5 things you may not know about the Downtown Line 2
The public gets a preview of the new Downtown Line 2 today, ahead of its opening on Dec 27.
FOO JIE YING (firstname.lastname@example.org) looks at five things you may not know about the construction of our latest rail line
1. GEOLOGICAL CHALLENGES
It was a contrast of geological extremes. Towards one end of the Downtown Line 2 (DTL2), around Beauty World station, engineers had to deal with Bukit Timah granite, which is notorious for being extremely hard. It was so hard that tunnel-boring machines were prone to wearing out.
At Rochor, which has a completely different soil profile, engineers had to contend with a 30m-thick layer of marine clay.
As its consistency is "soft like peanut butter" - which means the ground could not support any loading - liquefied soil (a mixture of cement and soil) had to be added to replace the soft soil.
2. MORE THAN 1,000 BLASTS
About 50,000kg of explosives had to be used to blast the tough granite around Beauty World station.
The principal engineering officer in charge of the Beauty World contract, Mr Teo Beng Sai, said it took at least 1,000 blasts over two to three years to clear the granite to make way for construction.
A blast takes a mere few seconds, but the planning behind each explosion was extensive. Roads were closed for a few seconds till the rock blasting was done.
The road closure was merely a precautionary measure in case there were any flying pieces of rock, Mr Teo, 53, explained.
The amount of blasted rocks is enough to fill up 26 Olympic-size swimming pools.
It is also 1,047 times the weight of a four-cabin DTL train.
3. RACE AGAINST TIME
The complicated construction of the Rochor station required engineers to make sure that the work kept up to its hourly schedule.
As they had just five to six hours every night to work on the road diversions, time became an extra precious commodity.
Even a two-hour downpour - which meant construction had to be halted - brought about anxiety, said principal project manager Tang Man.
4. FINDING SPACE IN A CONGESTED AREA
The area around Rochor station was so congested that there was no space for construction to start without causing a huge traffic jam.
With the station spanning Rochor Canal Road and Sungei Road - both five-lane roads - as well as a 20m-wide canal, engineers had to devise a series of road diversions to create space for the machines to start work.
The engineers also dug a temporary canal to shift it out of construction's way.
In total, over 30 stages of traffic and canal diversions were created, mostly done at night to make sure traffic flow in the day was not affected.
5. AN ENGINEER'S PERSONAL TOUCH
Mr Teo's job was to ensure that the Beauty World station was built within the six-year deadline, and the six years spent on the project helped the engineering officer hone his skills in engaging angry stakeholders.
The station is close to residential areas and eateries and Mr Teo became the contact point for grievances related to the DTL2 construction.
He tried to solve problems as much as possible, including handing out ear plugs personally to those living in a nearby condominium.
When an eatery owner complained of a burst pipe after midnight, Mr Teo rushed from his home in Jurong West even though "I'm not a plumber".
His personal touch won his stakeholders over: In recent months, Mr Teo found people smiling at him instead of giving him the usual dagger stares, he said.
Pride and sweet relief for engineers
If there is one common thing that all engineers involved in the Downtown Line 2 (DTL2) project feel, it is one of overwhelming relief.
The DTL2, which runs through areas such as Hillview, Beauty World, King Albert Park, Little India and Rochor, will start operating on Dec 27.
"It is like seeing your child graduate and contribute to society. Maybe that was how my parents felt during my convocation," senior Land Transport Authority (LTA) project engineer Michael Tom, 27, said with a laugh.
It was a stressful period fraught with sleepless nights.
The pressure went up four years after the project started when Austrian tunnel contractor Alpine Bau filed for insolvency in 2013 - a move that shocked everyone.
"It was very challenging. Even at the planning stage, we couldn't allow for the slightest of mistakes. If one person didn't cooperate, I don't think we'd be able to (complete the project on time)," said the engineer of 5½ years.
He added that engineers have an attitude that nothing is impossible, even when they are entrusted with mammoth tasks.
For instance, LTA principal project manager Tang Man, 48, handled the $803-million Rochor and Little India contracts, the most expensive rail project to date.
He and his team had to divert Rochor Canal and Sungei roads as well as a canal that ran between the two roads. But the area was so congested that there was no space to start any form of construction.
For five to six hours in the wee hours of the night, Mr Tang's team toiled on the roads, diverting traffic bit by bit.
For these engineers, strange work hours became the norm. Sometimes, they stayed on site even beyond their work hours just to ensure everything went well.
LTA principal engineering officer Teo Beng Sai, 53, said his current work arrangement is tons better than that of his previous job, where he worked for contractors and sub-contractors.
"My wife of 20 years used to joke that she fell in love with a man who didn't go home," he said with a chuckle.
What bugged him more were the unexpected calls of duty - literally - in his six years spent handling the Beauty World contract.
Mr Teo, who's known as "Mr LTA" because of his white polo shirt, would get calls from residents and eatery owners whenever there were problems.
It got somewhat embarrassing for him to eat at the nearby eateries because everyone viewed him as the enemy and the cause of slow business and noise, he said.
Dagger stares were not new but Mr Teo notes that the glares have turned into wide smiles in recent months.
"A few years ago, they saw me as an enemy. Now we are friends," he said.
The DTL2 will start running only at the end of the year, but Mr Tan is already looking forward to his next rail project, the Thomson-East Coast line.
But for Mr Tom, it is a sentimental farewell, not just to the work site that has become his "second home" but also the friendships built over the years.
Most importantly, the project also taught him some personal lessons.
"(I learnt that) being a good engineer means that you have to be a good man. You need to have that integrity as an engineer," he said.