The Land Transport Authority announced that it had appointed Tritech Engineering & Testing (TET) (Singapore) Pte Ltd and Ryobi Geotechnique (Ryobi G) International Pte Ltd to carry out Site Investigation (SI) works for the direct alignment option of the Cross Island Line (CRL) under the Central Catchment Nature Reserve (CCNR) following the tenders called on 8 June 2016.
LTA said that this is the second set of SI works in addition to the skirting option which started in May 2016 that the Government is carrying out to analyse and determine soil conditions and engineering feasibility, so that an assessment on the alignment of the CRL can be determined.
The CRL is a 50km long new train line announced in January 2013 as part of Singapore’s aim to “improve the connectivity, accessibility and coverage of the rail network” to support Singapore’s potential growth in the future. The CRL is targeted to be completed by 2030.
TET, one of the largest SI works specialists in Singapore, has been appointed to carry out borehole drilling works (16 10-cm boreholes in total) to extract soil samples on existing trails and clearings in the CCNR. The company has extensive experience in borehole drilling, including in environmentally-sensitive areas. For instance, TET was involved in borehole drilling operations for the slope stabilisation studies in the Bukit Timah Nature Reserve and Bukit Batok Nature Park. TET has also conducted successful multiple horizontal directional coring in close proximity to underground oil pipelines and a gas-fired power generation plant on Jurong Island that were highly sensitive to ground movements and vibrations.
Ryobi G, supported by its subcontractor Geophysical Services Ltd (GSS), has been appointed to carry out geophysical survey works within the CCNR. The surveys will be used to supplement the limited data set obtained by the boreholes. GSS is a specialist in 3D seismic surveys, and has carried out several geophysical surveys in Singapore including on government projects such as the Thomson-East Coast Line and the former KTM corridor. As an added measure to reduce the impact to fauna, GSS will be using wireless equipment for their works.
According to LTA, the SI works for the CCNR will start in December 2016 and is expected to complete by 2017. Throughout the SI works, a team of LTA officers and the contractors will work closely with the National Parks Board (NParks) and the nature groups to ensure that all mitigating measures are rigorously implemented.
Both the direct and skirting alignment options are being studied. The findings from the SI works will provide inputs to Phase 2 of the Environmental Impact Assessment (EIA), which assesses the impact of construction and operations for the two possible alignments.
Only after the SI works, Phase 2 of the EIA, and taking into account the various concerns and considerations from all stakeholders as well as the potential impact on the CCNR, will the Government take a decision on the alignment.
It was stated that LTA has been co-operating with residents and nature groups over the past 8 months to deal with their worries on the building of the CRL as to how it might adversely affect the reserve with the construction of the line.
According to LTA, the nature groups put together a working group report that will be viewed in conjunction with an earlier position paper by Nature Society Singapore (NSS) to help find out how the different “possible alignment options could affect the CCNR”.
The construction of this CRL has been a controversial issue with nature groups since the idea was introduced and its impending construction through the CCNR has remained a concern with Nature Society Singapore, eco-activists and members of public.
Earlier in July 2013, the Nature Society released a position paper that states the soil investigation activities involving the core drilling of 70 metres deep bore holes along the alignment will cause tremendous permanent damage to the habitat. The society has since made recommendations to LTA for them to adopt alternative routes for to have the MRT line rerouted so to avoid cutting through the reserve.
In March 2016, Member of Parliament from the Yishun GRC, Mr Louis Ng Kok Kwang asked the Minister for Transport, Mr Khaw Boon Wan, about the main factors taken into consideration when deciding on the possible underground alignments in the vicinity of the CCNR for the CRL.
He also asked if the Ministry would consider the alternative alignment along Lornie Road which will allow the MRT line to serve more residents and commuters in that vicinity and will result in the protection of the nature reserve and primary forest.
In reply, Mr Khaw said that the alternative alignment to skirt around the nature reserve for the CRL will cost commuters six minutes of additional travel time. He said: “Some people say it’s just six minutes, but I’m not sure we can just brush aside the extra six minutes just like that because for MRT commuters, even an extra half a minute is terrible.
“We know this because when a train gets disrupted and there’s a one-minute delay, within that minute, they can send out maybe 100 tweets to flame LTA or SMRT. So one minute is a lot of time, let alone six minutes. That’s why in the rail industry, they define disruption as anything that causes a delay of more than five minutes and six is more than five.”
Mr Khaw added, “The skirting alignment on the other hand, is about 9km long… and because it is 9km long, it will require longer tunnels. And therefore, it would require ventilation shafts, ventilation facilities on the surface whereas the earlier option, because it is short enough…you do not have to build all those…exhaust ducts…These options could incur around 2 billion dollars in expenditure, 2000 million dollars and could result in land acquisition.”
Eco-activist, Teresa Guttensohn in an earlier interview with TOC, said:
“If the alignment of the Cross Island MRT Line goes underneath MacRitchie Forest, the potential disturbance can be considered destructive to the whole fragile rainforest eco-system and animals.
Major concerns are further fragmentation of the forest reserve, possible loss of habitats and endangered communities, soil erosion and stream siltation. For example, frogs and crabs will have trouble breathing when covered in silt. Sedimentation could mean significant loss of freshwater fish and amphibians found only in our pristine forest streams, which could in turn affect birds, reptiles and other animals that feed on them. Some stream fauna are found only in our central nature reserves such as the nationally endangered Temasek Shrimp (Caridina temasek) and Johnson’s Freshwater Crab (Irmengardia johnsoni).
Other possible negative impact could be potential noise pollution effects on sensitive wildlife for which MacRitchie Forest is an important refuge, e.g. rare mammals like the Sunda Pangolin (Manis javanica), which is internationally endangered, and the Sunda Slow Loris (Nycticebus coucang). Few Singaporeans have heard of or seen these special and secretive animals. Although we cannot accurately predict or know the actual total impact, we simply can’t take a risk with our forest reserves. Lost ancient eco-systems cannot be replaced.”