Would it make sense to build an underground LRT system, for example, a Jurong Regional Line or an AMK Regional Line?

Tunnel boring costs would be much lower than for MRT because the tunnels would be about a meter smaller in diameter. Also, the interstation spacing would probably obviate the need for ventilation shafts between stations.

I could imagine a loop running from AMK MRT station west along AMK Ave 3, interchanging with the TSL, running out to James Cook University, then north to Teachers' Estate, then east to YCK Gardens and interchanging with the TSL, then interchanging with the NSL at YCK station, then Nanyang Polytechnic, then near Anderson Secondary School, and then closing the loop back to AMK station. Of course, we don't yet know where the TSL stations will be, but there will certainly be at least one in the vicinity -- and one would suffice. In addition to the local passengers, some passengers would use the line to transfer between the NSL and TSL rather than going all the way down to Thomson or up to Woodlands.

Land use would be minimal. At interchanges with the TSL stations, no new exits would be needed. At other stations, two exits would be needed for safety reasons, but they would not need to be much larger than a bus shelter. Because NSL stations are, sadly, above ground, it probably doesn't make sense to try to integrate them at the platform level i.e. inside the fare gates.

AMK isn't a good candidate for an underground LRT. AMK is probably one of the few towns that is more "spacious" because of the wide roads, and elevating it would be just fine. Using latest technologies, the trains themselves, with fade-out windows and softer engines, along with cleaner designed stations (I see Vancouver, some of KL and Bangkok's stations and wonder why our LRT station designs look so boxy and all), is more cost-effective. Afterall, URA/LRT seemed to have had plans for an AMK-Hougang LRT in Concept Plans for the longest time.

However, I don't think Singapore's versions of the LRT is the smartest thing. What I'd look at is more VAL-like systems like the Vancouver Skytrain, or some lines of the Paris Metro, Bangkok BTS and some of the RapidKL lines as being more suitable for lines like the Jurong Region Line at which even a Downtown Line-esque 3.2m wide 3-car is too much and not cost-effective. You don't take a people-mover system designed mostly for airports and think it's the ultimate solution to provide feeders to metros. That, in my opinion, is one of LTA or whoever's biggest blunders.

Having certain infrastructures elevated also has a dual purpose of being a landmark, and this purpose is quite obvious in the EWL Tuas extension. The NEL also suffered this problem somewhat because regular commuters aren't transport-savvy, and may not have known how near it was or where the station came up to. I know tonnes of people who didn't know Kovan was referring to Hougang South. Sometimes, the best way to attract commuters is to use trains is to show them that it's there, all of it in its full glory.

The idea is definitely worth investigating. Not even LRT as we know, just an underground tram like in some European cities would do the trick of taking the feeder network off-grade.

I think it would be possible to connect the platforms on majority of EWL and NSL platforms though, if they did it for CCL. The very first candidates could be Tampines, Bedok, Clementi, Jurong, perhaps Yishun and Toa Payoh/Bishan.

Who knows, perhaps the express could also be LRT if the demand doesn't satisfy the heavy rail...Well, it still all depends on how much cheaper the smaller tunnel is and what LTA finds purposeful.

ddes, you make some good points. However, while above-grade rail may be a landmark for a while, it eventually becomes an eyesore. It also constrains future redevelopment of the area. Nearly all the above-grade metros built about a hundred years ago have been torn down. All or nearly all the below-grade metros built about a hundred years ago are still operational.

Sure, whenever a new rail line is built, it takes some people longer than others to figure out where the nearest station is. I'm sure people learn faster when the stations are more visible, but eventually everyone learns.

The idea of an LRT line (or whatever one calls a line lighter than the CCL and DTL, like the Paris Metro lines) connecting the TSL, NSL, Seletar Line and NEL makes a lot of sense to me. It might even make sense to tunnel under Paya Lebar Airbase and connect to Tampines.

dun think it will happen lah, there is no economies of scale to sustain the line.

Viaducts are still cheaper options compared to underground tunnels. Going underground require PSD at station and air conditioning the stations as well as putting escalators if needed. This will incur operating expenses and skyrocket the electrical bills for merely smaller stations. This will translate to additional costs compared to maintaining buses.

However, while above-grade rail may be a landmark for a while, it eventually becomes an eyesore. It also constrains future redevelopment of the area. Nearly all the above-grade metros built about a hundred years ago have been torn down. All or nearly all the below-grade metros built about a hundred years ago are still operational.


Tuas extension was not planned for "landmark" purpose. Viaduct is chosen because it is cheaper and sustainable in long term runs. If underground tunnels are used, the Government has to think how to make 5 underground stations sustainable when the traffic in Tuas is relatively lower during off peak hours.

As you mention - above grade metros are taken out. This is because the metro systems that were built years ago, were not designed to handle larger and heavier modern trains. So modern trains cannot use aging structures. So these structures need to be dismantled for safety purposes. If these are still used, the structures would crack and ready to collapse under strain.

Underground tunnels are more stable compared to aging structures of steels due to maximization of thick concrete walls. This is why tunnels are still being used.

Our MRT viaducts are made of concrete and steels and engineered to last hundred years in good maintenance conditions.

JediAlf, you make some good points, but an underground station doesn't need escalators any more than an above ground station.

No doubt, any MRT or LRT solution, whether elevated or underground, is more expensive than buses. However, they are also faster than buses, which increases productivity, as well as not taking up the precious land that is needed for roads to the extent buses are used.

Underground rail lines still cost more to build than elevated lines if one ignores the cost of land and the cost of constraining future redevelopment of the area. However, the cost of tunnel boring is continuing to decline while the cost of elevated rail has been increasing. Any new lines after the DTL, TSL, and ERL are more than ten years away and the relative costs will be different from today.

The capacity of air-conditioning needed for an underground station is roughly proportional to the peak number of passengers who will be using it. There is not much economy of scale for air-conditioning, so the cost burden on fares would not be materially different for a small underground station than a large underground station.

I believe any cost difference in building an underground station versus an elevated station is more than offset by the opportunity cost of not being able to build anything else above an elevated station. Also, maintaining elevated concrete structures past about 50 years is expensive.

Lines like the NSL, EWL, NEL, CCL, DTL, TSL, and ERL (and the future Holland and Seletar lines) that convey passengers long distances (5 to 20 kilometers) between the heartland and the CBD need the one to two kilometer interstation spacing and 100 kmh speeds that they have.

However, LRT, the future North Shore Line, and a hypothetical AMK-Hougang-Tampines line connecting the TSL, NSL, NEL and EWL/DTL would carry passengers who, for most trips, are just trying to get to the nearest MRT line. I believe the vast majority of trips on these lines would be less than five kilometers, largely replace local rather than long-distance buses. For such lines, LRT interstation distances and 70 kmh speeds are ok.

Another advantage of underground versus elevated LRTs is that they can use steel rails rather than rubber tyres on concrete guideways, reducing energy and maintenance costs.

The number of daily MRT passengers is now just over half the number of daily bus passengers. By 2020, there will probably be more daily MRT passengers than bus passengers. If we look at cities with well-developed metro systems like Paris and Moscow, we see very different ratios. In Paris, the number of daily metro passengers exceeds the number of daily bus passengers by nearly 5-to-1. Moscow has an even higher ratio of metro passengers to bus passengers. Both of these cities are continuing to expand their metro systems in order to get more buses off the streets, reduce commute times, and increase productivity.

For Singapore to reach where Paris is, we would need 1000 to 1200 stations. Most of those don't need to be the large MRT stations we now have serving heavy rail lines with one to two kilometer interstation distances. Most could be light rail lines with 500 meter typical interstation distances, more like the Paris metro or our LRT. However, criss-crossing the whole island with elevated LRT lines would, in my opinion, be a disaster in terms of quality of life. I'd like to eventually see 1000 kilometers of rail with 1200 stations, but only if it will be underground.

What I'm sure we won't ever see is 4500 rail stations to replace the 4500 bus stops now in use. However, I think most commuters would rather walk 300 meters to a rail station than 150 meters to a bus stop.

However, LRT, the future North Shore Line, and a hypothetical AMK-Hougang-Tampines line connecting the TSL, NSL, NEL and EWL/DTL would carry passengers who, for most trips, are just trying to get to the nearest MRT line. I believe the vast majority of trips on these lines would be less than five kilometers, largely replace local rather than long-distance buses. For such lines, LRT interstation distances and 70 kmh speeds are ok.

Another advantage of underground versus elevated LRTs is that they can use steel rails rather than rubber tyres on concrete guideways, reducing energy and maintenance costs.


Northshore Line is likely to be medium line - probably connecting to ERL in east and TSL in north, in future...

Debating over LRT underground vs LRT elevated, concrete guideways reduce maintenance and last longer than steel rails. Because the steel rails wear out very fast and they have to be replaced constantly. Rubber tyres can enable trains to climb on steep slopes. This is why our BP and Sengkang/Punggol LRTs are all running on rubber tyres.

Steel wheels also have to be replaced constantly. Rubber Tyres just get replaced once they are worn out. However, steel wheels require less energy to roll.

These wheel gears do not depend on underground or elevation. It depends on the weight of the trains and the loads of people. If the LRT goes over long mile carrying many people, steel wheel is better choice, hence Kelang Jaya line trains running on steel wheels.

If the city wants quietness, then tyres would be the choice.

If the city wants quietness, then tyres would be the choice.

If the city wants quiet, then underground would be the choice. ;)

Steel wheels and rails don't need to be replaced nearly as often with light rail as they do with heavy rail. Inclines should not be an issue underground.

I'm still hoping the North Shore Line will be fully underground and have interstation distances of about 500 meters. That would help make the north shore a very attractive place to live, despite the distance from the CBD.

Personally, I feel if the argument for placing LRTs below ground is merely for aesthetic purposes, then it isn't a very compelling argument for LRTs to go underground.

But first, can we establish the LRT we in fact, are talking about, is not the Punggol/Sengkang/Bk Panjang concept? Unless you are referring to it.

If we can get that out of the way, it's much easier to discuss because I believe some forumers may see this underground LRT as being nothing more than an underground BRT system. And we'll in the end, be merely arguing on the different definitions of MRT and LRT.

If the city wants quiet, then underground would be the choice. ;)

Steel wheels and rails don't need to be replaced nearly as often with light rail as they do with heavy rail. Inclines should not be an issue underground.

I'm still hoping the North Shore Line will be fully underground and have interstation distances of about 500 meters. That would help make the north shore a very attractive place to live, despite the distance from the CBD.

Singapore is very very thorough. They will check the rails and replace them. Steels are very expensive. Steel rails do crack. So the cracked ones will be cut and replaced. This results in higher maintenance costs and add $$$ to the fares.

Going underground is not always the best solutions applicable to all rail lines. It depends on where the line goes. In Tuas, it would be financially sense if it is in elevated section.

Simpang is the last town in Northeastern - between Woodlands and Yishun. It will be eventually developed down decades later. This is where it will be connected via Northshore line.

Personally, I feel if the argument for placing LRTs below ground is merely for aesthetic purposes, then it isn't a very compelling argument for LRTs to go underground.

But first, can we establish the LRT we in fact, are talking about, is not the Punggol/Sengkang/Bk Panjang concept? Unless you are referring to it.

If we can get that out of the way, it's much easier to discuss because I believe some forumers may see this underground LRT as being nothing more than an underground BRT system. And we'll in the end, be merely arguing on the different definitions of MRT and LRT.
Aesthetics are far from the only reason for building rail lines underground. Compared to elevated rail, underground rail has the advantages of:
- much longer-lasting,
- uses much less precious land, and
- does not constrain future redevelopment of the area.

I don't want to descend into a semantic argument and don't care much what names are given to lines, but the concept I'm thinking of has these characteristics:
- lighter than current MRT lines e.g. 2.6 or 2.8 meter wide cars,
- average interstation distances of about 500 meters, like LRT and the Paris Metro,
- fully underground,
- either rubber tyres or steel rails,
- each line connects residential areas with two or more medium/heavy MRT lines,
- line lengths of 5 to 25 kilometers,
- orientation typically perpendicular to the medium/heavy MRT lines running into the CBD, and
- a majority of trips would be local feed to heavier MRT lines, but some traffic would be purely local and some would be passengers wishing to transfer from one heavier MRT line to another.

For example, lines running roughly north-south and interchanging with the DTL3, EWL, and ERL. Each might be 5 kilometers and have 10 to 12 stations including 3 interchange stations.

I could imagine one such line running from the ERL through Siglap, interchanging with the EWL and DTL3, then continuing north along the western side of Bedok Reservoir and running up Tampines Ave 8, serving Tampines Retail Park, Meridian Junior College, and interchanging with the North Shore Line. It would be about 10 kilometers could have about 20 to 25 stations including interchange stations.

Singapore is very very thorough. They will check the rails and replace them. Steels are very expensive. Steel rails do crack. So the cracked ones will be cut and replaced. This results in higher maintenance costs and add $$$ to the fares.

Going underground is not always the best solutions applicable to all rail lines. It depends on where the line goes. In Tuas, it would be financially sense if it is in elevated section.

Simpang is the last town in Northeastern - between Woodlands and Yishun. It will be eventually developed down decades later. This is where it will be connected via Northshore line.
Steel rails do occasionally crack, though less often with light rail than with heavy rail and not so often in Singapore due to stable temperatures. Whether steel rails or rubber tyres, there will need to be regular inspections and maintenance. My point about steel rails versus rubber tyres was just that, by going underground the noise advantage of rubber tyres is obviated, so steel rails might make sense where they do not for elevated lines. The Paris metro uses both.

I also expect that the North Shore Line will serve Simpang and that development of Simpang will probably coincide with construction of the North Shore Line. Regardless of the weight or capacity of the North Shore Line, I think it would be a great candidate line for 500 meter average interstation spacing, because I believe a majority of passengers will be using it to get to the nearest MRT line heading into the CBD.

^^I've gotta confess I'm not too confident about of your proposed usage. Traffic patterns need to be rather established and specific for such feeder lines to work. Unlike the medium/heavy metros we have or going to have, the lines you are proposing is a feeder so it will need to prove that it is an advantage that it is better than buses. Stations will have to be strategically located so that people need only to use this system to get home or to work if not any advantage is gone. If there is a hole in which that there are commuters need to take a bus along your proposed line's alley, then it's a failure.

I'd be more supportive if the envelope is pushed more towards the extreme; "Paris Metro"-ing a large part of the island with such lines, while our 6-car lines take a backseat in terms of frequency and be relegated to commuter rail status. Therefore, a large part of Singapore households will be at most 400m to the nearest rail line. So essentially, it means Singapore has uniquely built its commuter rail first then its "real" metro later.

If this should be the case, the 3-car train lines ends with the TSL and ERL. Most lines after them, like the Seletar and Holland Lines should go "lighter" after that.

Also, I'd like to add that the "Paris Metro"-ing will put an end to large new towns. Towns like AMK can be segregated into Kebun Bahru, Yio Chu Kang, Teck Ghee, AMK East with the land around the stations the new "centrals" of these smaller towns, thus providing a more closely knit social environment for people.

^^ ddes, I agree with all your points above. The obvious place to look for opportunities to build Paris-metro type lines would be along whatever bus corridors emerge after construction of the Holland, Seletar, and North Shore lines. The Holland and Seletar lines, at least, need the scale of the CCL/DTL to quickly bring commuters into the CBD. After that, I think lighter underground rail with much closer interstation spacing (like LRT and the Paris metro) should be tried.

You're absolutely right that stations need to be spaced closely enough to obviate any need for buses along the route. I would think 500 meter interstation spacing would suffice but, taking a look at all the bus routes still serving the area served by the BP LRT, one wonders. Most of those are long distance bus routes to the CBD that, hopefully, will go away when DTL2 opens. Some go to Woodlands and some are local. Why does Bukit Panjang need local bus service to supplement LRT service? There are housing blocks in Bukit Panjang as far as 600 meters from the nearest LRT station. I think any light Paris-metro type lines need to be spaced to ensure that nearly all mid-rise and high-rise residences are within 400 meters of a station.

It might take 50 years but, ultimately, I would like to see all the bus services (except perhaps for night buses) replaced by underground light rail.

How many such lines would be needed to provide complete coverage for all the midrise and highrise residences in Singapore? I'm guessing that about 300 square kilometers is or will be covered by midrise and highrise residences. If the average Paris-metro type line will be 20 kilometers with 500 meters interstation spacing, that's 41 stations minus 2 or 3 since interchange stations shouldn't be counted multiple times. One station in isolation would cover 0.5027 square kilometers (within a 400 meter radius). However, the overlapping (400 meter) coverage of adjacent stations spaced at 500 meters is 0.1305 square kilometers, so a line with 38 new stations would cover 14.144 square kilometers -- if there were no overlapping coverage with parallel lines. In the real world, we'll probably see about 12 square kilometers of new coverage from a 20 kilometer line of the type discussed. Assuming that we'll have about 180 unique MRT stations once the Holland, Seletar, and North Shore lines have been completed, providing 400 meter radius coverage to about 50 square kilometers of residential areas, then about 250 square kilometers of residential areas would still need coverage. That would require about 400 kilometers of Paris-metro type rail lines, not counting coverage of industrial areas or low-rise residential areas. Altogether, about 500 or 600 kilometers of underground light rail in addition to about 300 kilometers of medium-to-heavy rail (existing, planned, and mooted MRT lines) should obviate the need for buses.

With less expensive (smaller bore) tunneling and much smaller but more numerous stations, the cost per kilometer would probably be similar to that for MRT lines. A construction rate of 10 to 20 kilometers per year seems plausible, starting in the 2020s.

Keeping the growth rate of private vehicles at 1% per year and gradually removing the buses would obviate the need for new expressways after the NSE. Commutes would be shortened for most Singaporeans and productivity would increase.

Replace all buses with light rail? Interesting.

When trains break down in several lines at same time, how are you going to solve the huge congestion of traffic building up at the stations? Obviously, we need buses on the roads to get them resume the journey.

On a 5 km line, if you put 5 stations apart, the travelling time is short (2 mins interval at every station = 10 mins). Put 10 stations, the travelling time will beome 20 mins. The more stations you put in, the travelling time is longer. Only one thing is that trains must stop at every station if there are no 4 tracks at every station. Buses are smaller in capacity but still very efficient. They are able to use every road and have no restrictions in any directions. Light rail has restrictions because it cannot go to any direction and has to follow the alignment of lines.

With bus lanes (painted with red and yellow lines), buses can speed past. Buses can skip bus stops if there are no passengers at the stops. Buses can provide express services or regular services. Although our MRT lines multiply over years, buses still are needed to supplement to MRT lines. Tokyo, London and Paris have huge rail networks but they still need bus services where their rail services could not reach. Trams are getting popular in European cities and they have limits to the extent because not all roads will be taken up by tram lines.

You cannot probably put many LRT lines for every major road. It is not practical in long term runs.

Replace all buses with light rail? Interesting.

When trains break down in several lines at same time, how are you going to solve the huge congestion of traffic building up at the stations? Obviously, we need buses on the roads to get them resume the journey.
The probability of simultaneous failure of several rail lines is about as likely as the simultaneous collapse of several expressways. Should we have a fleet of helicopters ready to get commuters past collapsed expressways?

If an MRT line (let's say the EWL line, for the sake of discussion) were to break down, having perpendicular LRT lines running north/south and connecting to the DTL3 and ERL would allow the passengers to get to their destinations. Yes, there would be crowding on the DTL3, ERL, and connecting LRT lines, but commuters would still complete their journeys faster than by exiting the station and looking for a bus.

On a 5 km line, if you put 5 stations apart, the travelling time is short (2 mins interval at every station = 10 mins). Put 10 stations, the travelling time will beome 20 mins. The more stations you put in, the travelling time is longer.
That's true, which is why I suggested that these lines generally be oriented perpendicular to the faster heavier NSL, EWL, NEL, CCL, DTL, TSL, ERL, Holland Line and Seletar Line running into the CBD. For nearly all trips, passengers would be travelling just a few stops on a light line.

Buses are smaller in capacity but still very efficient. They are able to use every road and have no restrictions in any directions. Light rail has restrictions because it cannot go to any direction and has to follow the alignment of lines.

With bus lanes (painted with red and yellow lines), buses can speed past. Buses can skip bus stops if there are no passengers at the stops. Buses can provide express services or regular services.
Yes, but light rail is still faster and cleaner. Trip times are less and frequencies can be higher.

Although our MRT lines multiply over years, buses still are needed to supplement to MRT lines. Tokyo, London and Paris have huge rail networks but they still need bus services where their rail services could not reach.
The Paris metro carries nearly 5 million passengers per day. Paris buses carry fewer than 1 million. Paris is continuing to build to new metro lines to further reduce the dependency on buses. Singapore will need buses for at least another 50 years, but the dependency can be reduced over time and eventually eliminated (except for night buses).

You cannot probably put many LRT lines for every major road. It is not practical in long term runs.
It is not necessary to put an LRT line under every major road. Just running them perpendicular to the MRT lines, at appropriate spacing, would suffice. As I outlined above, about 500 to 600 kilometers of underground LRT would probably suffice.

Bukit Panjang is illustrative. Look carefully at all the bus services in Bukit Panjang, individually and collectively. For each one, ask yourself: Why is the current MRT/LRT coverage not sufficient? Will the DTL2 obviate the need for this bus service? How much MRT/LRT coverage would be needed to obviate the need for any buses in Bukit Panjang?

The probability of simultaneous failure of several rail lines is about as likely as the simultaneous collapse of several expressways. Should we have a fleet of helicopters ready to get commuters past collapsed expressways?

Bukit Panjang is illustrative. Look carefully at all the bus services in Bukit Panjang, individually and collectively. For each one, ask yourself: Why is the current MRT/LRT coverage not sufficient? Will the DTL2 obviate the need for this bus service? How much MRT/LRT coverage would be needed to obviate the need for any buses in Bukit Panjang?

Expressways have alternative options and have numerous exits. When one section is affected, road traffic is diverted. Rail lines carry thousands of people who have no alternative options.

For example, Jurong East-Redhill section. Queenstown and Jurong East have cross tracks. If there is train accident at Commonwealth, cutting off both directions. This would knock Clementi, Dover, Buona Vista, Commonwealth off the grid. All 4 stations ceased services. Thousands of passengers would have to find alternative ways. At Buona Vista, Circle Line would still resume as it remains unaffected.

Are you going to put LRT line to every station? Say Clementi has LRT line, other three stations do not have LRT lines. How? Thousands of students would be stranded at Dover. So they have to walk all way to Buona Vista CCL? What about the ones at Commonwealth? They need to walk to Queenstown?

In this case, buses would be deployed to pick them up and send them to the next station. The best solution would be putting cross tracks at every station. So are you going to put LRT line to every station? All of these 4 stations? Are your LRT proposed trains going to be like Kelang Jaya or Bukit Panjang LRT trains?

Bukit Panjang LRT was conceived to feed into the main line. This was LTA's vision. What the LTA planners did not realise, many residents still prefer to take direct buses out of Bukit Panjang - SMRT 190, 700 and 960 to city centre, instead of taking trains. Furthermore there are alot of bus services that can take them out of BP to other area. It is much faster to reach Jurong via SMRT 180. The limitation of LRT is that it does not connect to other lines.

Downtown Line was already in the plans all the way. This was to relieve the congestion on the busy roads along the roads. No doubt this will impact the bus services directly because many bus services ply along the DTL largely. To get to Orchard, SMRT 190 can take you out of BP to Orchard via BKE and PIE in 30 minutes, depending on how fast the buses speed.

With this, LTA planners obviously change the track and put LRT plans on hold. They are starting to expand more on MRT lines. The major advantage is that buses can get you to bus stop next to your final destination.

I would prefer to have bus services to supplement to MRT/LRT lines. There are number of bus services that ply almost most of the MRT line.

For example, SBS 143 from Toa Payoh to Somerset. It may appear that it is slower to take bus but they can deliver you to the doorstep of your favourite mall. SBS 502 is popular with Jurong West/East residents because it takes passengers directly to bus stops outside their homes from Orchard area.

Expressways have alternative options and have numerous exits. When one section is affected, road traffic is diverted. Rail lines carry thousands of people who have no alternative options.
I'm proposing alternative route options.

For example, Jurong East-Redhill section. Queenstown and Jurong East have cross tracks. If there is train accident at Commonwealth, cutting off both directions. This would knock Clementi, Dover, Buona Vista, Commonwealth off the grid. All 4 stations ceased services. Thousands of passengers would have to find alternative ways. At Buona Vista, Circle Line would still resume as it remains unaffected.
If there were, for example, LRT lines running from Kent Ridge to NUS to Dover to Sixth Avenue, from Labrador Park to Commonwealth to Holland Village to Sixth Avenue, from Kent Ridge to Queenstown to Orchard Road, etc., (all with other stops along the way), then commuters could bypass a problem at Commonwealth without resorting to buses.

Are you going to put LRT line to every station?
Yes, I would connect at least one and typically multiple underground LRT lines to every MRT station.

The best solution would be putting cross tracks at every station. So are you going to put LRT line to every station? All of these 4 stations?
Yes, I would, eventually.

Are your LRT proposed trains going to be like Kelang Jaya or Bukit Panjang LRT trains?
Depends on the load.

Bukit Panjang LRT was conceived to feed into the main line. This was LTA's vision. What the LTA planners did not realise, many residents still prefer to take direct buses out of Bukit Panjang - SMRT 190, 700 and 960 to city centre, instead of taking trains. Furthermore there are alot of bus services that can take them out of BP to other area. It is much faster to reach Jurong via SMRT 180.
Yes, and the commuters are rational in making these choices. LRT as previously implemented is too limited.

The limitation of LRT is that it does not connect to other lines.
Yes, agreed, exactly! That is why ddes and I have both suggested that these proposed underground LRT lines should be longer and connect multiple MRT lines.

Downtown Line was already in the plans all the way. This was to relieve the congestion on the busy roads along the roads. No doubt this will impact the bus services directly because many bus services ply along the DTL largely. To get to Orchard, SMRT 190 can take you out of BP to Orchard via BKE and PIE in 30 minutes, depending on how fast the buses speed.
Right, the DTL2 will eliminate the need and demand for some of the buses now serving Bukit Panjang, but not all of them. Specifically, DTL2 should be able to eliminate the need for buses 75, 176, 190, 700, 700A, and 970. Buses 160, 178, 180, 187, 307, 920, 922, 975, and 985 are likely to be unaffected by the DTL2. Buses 67, 170, 171, 177, 184, 960, 961, 961C, 963, 963E, and 966 are likely to be rerouted and consolidated. Further progress in eliminating the need for buses in the Bukit Panjang area could be accomplished by extending the DTL2 to Woodlands or by providing more complete LRT coverage or both.

With this, LTA planners obviously change the track and put LRT plans on hold. They are starting to expand more on MRT lines.
Rightly so. The early experiments with LRT produced disappointing results. As we agreed above, the main problem was that they did not interconnect multiple MRT lines.

The major advantage is that buses can get you to bus stop next to your final destination.
I'll readily concede that it's not practicable to build 4500 LRT/MRT stations to replace our 4500 bus stops. I do believe we could have 1200 LRT/MRT stations with at least one within 400 meters of every common destination on the island. Perhaps jitney services would develop to interconnect the LRT stations and provide LRT-to-door service.

I would prefer to have bus services to supplement to MRT/LRT lines. There are number of bus services that ply almost most of the MRT line.

For example, SBS 143 from Toa Payoh to Somerset. It may appear that it is slower to take bus but they can deliver you to the doorstep of your favourite mall. SBS 502 is popular with Jurong West/East residents because it takes passengers directly to bus stops outside their homes from Orchard area.
Very true, but broad LRT coverage would also deliver you to the doorstep of your favourite mall. An LRT running under Orchard Road could have an exit connecting to the basement of every mall. No need to face the rain. :)

As for helicopter thing over expressways, you missed the important point - motorists have their own vehicles getting to their destinations. The problems are already resolved.

As for rail transport, thousands of people depend on trains which they have no control.

LRT really cannot deliver the passengers to the doorsteps. Bus stops can be spaced out as little as 200m apart. LRT stations have to be aligned accordingly to ensure to shorten the travelling time as these trains cannot skip the stations like buses.

Being underground, one has to spend money on heavy security - CCTVs at every corner to weed out any unwanted activities such as raping ladies and terrorist acts, compared to elevated ones. So much to our taxpayers.

While I'll accept LRTs can be used to a better effect than how Singapore is using them, I'm not going to agree with mcarling that it is the holy grail.

However, I think very few people can fully comprehend what a 280km rail network will really mean for Singapore and what it'll entail. Assuming that the rate of rail expansion continues in the current rate, I challenge people like jedialf to vision a Singapore in 2040. Perhaps that's difficult, but let's just narrow it down to the public transport network. I know for some, you might be dead by then, but a country's life is beyond any one person's life.

If the name "LRT" doesn't ring well with you, what about an medium-capacity "MRT" built in the style of Paris or Madrid's Metros; smaller cars, smaller stations, and overall cheaper to build than 3-car higher capacity "medium-capacity" CCL/DTL lines. LTA is envisioning a 400plus km or 500km (someone tell me the exact number), where do you think all those lines are going to fit in a 700sqkm land we know as Singapore?

And what of bus' roles? We don't have a huge population so if rail expansion is going to continue, what about buses?

Do you dare to dream of a Singapore where SBS Transit's bus operations is a quarter of its current size, where it'll focus its core operations on scheduled "charter" services to serve condo estates, premium services, private estates, feeder services and intra-town services like the 11x services?

2040? Each line needs at least 5 years to construct. From 2009 to 2020, two major lines (each 5 years of construction and 5 years of final planning) - TSL and ERL will be underway. If projects are overlapping in a row at this rate, it would need at least 4 major projects.

Well buses would be still around despite the growing rail infrastructure. Buses have been around since 1950s. Early form of bus went back to 1820. Already 189 years.

http://www.lightrailnow.org/images/saa-lrt-bus-saarbruecken-interchg-apr2003_s-baguette.jpg
Saarbruecken, Germany - bus service coexists with LRT.

Cool website - Paris - Bus line no 38 created by bus drivers (http://bus38.online.fr/indexeng.html)

It also has map of massive Paris. It becomes excellent transport for people to see the city streets as buses go past.

As for helicopter thing over expressways, you missed the important point
I apologize for the hyperbolic comment about the helicopters. My point was that the odds of several MRT lines failing at the same time is so remote that your argument was a straw man. Anything that could close several MRT lines simultaneously (such as a major earthquake) would also close several expressways and many other roads. I hope I explained satisfactorily how my proposal would address your excellent question about the consequences of a bi-directional stoppage at Commonwealth.

LRT really cannot deliver the passengers to the doorsteps. Bus stops can be spaced out as little as 200m apart.
Yes, I've already acknowledged that LRT stations cannot be as numerous (4500) or as closely spaced as bus stops. I'm not aware of any off-grade rail systems with interstation spacing closer than about 500 meters. We know that 500 meter interstation spacing can work well. Anything tighter than that would be a great leap into the unknown and I'm not suggesting it.

LRT stations have to be aligned accordingly to ensure to shorten the travelling time as these trains cannot skip the stations like buses.
Buses suffer the same constraint of having to ply routes aligned to shorten travel times. Buses are further constrained by having to follow roads, whereas underground LRT lines can in many cases cut along straighter paths.

Being underground, one has to spend money on heavy security - CCTVs at every corner to weed out any unwanted activities such as raping ladies and terrorist acts, compared to elevated ones. So much to our taxpayers.
I disagree. Elevated stations still need CCTV and patrol security. Women (and sometimes children and even men) have been raped at elevated rail stations. An elevated station may be a more attractive target for terrorists than an underground station because the damage is more visible and terrorists raise money from their donors by showing dramatic photos and videos of their misdeeds.

While I'll accept LRTs can be used to a better effect than how Singapore is using them, I'm not going to agree with mcarling that it is the holy grail.
I'm not suggesting that underground LRT is a holy grail. I'm suggesting that the concept is worthy of serious consideration by LTA.

I think very few people can fully comprehend what a 280km rail network will really mean for Singapore and what it'll entail. Assuming that the rate of rail expansion continues in the current rate, I challenge people like jedialf to vision a Singapore in 2040. Perhaps that's difficult, but let's just narrow it down to the public transport network. I know for some, you might be dead by then, but a country's life is beyond any one person's life.

If the name "LRT" doesn't ring well with you, what about an medium-capacity "MRT" built in the style of Paris or Madrid's Metros; smaller cars, smaller stations, and overall cheaper to build than 3-car higher capacity "medium-capacity" CCL/DTL lines. LTA is envisioning a 400plus km or 500km (someone tell me the exact number), where do you think all those lines are going to fit in a 700sqkm land we know as Singapore?
LTA said 540 kilometers by 2030. I can envision the 278 kilometers planned by 2020. I have much more difficulty envisioning the 540 kilometers planned for 2030. I can see two possibilities. LTA can either
- continue building new lines on the scale of the DTL, TSL, and ERL parallel to existing lines to bring commuters directly into the CBD (or to interchange to another such outbound line via the CCL) by building, for example, a line between the EWL and DTL3, or
- start building underground light rail to interconnect the MRT lines and provide local service with 400 meter coverage.
I just don't see any other way to get to 540 kilometers. If anyone has alternative ideas on how to get to 540 kilometers of rail by 2030, I'm very interested to read them.

The interesting challenge from ddes to envision public transit in Singapore in 2040 is daunting. We have no guidance (of which I'm aware) from LTA beyond the 540 kilometer goal for 2030. Even thinking about the approximately 262 kilometers of rail to be added during the 2020s is a challenge. I think the Holland, Seletar, and North Shore lines are highly likely, but we can account for about 25 kilometers for the Holland Line, 18 kilometers for the Seletar Line, and at most 27 kilometers for the North Shore Line (assuming it goes all the way to Woodlands station). That's only about 70 kilometers with another approximately 192 left unaccounted for.

Would LTA continue building at that pace? Maybe. Would they slow the pace as the rail system matures? Maybe. Would they declare the system completed and stop altogether? I very much doubt that. Mature metro systems like London, Paris, and Moscow are still building new lines.

And what of bus' roles? We don't have a huge population so if rail expansion is going to continue, what about buses?
If rail expansion continues at the pace planned for the next decade, then bus services will continue to be reduced, not only relative to rail services but in absolute terms. Daily rail ridership recently passed upwards of 1.5M while daily bus ridership has remained fairly steady at just below 3M. With the pace of rail construction over the next decade at least double what it's been in the past, I think we'll see the number of daily bus trip fall to about 2M by 2020, at which time the number of rail trips will exceed 4M per day. If we reach the goal of 540 kilometers of rail, then I expect the number of daily bus trips will fall below 1M per day.

To obviate the need for daytime buses completely would, in my opinion, require at least 1000 kilometers of rail with at least 1200 stations. Even then jitney services would probably be needed. I think the odds of getting there by 2050 are very small, but not quite zero.

Do you dare to dream of a Singapore where SBS Transit's bus operations is a quarter of its current size, where it'll focus its core operations on scheduled "charter" services to serve condo estates, premium services, private estates, feeder services and intra-town services like the 11x services?
"He who dares wins." -- slogan of the 22nd SAS regiment.

From 2009 to 2020, two major lines (each 5 years of construction and 5 years of final planning) - TSL and ERL will be underway.
Don't forget the DTL!!! It takes about five years from the time the construction contracts are signed until the line opens, but there are years of planning prior to that. I think the minimum time from conception to operation is probably ten years. New lines are starting the planning and tendering process with an interval of about two years. At that rate, we should expect about five new lines per decade. Even that rate doesn't even approach what would be required to go from 278 kilometers to 540 kilometers during the 2020s.

Well buses would be still around despite the growing rail infrastructure.
Certainly, in 2020 with 278 kilometers of rail, buses will still be needed, but they will be substantially reduced from what we have today. Even in 2030, with a projected 540 kilometers of rail, buses will be needed, but just a fraction of what we have today.

The probability of simultaneous failure of several rail lines is about as likely as the simultaneous collapse of several expressways.
No, all it needs is a failure of Singapore's power grid, or somebody calling 999 and saying that there's a bomb in a train that will detonate in 15 minutes. (Or, if you really want to disrupt things, an actual explosion.)

Singapore will need buses for at least another 50 years, but the dependency can be reduced over time and eventually eliminated (except for night buses).
Sorry, there's not a single city in the world which doesn't have bus services. Tokyo has what is almost certainly the world's densest train network, with every mode of rail transport known to man (heavy rail, subway, at-grade tram, elevated APM, monorail, bullet train, ...) yet it still operates an extensive fleet of feeder buses, even in city center areas crisscrossed by dense webs of train lines. Simply put, it's not possible to build direct lines between every combination of points, and a bus directly from point A to point B is faster and more comfortable than trains from A to B with transfers at C, D and E.

No, all it needs is a failure of Singapore's power grid, or somebody calling 999 and saying that there's a bomb in a train that will detonate in 15 minutes. (Or, if you really want to disrupt things, an actual explosion.)
Good point about a power grid failure, though the chances are remote. Of course, a failure of the power grid on that scale would obviate the need to get to work on time as few workers are productive without electricity. Bomb threats and actual explosions can close expressways as well as rail lines.

Sorry, there's not a single city in the world which doesn't have bus services. Tokyo has what is almost certainly the world's densest train network, with every mode of rail transport known to man (heavy rail, subway, at-grade tram, elevated APM, monorail, bullet train, ...) yet it still operates an extensive fleet of feeder buses, even in city center areas crisscrossed by dense webs of train lines. Simply put, it's not possible to build direct lines between every combination of points, and a bus directly from point A to point B is faster and more comfortable than trains from A to B with transfers at C, D and E.
Tokyo has 882 rail stations in a city of 2187 square kilometers. Paris has 245 stations in 105 square kilometers (less than 100 inhabited square kilometers, not counting the two large parks). Despite already having a rail density six times higher than that of Tokyo, Paris is continuing to build new metro lines to further reduce their dependency on buses.

I figure Singapore has about 300 square kilometers that are now or are planned to be residential or commercial and perhaps 200 square kilometers that are industrial. It's clear from the experience in Paris that to obviate the need for buses, a rail density higher than 2.5 stations per square kilometer would be needed. 3.5 stations per square kilometer in residential areas, 6 per square kilometer in commercial areas, and 2 per square kilometer in industrial areas might suffice. That would be about 1200 stations in Singapore.

We don't know exactly the rail density which would obviate the need for buses, but we can confidently say that it would be somewhere above 1000 stations. Since there are 4500 bus stops in Singapore and a rail station can in most cases directly replace two bus stops (on opposite sides of a street), the upper bound is 2250. My guess is that the actual number needed would be between 1000 and 1500 stations.

Is it plausible for Singapore to someday have more than 1000 rail stations? Yes, but not elevated stations, not predominantly the relatively heavy rail lines of the current and planned MRT and probably not before 2050 or 2060. A network of 50 or so light underground lines with a capacity in the range between our LRT and the lighter Paris metro lines would do the job. A few more heavy MRT lines like the Holland and Seletar lines would also be needed to get people into the CBD.

In the past and the present, this was cost prohibitive. However, tunnel-boring costs continue to drop, land becomes increasingly valuable, and above-grade construction becomes more expensive. We seem to be headed toward economic viability for such an undertaking.

I ask again: How do others envision the planned construction of about 262 kilometers of new rail lines during the 2020s to reach the announced goal of 540 kilometers by 2030? What would those lines look like?

i think CCL is very much like an underground light rail.
in malaysia/thailand/japan/korea this is already like a light rail system eg. kelana jaya or ampang line.

to be honest i find the LRT very impractical and an eyesore.

^^ CCL with only stage 3 in operation seems like an LRT. But in actual, when the entire line is in operation, will seem more like an MRT line I'm sure. Currently, its catchment area is severely limited to 3 new areas and 2 existing. While it is enhancing connectivity and cutting down time (eg. faster to Bishan from Dover by 74 and CCL), it will take a few years before the full effects are felt. Think of all the SMU students who will take the train to town in time to come.

Bomb threats and actual explosions can close expressways as well as rail lines.
Really? How would you even go about "closing" expressways if somebody called in to say "there's a bomb on a car somewhere in Singapore"?

Tokyo has 882 rail stations in a city of 2187 square kilometers. Paris has 245 stations in 105 square kilometers (less than 100 inhabited square kilometers, not counting the two large parks).
You're making the common mistake of confusing Tokyo Prefecture with the actual city. The central 23-ku covers only 621.9 sq.km, and this area is served by 102 train lines with 910 stations. Tokyo has an estimated 20 million daily rail commuters, compared to around 4.5 million for Paris.

Also, where did you get your earlier figures for bus transport in Paris? In 2004, RATP buses (http://en.wikipedia.org/wiki/Bus_(RATP)) had 953.6 million pax, or ~2.5 million/daily -- over half the metro volume. By comparison, Toei Bus (http://en.wikipedia.org/wiki/Toei_Bus#cite_note-Toei_Bus-0), the only bus operator in central Tokyo, only had 568,863 rides/day in 2005.

to be honest i find the LRT very impractical and an eyesore.
When the LRT was first built, I thought it was cool and futuristic. Every year it becomes more of an eyesore. I dread the idea of Singapore covered by elevated LRT (or MRT) lines.

^^ CCL with only stage 3 in operation seems like an LRT. But in actual, when the entire line is in operation, will seem more like an MRT line I'm sure. Currently, its catchment area is severely limited to 3 new areas and 2 existing. While it is enhancing connectivity and cutting down time (eg. faster to Bishan from Dover by 74 and CCL), it will take a few years before the full effects are felt. Think of all the SMU students who will take the train to town in time to come.
I agree. I cannot see how all of the approximately 262 kilometers of rail planned for opening during the 2020s can be as heavy as the CCL.

Really? How would you even go about "closing" expressways if somebody called in to say "there's a bomb on a car somewhere in Singapore"?
I'm not going to post information here that might be useful to either a real terrorist or a hooligan prankster.

You're making the common mistake of confusing Tokyo Prefecture with the actual city. The central 23-ku covers only 621.9 sq.km, and this area is served by 102 train lines with 910 stations. Tokyo has an estimated 20 million daily rail commuters, compared to around 4.5 million for Paris.
I got my numbers for Tokyo from Wikipedia. It's possible that they may be wrong in the way that you suggest or I may be misinterpreting the information.

Also, where did you get your earlier figures for bus transport in Paris? In 2004, RATP buses (http://en.wikipedia.org/wiki/Bus_(RATP)) had 953.6 million pax, or ~2.5 million/daily -- over half the metro volume. By comparison, Toei Bus (http://en.wikipedia.org/wiki/Toei_Bus#cite_note-Toei_Bus-0), the only bus operator in central Tokyo, only had 568,863 rides/day in 2005.
In the case of Paris, you're making exactly the mistake which you accuse me of making for Tokyo. Only 35% of the Paris bus trips you cite are in the city. The other 65% are suburban trips outside of Paris. It's even explicitly segregated in the Wikipedia citation you provided.

I think the argument of possible simultaneous disruptions is irrelevant. By 2020, if the DTL/ERL/TSL/CCL/EWL/NEL/NSL, a total of 7 lines are designed what they are designed to do, it will already result in a certain downsizing of bus operations already. The city is a living and breathing organism that depends on all parts to work. If a life-stopping event such as a terrorist threat or a failure of the power grid would happen, I can tell you that the city will temporarily cease functioning until those problems are solved. Remember the loss of power grid to the NE of the US a few years back? Noone is saying "Oh, we should have bought more buses so we could get people out of Manhattan".

This thread doesn't really ask you to compare buses versus medium/light-rail transit. It challenges you transport enthusiasts to plan our rail infrastructure beyond what we are already spoon-fed by LTA. This thread is saying we have a limited population and we can't keep building 6-car lines anymore, even 3-car lines is starting to appear abit much. However, a step under 3-car lines isn't our 2-car Bukit Panjang LRT stock, it's Paris Metro's lighter stock, it's Taipei's Muzha Line, it's the Vancouver SkyTrain, it's the Kelana Jaya Line.

I know some will say how can we people plan rail lines since we're not LTA? Honestly, even after the ERL/TSL/DTL is completed, our network hasn't reached the level where the major corridors are served and we don't need a government agency to figure that out although I'll admit that the DTL knot is rather ingenious.

Regarding the rail density, I suggest not comparing with Tokyo because figures for Tokyo(the city) is debatable and figures are more from Tokyo(the megalopolis). Anyway, if I remember correctly, the LTA has NEVER mentioned that it is intended to reach the rail density of Paris for Singapore. It has always been London, Tokyo, New York. So to benchmark the "future" as Paris' Metro may be abit misguided. However, I think it isn't unreasonable to reach Paris Metro's rail density within the Circle Line. Outside that, rail expansion may be slightly more conservative.

ddes, thank you for your very thoughtful contributions to this thread and helping to keep it on track.

It's really not at all obvious to me how the LTA envision 540 kilometers by 2030. I haven't seen any plausible suggestions other than what you and I have been suggesting.

I'm really very interested in what others expect might be built during the 2020s (and beyond). I'm skeptical about another approximately 262 kilometers of CCL/DTL/TSL/ERL size lines being built during the 2020s. I can imagine 25 kilometers for the Holland Line, 18 kilometers for the Seletar Line, perhaps as many as 27 kilometers for the North Shore Line, and 8 kilometers to extend DTL2 to Woodlands. That's about 78 kilometers. Where would the other approximately 184 kilometers run? Where else could LTA put CCL/DTL/TSL/ERL type trains on a massive scale? The only thing I can think of is to run new parallel lines between existing lines, for example, between DTL3 and EWL (under the PIE) from the CBD out to Tampines or Changi. Maybe <1 kilometer spacing between parallel MRT lines is the best approach?

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You know what? I'm going to suggest the North Shore Line's length be revised as high as 35km. Why? Firstly, the fact that the Sembawang station was shifted southwards to its current position means that the original NSL was to serve as north as into the Senoko industrial estate. Shifting the line south has now necessitated the need to extend the North Shore Line to serve the Senoko/Woodlands industrial estates which has proven better in the long term because a majority of the workers are Malaysian so a fork to the Checkpoint may improve the commute for them. On the eastern end, it could be pulled as far east as into Changi East to either possibly interchange with either the ERL at Changi or a parallel CGL to T4, through to the Changi East when reclamation ends, or possible bend into Tekong too.

Beyond the North Shore, Seletar and Holland Lines?

Well, I think there will be a need for a West Coast Line/South West Line, the speculated NEL extension. The Concept Plan clearly shows an MRT line besides the 2 EWL forks running into the west and along with Jurong Island.

Since I've pushed the North Shore Line as close to the shore as possible, it will also not provide a good replacement for the north/central to east buses that largely run on the TPE or parallel to it. That's where I believe there will be a need for an AMK-Hougang-Tampines/Bedok line. This will not eat into the CCL traffic because this line will largely serve the high traffic corridor of AMK-Hougang, Hougang-Tampines/Bedok of AMK Ave 3/Hougang Ave 2/3. There are just too many double-deck buses running along this corridor to keep it operating as buses, just far too many.

Jurong Region Line/Western Region Line. If the Jurong Lake development takes off as planned, Jurong East Central will be a proper CBD district of it's own and thus will need lines to radiate into it. The Boon Lay-Bukit Batok West-CCK/BP corridor, the Bukit Timah DTL/Clementi/Ngee Ann Poly/SIM corridor will be essential.

Likewise with the Expo and CBP area but I'm not too confident on that getting more lines because of the existence of the EWL, DTL, CGL and ERL.

You know what? I'm going to suggest the North Shore Line's length be revised as high as 35km. Why? Firstly, the fact that the Sembawang station was shifted southwards to its current position means that the original NSL was to serve as north as into the Senoko industrial estate. Shifting the line south has now necessitated the need to extend the North Shore Line to serve the Senoko/Woodlands industrial estates which has proven better in the long term because a majority of the workers are Malaysian so a fork to the Checkpoint may improve the commute for them. On the eastern end, it could be pulled as far east as into Changi East to either possibly interchange with either the ERL at Changi or a parallel CGL to T4, through to the Changi East when reclamation ends, or possible bend into Tekong too.
If the eastern terminus of the North Shore Line is Changi T4 and the western terminus is either Woodlands MRT station or Woodlands Checkpoint, then I don't see how it could be longer than 30 kilometers. Are you think of 5 or so kilometers each of Changi T4?

Since I've pushed the North Shore Line as close to the shore as possible, it will also not provide a good replacement for the north/central to east buses that largely run on the TPE or parallel to it. That's where I believe there will be a need for an AMK-Hougang-Tampines/Bedok line. This will not eat into the CCL traffic because this line will largely serve the high traffic corridor of AMK-Hougang, Hougang-Tampines/Bedok of AMK Ave 3/Hougang Ave 2/3. There are just too many double-deck buses running along this corridor to keep it operating as buses, just far too many.
Yes, I agree that there are too many buses running along the TPE and nearby parallel roads. However, the CCL and North Shore Line will both serve to alleviate this -- to an extent which is as yet unknowable. I would wait to see how new traffic patterns emerge after completion of the CCL and North Shore Line before beginning construction of an AMK-Tampines line, though I think you're right that some such line needed. I just don't know whether it should be a 3-car CCL/DTL type line or a lighter line.

Jurong Region Line/Western Region Line. If the Jurong Lake development takes off as planned, Jurong East Central will be a proper CBD district of it's own and thus will need lines to radiate into it. The Boon Lay-Bukit Batok West-CCK/BP corridor, the Bukit Timah DTL/Clementi/Ngee Ann Poly/SIM corridor will be essential.
I think this is a good example of where the sort of lighter line with closer interstation spacing that we've been proposing would be a great fit. For example, a lightweight Boon Lay to Chao Chu Kang would give the Holland Line a great place to terminate without a need to split.

Likewise with the Expo and CBP area but I'm not too confident on that getting more lines because of the existence of the EWL, DTL, CGL and ERL.
CGL???

Sorry, I dislike to "quote" but I'll answer your comments chronologically.

I'm looking at the North Shore Line to go as far west as the Woodlands Water Fab/Kranji Way area, plus a fork into Woodlands MRT. This is to allow the North Shore Line to stable trains at the DTL's Woodlands depot. And yes, this is assuming a DTL extension northwards. The eastern end depends on the ERL. Assuming the ERL goes through Changi Airport EWL and terminates somewhere near Changi Ferry Terminal, then I'd pull the North Shore Line into Loyang, Changi Village, Changi Ferry Terminal and east along the northern coast of Changi East instead of directly east into Changi Airport.

CGL = Changi Airport extension of the EWL which I suspect, could be a hybrid branch line of the EWL as well as a real line that'll serve Changi East and towards Tekong in future.

^^
I think the area from Kranji Way to the Woodlands Checkpoint might be better served by a very light line. I could envision the North Shore Line terminating at Woodland Checkpoint with a station that interchanges with the TSL.

I would run a DTL2 extension between Mandai Estate and Mandai Training Village, south of the Turf Club, past the Singapore American School to terminate at Woodlands Station.

Your ideas for the Changi area make sense to me. How many daily passengers use the Changi Ferry Terminal?

^^ Not going to dispute your suggestions but I don't think the DTL2 should interchange with Woodlands. Maybe Marsiling or Kranji.

Haha. I don't think many use Changi Ferry Terminal but I suspect there's still quite a number. My intention is to connect passengers to the Changi Cargo Complex which appears to have many people working there considering that there are 2 services which run mostly double-decked services to the area, as well as the SAF Ferry Terminal for obvious reasons.

I would keep the DTL2 inside the NSL and interchange at Woodlands station because fast service along the high-traffic corridors is important. There are 11 different bus lines running between Bukit Panjang and Woodlands. A more direct route for DTL2 might cut ten minutes off every trip compared to a meandering route outside the NSL. Ten minutes, twice a day, times tens of thousands of passengers adds up to a big deal. The areas outside the NSL would, in my opinion, be better served by lighter underground lines of the sort this thread has been discussing.

I see your point about the Changi Cargo Complex. May I suggest locating a station right outside the main entrance of the Changi Cargo Complex which would also conveniently serve the SAF Changi Ferry Terminal and the Changi Exhibition Centre? That's about 1600 meters from the Changi Ferry Terminal.

I would keep the DTL2 inside the NSL and interchange at Woodlands station because fast service along the high-traffic corridors is important. There are 11 different bus lines running between Bukit Panjang and Woodlands.The areas outside the NSL would, in my opinion, be better served by lighter underground lines of the sort this thread has been discussing.

May I suggest locating a station right outside the main entrance of the Changi Cargo Complex...

I'm suggesting DTL2 interchange with either Kranji or Marsiling rather than Woodlands station because I'd imagine the TSL might bring a rail density to the Woodlands "south of the NSL" which might be close to the city's and honestly, we don't need that.

That's fine too.

I'm suggesting DTL2 interchange with either Kranji or Marsiling rather than Woodlands station because I'd imagine the TSL might bring a rail density to the Woodlands "south of the NSL" which might be close to the city's and honestly, we don't need that.

I'm suggesting a more direct route for a DTL2 extension because there are now 11 bus services between Bukit Panjang and Woodlands. The TSL will not help alleviate that demand.

I would be happy to see more rail connections into Jurong, Woodlands, and Tampines. The current concentration in the CBD is, in my opinion, too intense. As various government ministries, agencies, and statutory boards need to move into new buildings, I'd like to see them move out of the CBD into Jurong, Woodlands, and Tampines. That would allow more people to live nearer to their places of work and would mean more people would have reverse commutes (without crowds).

I'm not saying that the TSL will alleviate demand. Metro lines have to decently serve the places they're running along, so even a DTL2 extension must bring some benefit to commuters living within Woodlands itself.

I just feel that a hypothetical DTL2 extension into Sungei Kadut or Kranji or through to the Woodlands checkpoint interchanging with a hypothetical TSL Woodlands checkpoint station will yield more benefits instead.

Metro lines have to decently serve the places they're running along, so even a DTL2 extension must bring some benefit to commuters living within Woodlands itself.
I agree 100%. I imagine that some of the people now using those 11 different bus services running between Woodlands and Bukit Panjang are Woodlands area residents. However, regardless of the direction of their commute, getting most of them off the buses and onto trains would be a good thing.

I just feel that a hypothetical DTL2 extension into Sungei Kadut or Kranji or through to the Woodlands checkpoint interchanging with a hypothetical TSL Woodlands checkpoint station will yield more benefits instead.
Maybe. In the short-term, I would prefer to see feeder buses running along routes roughly perpendicular to the NSL and DTL2, to eventually be replaced by underground LRT lines.