Tunnelling has begun on the $8.3 billion North-West Rail Link, the largest public transport project in the country.

At a ceremony in Bella Vista in north-west Sydney on Monday, Premier Mike Baird and Transport Minister Gladys Berejiklian marked the start of work on 15 kilometres of twin tunnels, the longest ever built in Australia.

The start of tunnelling fulfils an election promise by the government to have machines in the ground in 2014. However, it also means that the controversial decision to build the tunnels too small to ever run double-decker trains is now locked in.

finally making some progress.  when is the project scheduled for completiuon?

finally making some progress. when is the project scheduled for completiuon?

2019 (i think the govt said that some time ago) + whatever it takes to stop it from being white elephant. (fk those tunnels are too small)

2019 (i think the govt said that some time ago) + whatever it takes to stop it from being white elephant. (fk those tunnels are too small)

It won't be a white elephant at all, look at the report on where NW commuters actually travel to.  

Nothing to do with the tunnel size. Cityrail's operating costs are too high to continue the current path. Time for something new and more standardised. Sooner and not much later there will need to be another harbor crossing and NWRL technology into the south side makes sense. This enables the NSL to carry more traffic from further away.

I could reluctantly accept the inevitable progression of the North West Rapid Transit concept across the harbour, despite its inappropriateness for what is essentially a low density outer suburban corridor (just like the South West Rail Link), if it were to remain a completely separate system without bastardising Sydney's existing rail network, ie, converting the existing Bankstown Line and possibly Illawarra Local Line to Hurstville.  This would require the new Rapid Transit cross harbour link to connect with the previously proposed West Metro to Parramatta/Westmead via Barangaroo and the Metro West rail corridor through the CBD.  An alternative would be to connect with a South East Metro to Maroubra Junction/Malabar via the Pitt St corridor, although probably less likely now that the light rail is proceeding.

This is a black day for Sydney rail network planning, because it is a political decision to sideline Sydney Trains and to begin privatisation of the network and not an objective assessment of the needs of the greater rail network, which will continue to be the dominant sector for many years to come.  Despite the government's misleading assertion that extension of the Rapid Transit concept will increase train services through the CBD by 60%, it is predominantly via a new rail line and does absolutely nothing to enhance the capacity of the existing rail network, which is the most in need.  The most congested part of the Sydney Trains network is between Strathfield and the CBD and in the future from the south west via the East Hills Line.  Sooner or later this is going to have to be addressed IN ADDITION to any new Rapid Transit cross harbour link.  

A disappointing aspect of this whole farce is that the new Sydney Trains CEO, Howard Collins, not long after his appointment, had expressed the view that he was quite impressed with Sydney's double deck trains, travelling on them every day to work, but it appears he has since been muffled and now tows the government's line.

The DD's do a good job, but they are best used for longer runs than shorter. The other issue is that the whole technology in Sydney is do damn expensive to operate for the people they move. Things need to change and the SWRL is basically the line in the sand, move to something more off the shelf and more compatible with other networks. Germany doesn't run DD's on inner suburban, metro services. Yes the NWRL is a long line by some standards as a Automated Metro, but Dubai runs a 50km long Red line 100% automated, others will follow.


The match up with the Hurtsville/Bankstown is a natural fit. It has to go somewhere and this is logical as there is no freight or interurban and country services. The platforms are probably well suited to trains with mid car doors (I did a google check on some of the route).


I'm sure there is a bigger picture to the NWRL extension into the southern side and helping the Inner West capacity. I think in the future (assuming above happens),


- The local pair of tracks from Redfern to Hombush claimed by a automated Metro service which will have its own route to Lidcombe built to complete the Bankstown loop. This is called the Inner West Metro.
(They may go cheap and stop it at Homebush, or maybe the loop via the Olympic Park for both)


- The West DD's Services will have a number of stops removed and operate limited express from Lidcombe to City, option of changing to an Express at 2-3 stations only.


- With Bankstown out there is more track capacity for the Loop tunnels to increase trains from the west, but its still not perfect. Removal of the inner west locals fully clears the city circle pair of tunnels. In theory the limitation for the inner west is now the four tracks from Straithfield to Central.


- The Middle pair of tracks which effectively run from Granville could run 20t/hr to the City and then across the bridge
- The Nth pair from Granville to Straithfield could be for interurban, country and outer western/South Western expresses, probably maxing out at 12t/hr and then there is capacity to take say 4 trains per hour from Hornsby and 4 trains per hour from Gosford/Newcastle. However they all need to have a similar stopping pattern, which is buggerall for the northern tracks anyway, but it would be standardised. IU run into Central Terminal and suburaban run into former Bankstown/Inner West tunnels.


While there is a bit of work to make the above work (and I'm sure it won't be as I wrote above, but just to give an idea), its not a huge project and really there is no advantage in starting until the Metro is built to clear the paths.

I emphatically disagree RTT_Rules with your synopsis.  The alleged excessive dwell times for DD stock is only a problem at 3 stations on the whole Sydney Trains network (Central, Town Hall and Wynyard) and it can be managed.  A new cross harbour and CBD rail link with modern station design and upgraded signalling will benefit both single deck rapid transit AND DD operation.  Proponents of RT conveniently neglect to make valid comparisons with DD operation by making misleading claims about the relative merits of each system in comparing RT operation on a new line with DD operation on the existing network.  DD operation on a new CBD link, with modern station design and improved signalling, could match the frequency of RT and even exceed RT's passenger carrying capacity depending on its ratio of seating to standing.  DD can also have Automatic Train Operation.  

I don't know about the situation in Germany and I presume you're referring to Berlin, but the Paris RER (as distinct from the Paris Metro) and which is considered to be the closest equivalent to the Sydney Trains network, has DD trains running through the city centre up to 30 tph.  They are currently replacing their single deck stock with new state of the art DD.  It's a similar situation in Zurich and an increasing number of European cities are introducing DD trains on their suburban railways into the city centre to increase their passenger carrying capacity.  We're doing the reverse.  I don't think the situation in Dubai is relevant to Sydney.

The Inner West Local line from Central to Homebush is the most logical extension for the RT concept if it proceeds, but it was discarded because of the difficulty of connecting it with the new CBD link at Eveleigh.  So Plan "B", connecting to the Bankstown Line and Hurstville via the Illawarra Local, was selected.  Contrary to your assertion that there is no freight or country passenger services on this line, freight trains from the Western and Northern Lines bound for the South Coast utilise the Illawarra Local from the Metropolitan Goods Line at Marrickville and will continue to do so until the Maldon to Dombarton rail link is built, but this is by no means certain.  Southern Region NSW Trainlink services to the Southern Highlands and Melbourne now use the East Hills Line via the Illawarra Local which is more direct than the previous route via Strathfield and Liverpool.  If they were denied access, these services would have to divert to the old route, or even via Granville if the route via Regents Park was converted to rapid transit.

Redirecting Western and/or Northern Line services to the City Circle is a poor option as it would compromise the concept of sectorisation, which after considerable expense, has improved the operational efficiency of the CityRail/Sydney Trains network.  It would be a backward step to throw this out the window.

I don't object to creating a completely separate rapid transit system for Sydney, but restricted to the inner city, say within a radius of 15 to 20 km from the CBD, which is what is typical by world standards for such a system.  I'm not in favour of confiscating parts of the existing suburban network and in the process compromising its efficient operation as a means by which a rapid transit/metro system can be created on the cheap.  I'm not aware if this strategy has been attempted anywhere else in the world.

I emphatically disagree RTT_Rules with your synopsis. The alleged excessive dwell times for DD stock is only a problem at 3 stations on the whole Sydney Trains network (Central, Town Hall and Wynyard) and it can be managed. A new cross harbour and CBD rail link with modern station design and upgraded signalling will benefit both single deck rapid transit AND DD operation. Proponents of RT conveniently neglect to make valid comparisons with DD operation by making misleading claims about the relative merits of each system in comparing RT operation on a new line with DD operation on the existing network. DD operation on a new CBD link, with modern station design and improved signalling, could match the frequency of RT and even exceed RT's passenger carrying capacity depending on its ratio of seating to standing. DD can also have Automatic Train Operation.

I don't know about the situation in Germany and I presume you're referring to Berlin, but the Paris RER (as distinct from the Paris Metro) and which is considered to be the closest equivalent to the Sydney Trains network, has DD trains running through the city centre up to 30 tph. They are currently replacing their single deck stock with new state of the art DD. It's a similar situation in Zurich and an increasing number of European cities are introducing DD trains on their suburban railways into the city centre to increase their passenger carrying capacity. We're doing the reverse. I don't think the situation in Dubai is relevant to Sydney.

The Inner West Local line from Central to Homebush is the most logical extension for the RT concept if it proceeds, but it was discarded because of the difficulty of connecting it with the new CBD link at Eveleigh. So Plan "B", connecting to the Bankstown Line and Hurstville via the Illawarra Local, was selected. Contrary to your assertion that there is no freight or country passenger services on this line, freight trains from the Western and Northern Lines bound for the South Coast utilise the Illawarra Local from the Metropolitan Goods Line at Marrickville and will continue to do so until the Maldon to Dombarton rail link is built, but this is by no means certain. Southern Region NSW Trainlink services to the Southern Highlands and Melbourne now use the East Hills Line via the Illawarra Local which is more direct than the previous route via Strathfield and Liverpool. If they were denied access, these services would have to divert to the old route, or even via Granville if the route via Regents Park was converted to rapid transit.

Redirecting Western and/or Northern Line services to the City Circle is a poor option as it would compromise the concept of sectorisation, which after considerable expense, has improved the operational efficiency of the CityRail/Sydney Trains network. It would be a backward step to throw this out the window.

I don't object to creating a completely separate rapid transit system for Sydney, but restricted to the inner city, say within a radius of 15 to 20 km from the CBD, which is what is typical by world standards for such a system. I'm not in favour of confiscating parts of the existing suburban network and in the process compromising its efficient operation as a means by which a rapid transit/metro system can be created on the cheap. I'm not aware if this strategy has been attempted anywhere else in the world.

I don't propose NWRL should be SD over DD or VV. Sydney's DD's type stock is limited on door number because the tightly curved platforms prevent mid car doors. Greenfield lines tend to have platforms built straight or very lightly curved and hence 3-4 door sets are viable and enables faster dwell times.

The issue is that you normally don't mix Fully Automated networks with Manual driven, hence they will be two seperate networks. The time for Cityrail add on's and being limited to improved 100year old technology is over. The NWRL is the start of the 2nd Sydney rail network which will be fully automated with its far lower operating costs and more flexible scheduling.

Any work that can be done on the city stations to speed them up and get more trains will most likely be done, but we are pushing the end of the envelope and a 2nd crossing needs to be done.

The Bankstown line won't be converted for at least a decade, by then freight will have been found or will be found a new path along with any other service that uses the route. There has been alot of money spent to seperate freight from suburban and there will be alot more to go.

The route through the city was an expample, yes it was against sectorisation which has more than proven its worth as well as proven why the NWRL doesn't have to be designed for the traditioonal rollingstock if there is something else available that is cheaper and I'm sure you could easily reword my above statement to return to the sectorisation. But the sectors we currently know may have to be re-distributed to get the best outcome of the new network.

Why is there a limit of 15-20km, what is this actually based on? Cities in Europe that are barely 30km across? Is km or time a factor ind eciding how far RT must run? What about the actual catchment and their destination? Systems like Germany and Paris are based on 60 year old Underground networks where interurban was surface because the cities are small in size but extremely expensive to build across the surface.  The U systems were expanded to enable surface rail to focus on longer haul. Dubai is one of the longer RT's and it will be built longer. Dubai and some other cities doesn't have a central CBD as such lke Sydney and hence the actual distance travelled is not centre fcused, just from where people live to where they work, which is scattered. A number of the RT's I have riden take over 1hr to go from terminus to CBD, mostly driven by slow alignment and number of stops.

Melbourne would be your first starting point for conversion from HR to RT and few would argue its sucess even though its a slower trip. Go back far enough Adelaide and then I suspose SLR?
The issue is "is the current system as efficent as it can be? In these forums a number of people have posted about the issues of the inner west, even the govt when they looked at using that for RT but were constrained by Everleigh, for now but its fixable. If conversion to RT gives a better service and opens up more capacity, do it. The DD's do an excellent job, but as the city has grown they are running out of capacity to move people to the city because the inner sections are inefficent due to contraints and bottle necks.

I agree running RT to the outer NW as a starter is a bit unsual, but it has to start somewhere and this may as well be it as extension to the city and new tunnels will be needed. The people movement map for the NWRL shows a large chunk don't travel to the city, so a bit like Dubai. Dubai is relevent because its similar in ways to the NW and also being brand new demonstrates what can be done when starting fresh and yes I am very familure with it.

I don't propose NWRL should be SD over DD or VV. Sydney's DD's type stock is limited on door number because the tightly curved platforms prevent mid car doors. Greenfield lines tend to have platforms built straight or very lightly curved and hence 3-4 door sets are viable and enables faster dwell times.

The issue is that you normally don't mix Fully Automated networks with Manual driven, hence they will be two seperate networks. The time for Cityrail add on's and being limited to improved 100year old technology is over. The NWRL is the start of the 2nd Sydney rail network which will be fully automated with its far lower operating costs and more flexible scheduling.

Any work that can be done on the city stations to speed them up and get more trains will most likely be done, but we are pushing the end of the envelope and a 2nd crossing needs to be done.

The Bankstown line won't be converted for at least a decade, by then freight will have been found or will be found a new path along with any other service that uses the route. There has been alot of money spent to seperate freight from suburban and there will be alot more to go.

The route through the city was an expample, yes it was against sectorisation which has more than proven its worth as well as proven why the NWRL doesn't have to be designed for the traditioonal rollingstock if there is something else available that is cheaper and I'm sure you could easily reword my above statement to return to the sectorisation. But the sectors we currently know may have to be re-distributed to get the best outcome of the new network.

Why is there a limit of 15-20km, what is this actually based on? Cities in Europe that are barely 30km across? Is km or time a factor ind eciding how far RT must run? What about the actual catchment and their destination? Systems like Germany and Paris are based on 60 year old Underground networks where interurban was surface because the cities are small in size but extremely expensive to build across the surface. The U systems were expanded to enable surface rail to focus on longer haul. Dubai is one of the longer RT's and it will be built longer. Dubai and some other cities doesn't have a central CBD as such lke Sydney and hence the actual distance travelled is not centre fcused, just from where people live to where they work, which is scattered. A number of the RT's I have riden take over 1hr to go from terminus to CBD, mostly driven by slow alignment and number of stops.

Melbourne would be your first starting point for conversion from HR to RT and few would argue its sucess even though its a slower trip. Go back far enough Adelaide and then I suspose SLR?
The issue is "is the current system as efficent as it can be? In these forums a number of people have posted about the issues of the inner west, even the govt when they looked at using that for RT but were constrained by Everleigh, for now but its fixable. If conversion to RT gives a better service and opens up more capacity, do it. The DD's do an excellent job, but as the city has grown they are running out of capacity to move people to the city because the inner sections are inefficent due to contraints and bottle necks.

I agree running RT to the outer NW as a starter is a bit unsual, but it has to start somewhere and this may as well be it as extension to the city and new tunnels will be needed. The people movement map for the NWRL shows a large chunk don't travel to the city, so a bit like Dubai. Dubai is relevent because its similar in ways to the NW and also being brand new demonstrates what can be done when starting fresh and yes I am very familure with it.

I accept that the NWRL Rapid Transit is now a fait accompli, literally set in concrete so to speak with the first TBM now in the ground, not that I agree with it.  So my attitude is to make the most of what we have before us and my preference would be to extend the rapid transit across the harbour to areas not currently served by a rail service, such as the West Metro to Olympic Park, Parramatta and Westmead in the corridor north of Parramatta Rd, rather than trying to convert parts of the existing Sydney Trains network.  The issue with me is not so much a preference of DD over SD, but an unrealistic attempt to convert a legacy suburban rail system into a modern automated rapid transit system, particularly where it compromises the overall efficiency of the broader rail network.

The existing Sydney Trains network may have its shortcomings and despite what you may think, it still provides a reasonably efficient service, but that doesn't mean it can't be improved upon.  You can't make comparisons between an extensive legacy suburban rail system and a new greenfield rapid transit/metro system in cities which haven't had the benefit of a large suburban rail network previously.  You don't throw the baby out with the bath water.  The Sydney Trains network could operate more efficiently if the politicians had the intestinal fortitude to address its shortcomings.  It's been done before in other jurisdictions (to quote Ron Christie).

The Sydney Trains network, thanks to the vision of Dr Bradfield, is already a hybrid suburban/metro system with trains continuing from the outer suburbs through the city centre.  There is no immediate need for an incompatible rapid transit/metro system.  The problem with the current system is not delays caused by dwell times at the major CBD stations, but the failure to provide additional track capacity through the CBD.  You can't just "fix" a large rail network like Sydney's by completely ignoring it and building something else.  The existing DD network, with additional upgraded track capacity through the CBD, could quite easily handle Sydney's rail traffic well into the future before any separate rapid transit system should even be considered.  The priority should be to continue upgrading the existing network with ATP and ATO.

There is an overemphasis on dwell times for DD stock at the major CBD stations (Central, Town Hall and Wynyard) on the existing lines, but very little acknowledgement of how this would not be an issue on a new line through the CBD.  There is no problem with dwell times for DD stock outside of the CBD, despite the government's rhetoric.  Outer suburban areas, including those on the NWRL, do not warrant a train service every 2 or 3 minutes.  Inner suburban stations with that level of service can adequately handle passenger flow because it is essentially one way, either getting on or getting off, depending on whether it's morning or evening peak.  The maximum train capacity of 30 tph through a new CBD spine, with modern station design, could also handle passenger flow without excessive dwell times for DD stock.  It would also take pressure off the existing CBD stations.  But it's all academic now.

Just as an aside, contrary to your assertion that a large chunk of commuters from the North West don't travel to the city, the overwhelming majority of buses from the North West currently travel direct to the city with minimal services to Macquarie Park, let alone to Chatswood and North Sydney.  A significant number do drive, because of the abundance of free parking, and that's unlikely to change even with the introduction of the NWRL.

Vote 1 Transtopic for Premier.

Perhaps related - I think there is an excessive focus at the moment on choosing a technology in terms of "passengers per hour".  That's not actually the real driver for a public transport system.  You don't just need people to get on and off your sets, you actually need to transport them some distance.  When you start looking at capacity versus likely demand for that line in terms of passenger-kilometres per hour I think the decision to go single deck looks very dubious.

(I don't subscribe to the rants that they had to go single deck in order to provide a clean break with all the industrial relations or whatever evils the legacy system currently entails - that's just ideological babble.  If that's what's motivating you then there are plenty, plenty, plenty of other options that force that break that don't entail infrastructure limitations that will be with you for the rest of time.)

If you are going to build additional near-inner-city lines (and we should, with additional city stations) absolutely build them to a smaller rolling stock profile (because you are going to be doing a lot of tunnelling...) and configure them so you can poke as many services per hour down them - all in classic "metro" style (and as you do that, the need to operate the DD lines as poor man's metros becomes less - so you can start to reconfigure them too).  But if you are going to be building new lines out in the boondocks (and with clear potential for the line to be extended much further to upper western outer boondock heights - FFS they are ALREADY seriously talking about the corridor heading south to Badgerys, let alone whereever else) it doesn't make sense to me.

Alas... too late now.

Vote 1 Transtopic for Premier.

Perhaps related - I think there is an excessive focus at the moment on choosing a technology in terms of "passengers per hour". That's not actually the real driver for a public transport system. You don't just need people to get on and off your sets, you actually need to transport them some distance. When you start looking at capacity versus likely demand for that line in terms of passenger-kilometres per hour I think the decision to go single deck looks very dubious.

(I don't subscribe to the rants that they had to go single deck in order to provide a clean break with all the industrial relations or whatever evils the legacy system currently entails - that's just ideological babble. If that's what's motivating you then there are plenty, plenty, plenty of other options that force that break that don't entail infrastructure limitations that will be with you for the rest of time.)

If you are going to build additional near-inner-city lines (and we should, with additional city stations) absolutely build them to a smaller rolling stock profile (because you are going to be doing a lot of tunnelling...) and configure them so you can poke as many services per hour down them - all in classic "metro" style (and as you do that, the need to operate the DD lines as poor man's metros becomes less - so you can start to reconfigure them too). But if you are going to be building new lines out in the boondocks (and with clear potential for the line to be extended much further to upper western outer boondock heights - FFS they are ALREADY seriously talking about the corridor heading south to Badgerys, let alone whereever else) it doesn't make sense to me.

Alas... too late now.

The terminology being thrown around I think is if anything confusing the issue, especially by the pollies as they have to manage the selling of this.

For my mind the reasons behind the NWRL are
- Its fully automated, hence significantly reduced lifetime operation costs. Its the way every other commuter line is being built where the opportunity is available. Really do we need to go much further why the current Cityrail network expansion is been drawn to an end? Nothing to do with union, its just what is happening everywhere when the option is available.

- Its off the shelf technology and hence lower CAPEX?

- Sydney has moved to sectoriation, so trains don't mix lines like they used to, the need for alternative corridors and paths is how the system operates now or the future. Trains operate A-B-A.  Due to peak hour congestion, if one line is blocked, often not much can be done anyway and with time even less.

- Sydney DD's stock has two doors because many stations have excessive curvature. The NWRL and the existing ECRL have straight to mostly straight platforms, hence multiple >2 door option rolling stock is an option that should be taken. Despite what many think the dwell time issue is not limited to 3 city stations. Its been a number of years since I commuted in Sydney, but Chatswood and numerous other stations I used to travel by also have slower dwell times. Cutting 5-10sec off per station along a line saves a few minutes per cycle which can be converted to less rolling stock.

- The current manually driven DD's with the best technology on offer will not exceed 2min through the city and its unlikely less than 2.5min is indeed practical. Greenfield automated RT's with more doors are doing 90sec.

History has shown that getting rolling stock supplied to Sydney involves custom made equipment due to its relatively unique profile. DD is far from unusual as its very common in Central Europe, but its not the same as there. Each contract has had numerous issues and costs per seat are probably way above standard equipment.

The line to the airport is basically an extension of the current line around across the western line to the airport. More than likely the SWRL will also be extended to the airport. There will be two options. The NWRL will not be the route to the airport from the city, although that option is available, common sense will see use of the Western line then changing to Airport (Oh wait Sydney siders don't know how to change trains)  or go via the SWRL route.

Basically every now and then you need to stop making something backward compatible in order to move forward.

Vote 1 Transtopic for Premier.

Perhaps related - I think there is an excessive focus at the moment on choosing a technology in terms of "passengers per hour". That's not actually the real driver for a public transport system. You don't just need people to get on and off your sets, you actually need to transport them some distance. When you start looking at capacity versus likely demand for that line in terms of passenger-kilometres per hour I think the decision to go single deck looks very dubious.

(I don't subscribe to the rants that they had to go single deck in order to provide a clean break with all the industrial relations or whatever evils the legacy system currently entails - that's just ideological babble. If that's what's motivating you then there are plenty, plenty, plenty of other options that force that break that don't entail infrastructure limitations that will be with you for the rest of time.)

If you are going to build additional near-inner-city lines (and we should, with additional city stations) absolutely build them to a smaller rolling stock profile (because you are going to be doing a lot of tunnelling...) and configure them so you can poke as many services per hour down them - all in classic "metro" style (and as you do that, the need to operate the DD lines as poor man's metros becomes less - so you can start to reconfigure them too). But if you are going to be building new lines out in the boondocks (and with clear potential for the line to be extended much further to upper western outer boondock heights - FFS they are ALREADY seriously talking about the corridor heading south to Badgerys, let alone whereever else) it doesn't make sense to me.

Alas... too late now.

Thanks for your support.  It's all common sense really.

The terminology being thrown around I think is if anything confusing the issue, especially by the pollies as they have to manage the selling of this.

For my mind the reasons behind the NWRL are
- Its fully automated, hence significantly reduced lifetime operation costs. Its the way every other commuter line is being built where the opportunity is available. Really do we need to go much further why the current Cityrail network expansion is been drawn to an end? Nothing to do with union, its just what is happening everywhere when the option is available.

Has nothing to do with tunnel bore.  False premise as well - the current network is continuing to expand.

- Its off the shelf technology and hence lower CAPEX?

The technology has nothing to do with tunnel bore, apart from setting a minimum.  Smaller tunnels are cheaper, but the difference in price in the context of this particular project is not large.

- Sydney has moved to sectoriation, so trains don't mix lines like they used to, the need for alternative corridors and paths is how the system operates now or the future. Trains operate A-B-A. Due to peak hour congestion, if one line is blocked, often not much can be done anyway and with time even less.

Has little to do with tunnel bore. Sectorisation is grand, but do you know what the ideal approach to sectorisation will be in 30 years time?

- Sydney DD's stock has two doors because many stations have excessive curvature. The NWRL and the existing ECRL have straight to mostly straight platforms, hence multiple >2 door option rolling stock is an option that should be taken. Despite what many think the dwell time issue is not limited to 3 city stations. Its been a number of years since I commuted in Sydney, but Chatswood and numerous other stations I used to travel by also have slower dwell times. Cutting 5-10sec off per station along a line saves a few minutes per cycle which can be converted to less rolling stock.

The number of doors has nothing to do with tunnel bore.

- The current manually driven DD's with the best technology on offer will not exceed 2min through the city and its unlikely less than 2.5min is indeed practical. Greenfield automated RT's with more doors are doing 90sec.

Has nothing to do with tunnel bore.

History has shown that getting rolling stock supplied to Sydney involves custom made equipment due to its relatively unique profile. DD is far from unusual as its very common in Central Europe, but its not the same as there. Each contract has had numerous issues and costs per seat are probably way above standard equipment.

The line to the airport is basically an extension of the current line around across the western line to the airport. More than likely the SWRL will also be extended to the airport. There will be two options. The NWRL will not be the route to the airport from the city, although that option is available, common sense will see use of the Western line then changing to Airport (Oh wait Sydney siders don't know how to change trains) or go via the SWRL route.

Basically every now and then you need to stop making something backward compatible in order to move forward.

By all means run fancy single deck many door automated trains on the NWRL if that floats your boat (but as I've said, I don't think it is single deck a good fit given the context).  But the asset you are building today has a lifetime of perhaps 100 years.  Given the additional cost associated with a "standard" bore tunnel is not that significant and given the line is very likely to get longer still and perhaps intersect again with the existing network in ways that are hard to predict today, it strikes me as silly to not keep the basic tunnel outline consistent.

You don't have to fit the tunnels out to allow DD operation today.  You can still have your single deck/off-the-shelf/lots-of-doors/fully-automated/privately operated installation.  Perhaps in future it might still cost a lot to change whatever tunnel and station fit-out you install today to allow DD operation - say hundreds of millions of dollars.  But hundreds of millions of dollars to unlock an option is potentially peanuts compared to the cost of having to bore new tunnel infrastructure!

The next stage of this project - crossing the harbour - which provides the next quantum of capacity into the Sydney CBD - comes at a substantial cost due to the geographical constraints.  That is - it is going to be expensive capacity.  That's unavoidable to an extent, but it means that when you decide to spend to add that capacity you should try and work it as hard as you can as soon as you can.  But I don't think the demand from the NWRL is even going to touch the sides of what you could poke down a new harbour crossing.

I accept that the NWRL Rapid Transit is now a fait accompli, literally set in concrete so to speak with the first TBM now in the ground, not that I agree with it. So my attitude is to make the most of what we have before us and my preference would be to extend the rapid transit across the harbour to areas not currently served by a rail service, such as the West Metro to Olympic Park, Parramatta and Westmead in the corridor north of Parramatta Rd, rather than trying to convert parts of the existing Sydney Trains network. The issue with me is not so much a preference of DD over SD, but an unrealistic attempt to convert a legacy suburban rail system into a modern automated rapid transit system, particularly where it compromises the overall efficiency of the broader rail network.

The existing Sydney Trains network may have its shortcomings and despite what you may think, it still provides a reasonably efficient service, but that doesn't mean it can't be improved upon. You can't make comparisons between an extensive legacy suburban rail system and a new greenfield rapid transit/metro system in cities which haven't had the benefit of a large suburban rail network previously. You don't throw the baby out with the bath water. The Sydney Trains network could operate more efficiently if the politicians had the intestinal fortitude to address its shortcomings. It's been done before in other jurisdictions (to quote Ron Christie).

The Sydney Trains network, thanks to the vision of Dr Bradfield, is already a hybrid suburban/metro system with trains continuing from the outer suburbs through the city centre. There is no immediate need for an incompatible rapid transit/metro system. The problem with the current system is not delays caused by dwell times at the major CBD stations, but the failure to provide additional track capacity through the CBD. You can't just "fix" a large rail network like Sydney's by completely ignoring it and building something else. The existing DD network, with additional upgraded track capacity through the CBD, could quite easily handle Sydney's rail traffic well into the future before any separate rapid transit system should even be considered. The priority should be to continue upgrading the existing network with ATP and ATO.

There is an overemphasis on dwell times for DD stock at the major CBD stations (Central, Town Hall and Wynyard) on the existing lines, but very little acknowledgement of how this would not be an issue on a new line through the CBD. There is no problem with dwell times for DD stock outside of the CBD, despite the government's rhetoric. Outer suburban areas, including those on the NWRL, do not warrant a train service every 2 or 3 minutes. Inner suburban stations with that level of service can adequately handle passenger flow because it is essentially one way, either getting on or getting off, depending on whether it's morning or evening peak. The maximum train capacity of 30 tph through a new CBD spine, with modern station design, could also handle passenger flow without excessive dwell times for DD stock. It would also take pressure off the existing CBD stations. But it's all academic now.

Just as an aside, contrary to your assertion that a large chunk of commuters from the North West don't travel to the city, the overwhelming majority of buses from the North West currently travel direct to the city with minimal services to Macquarie Park, let alone to Chatswood and North Sydney. A significant number do drive, because of the abundance of free parking, and that's unlikely to change even with the introduction of the NWRL.

Not arguing with the current efficiency of the Cityrail network, I'm arguing that is this best best approach for what is the start of a 2nd harbor crossing and expanded network. Currently there are large sections of track that cannot be used at full capacity due to congested bottle necks. I'm also arguing that moving to an automated system will reduce operating costs and lower operating subsidy means network expansion is more affordable.

Not sure how NWRL will be compromising the efficiency of the current network. There will be a progressive shift of some sections to a different technology which uses a different route through the city. Thus enabling the remaining sections to operate on a less congested city section and this enable more trains from the outer suburbs which is what the the DD's are best at doing. You yourself stated that 15-20km radius should be a limit. The Bankstown loop mostly complies with this.

My personal experience of commuting Sydney a few years back was Chatswood was one of numerous stations with extended dwell times. They may not be as long as Town Hall, but its still there. The new line will most likely have a more up to date design with more doors per length of trains and stations that are more efficient at moving people than Town Hall. Some German stations have a platform each side of the train with one side alighting and the other boarding with a delay on the boarding doors. I would hope the new line has this at key stations.

I looked up the govt survey of commuters from the NW to final destination which indicates about 1/3 to 1/2 of commuters travel along the route of the NWRL project, but not further. This data was used to support the design of the NWRL phase 1 to Chatswood only.

Yes, a whole new route could be built from Redfern to Chatswood with the NWRL built to DD standard and achieve a similar physical route outcome, but this completely ignores the opportunity to shift to a lower operating cost model transport medium.

I would strongly agree if the NWRL is looked at in isolation the path taken by the govt is questionable, but since both ALP and LNP seem to support a similar approach then you have to wonder how wrong it is. The ALP had plans to build the inner NW metro that was eventual forecast to reach Epping (and beyond?) problem with their plan was again the first stage was questionable. The former ALP govt had burnt meany a bridge even with the feds and hence they struggled to get support. I think had they proposed a line to be built in one go to Epping they would have got more support.

For me when looking at the NWRL project, you have to look 20-30 years ahead and see what doors this opens. Bradfield is often referenced as a man of vision for Sydney, I'm sure when he was building the tunnels and other projects he was questioned why. So why cannot we do the same?

The terminology being thrown around I think is if anything confusing the issue, especially by the pollies as they have to manage the selling of this.

For my mind the reasons behind the NWRL are
- Its fully automated, hence significantly reduced lifetime operation costs. Its the way every other commuter line is being built where the opportunity is available. Really do we need to go much further why the current Cityrail network expansion is been drawn to an end? Nothing to do with union, its just what is happening everywhere when the option is available.

- Its off the shelf technology and hence lower CAPEX?

- Sydney has moved to sectoriation, so trains don't mix lines like they used to, the need for alternative corridors and paths is how the system operates now or the future. Trains operate A-B-A. Due to peak hour congestion, if one line is blocked, often not much can be done anyway and with time even less.

- Sydney DD's stock has two doors because many stations have excessive curvature. The NWRL and the existing ECRL have straight to mostly straight platforms, hence multiple >2 door option rolling stock is an option that should be taken. Despite what many think the dwell time issue is not limited to 3 city stations. Its been a number of years since I commuted in Sydney, but Chatswood and numerous other stations I used to travel by also have slower dwell times. Cutting 5-10sec off per station along a line saves a few minutes per cycle which can be converted to less rolling stock.

- The current manually driven DD's with the best technology on offer will not exceed 2min through the city and its unlikely less than 2.5min is indeed practical. Greenfield automated RT's with more doors are doing 90sec.

History has shown that getting rolling stock supplied to Sydney involves custom made equipment due to its relatively unique profile. DD is far from unusual as its very common in Central Europe, but its not the same as there. Each contract has had numerous issues and costs per seat are probably way above standard equipment.

The line to the airport is basically an extension of the current line around across the western line to the airport. More than likely the SWRL will also be extended to the airport. There will be two options. The NWRL will not be the route to the airport from the city, although that option is available, common sense will see use of the Western line then changing to Airport (Oh wait Sydney siders don't know how to change trains) or go via the SWRL route.

Basically every now and then you need to stop making something backward compatible in order to move forward.

You're missing the whole point.  Sydney is not a high density city and at this stage of its development, it doesn't need a high capacity rapid transit/metro system such as those now being introduced in Asia.  It may well require such a system in the future within developing higher density inner city areas.  We don't need rapid transit stretching out into the low density fringes of the metropolitan area, such as the NWRL, and we certainly don't need a service every 90 seconds.  It's pure overkill.  

We have a large suburban rail system which already delivers passengers into and through the city centre and any extensions of the system into the outer suburbs should be integrated with the current network. The focus should be on improving that network before any thought is given to establishing a separate rapid transit system for the inner city and it shouldn't confiscate any part of it.

As far as equipment goes, the government could have quite easily extended the Waratah contract (I believe there was an option to do so) getting a ready made proven design without the cost of modifying any so called "off the shelf" trains from overseas.

The DD's do a good job, but they are best used for longer runs than shorter. The other issue is that the whole technology in Sydney is do damn expensive to operate for the people they move. Things need to change and the SWRL is basically the line in the sand, move to something more off the shelf and more compatible with other networks. Germany doesn't run DD's on inner suburban, metro services. Yes the NWRL is a long line by some standards as a Automated Metro, but Dubai runs a 50km long Red line 100% automated, others will follow.

Germany only has one city (more like two half cities in many respects) even half the size of Sydney, and nothing anywhere near as challenging geographically.  If Sydney were in Europe, it would be one of the top 5 cities population wise.  Yet there are hundreds of European cities with more rail infrastructure than Sydney.  The DD's were a solution to this relative lack of infrastructure, not the cause of it.

I don't disagree with the idea Sydney is too expensive.  There are many reasons for this, but the loading gauge being too big certainly isn't one of them.  However, the cumulative effects of changing the loading gauge every 30 or 40 years most definitely is.

Yes, a whole new route could be built from Redfern to Chatswood with the NWRL built to DD standard and achieve a similar physical route outcome, but this completely ignores the opportunity to shift to a lower operating cost model transport medium.

No it doesn't.

Where are the significant operating cost savings in running single deck versus double deck?

Now that the NWRL Rapid Transit is set in concrete with the announcement of the final contract for the project, here is my wish list for the future development of Sydney's rail network over the next 15 to 20 years.

- The future extension of the NWRL Rapid Transit across the harbor should connect with the previously proposed West Metro to Parramatta/Westmead (or even
  Blacktown) via Barangaroo, rather than confiscating the existing Bankstown Line.

- Future extensions to the Rapid Transit network could be a Northern Beaches Line in the North and a Southern Line to Miranda and Cronulla via Newtown and
  Sylvania, or possibly a line from Five Dock following the alignment of Great North Road across the Parramatta River (only one harbour crossing) to Gladesville,
  Top Ryde, Eastwood and Epping, interchanging with the NWRL.

- Completion of quadruplication of the Northern Line between Rhodes and West Ryde as the next stage of the Northern Sydney Freight Corridor Program,
  providing full quad from Strathfield to Epping, with greater flexibility for Suburban, Intercity and freight services.

- Reinstatement of the Western Express proposal from Eveleigh to Barangaroo (piggybacking the West Metro) to increase capacity on the Western and Northern
  Lines.

- Realigning the flyover junction from Seven Hills to Blacktown to connect the Richmond Line directly with the Western Main Line tracks instead of the current
  Suburban Relief tracks so that all Richmond Line services travelled to Barangaroo, without any conflicting crossover being required.

- Upgrading the signalling on the Western Main between Strathfield and Barangaroo to permit at least 24 tph (preferably 26 tph).  The Western Main would then
  be used exclusively by Intercity from Newcastle/Central Coast and Blue Mountains (to Sydney Terminal) and Western and Northern Line Express services to
  Barangaroo.

- Completion of quadruplication from St Marys to Penrith on the Western Line.

- Extension of duplication on the Richmond line to at least Vineyard.

- Restoration of services to Liverpool (extending to Glenfield or Campbelltown ) via Regents Park.

- All services to Liverpool and beyond via both Regents Park and Granville be transferred to the Suburban tracks between Central and Homebush following
  transfer of some Western and Northern Line services to the Main Line tracks.  This would allow for a consistent all stations stopping pattern with increased
  frequency on the Inner West Local from Homebush to Central (say 12 tph or better).

- Cessation of services to Liverpool via Bankstown and instead redirect all Bankstown line services to Lidcombe.  Also possible construction of passing loops to
  allow limited stop express services to overtake all stations services.

- Reinstatement of completion of sextuplication between Sydenham and Erskineville to separate the Bankstown Line from the Illawarra Main and Local tracks
  and connecting directly with City Circle Inner (and City Circle Outer via the flying junctions at Central).

- llawarra Local tracks from Erskineville be realigned to connect with the Illawarra Dive to Sydney Terminal and the unused Redfern platforms 9 & 10 and
  underground Central platforms 26 & 27.

- Future extension of above along the MetroPitt corridor to a terminal station at Circular Quay.

- The Illawarra Main to become an all stations service from Hurstville to Bondi Junction (renamed the Illawarra Local).  All express Intercity, Cronulla and
  Waterfall services to run via the Illawarra Local (renamed Illawarra Main) from Hurstville as far as Wolli Creek, switching to the renamed Local (except for
  Intercity), continuing to Bondi Junction.

- Construction of grade separated junction between Illawarra Main and Illawarra Local at Wolli Creek.

- Extension of Eastern Suburbs Line to Maroubra Junction, as recommended by Infrastructure NSW, to increase its catchment area.  An extension of the Light
  Rail along the old tram reservation from Kingsford to Maroubra Junction and possibly to Malabar/La Perouse would also be worthy of consideration.  

- Extension of quadruplication of the East Hills Line from Revesby to Glenfield in anticipation of the establishment of Badgerys Creek Airport and the extension
  of the South West Rail Link to service it.  This would allow for express services from Badgerys Creek to both Sydney Airport and the city via Sydenham.

Other longer term proposals that I would recommend would be to complete electrification of the South Coast Line to Nowra as well extending it to Moss Vale and possibly Maitland to allow for direct services to Sydney, without the need for an alternative diesel rail car service.

I may have missed some things, but I would welcome any feedback on what I have proposed or any alternative suggestions.

All of the previous comments I am sure are relevant.
My opinion is we should have bored the tunnels to enable DD stock to run then run your single deck train to your hearts content.
Then in seventy five years from now with different thinking you could run your DD stock if desired.
If they will not fit within now they never will so you have effectively engineered your options to be less than what could have been a possibility for a mere 8.3 billion dollars. Not bad value in these lean times?
PTE

No it doesn't.

Where are the significant operating cost savings in running single deck versus double deck?

I did say its not about DD vs SD, its about the current Cityrail manually operated custom made stock versus off the shelf automatic stock. The driver and guard add hundreds $ per hour to the operating cost of each train. This includes the need to supply and maintain a two drivers cabs per 8 car set.

You're missing the whole point. Sydney is not a high density city and at this stage of its development, it doesn't need a high capacity rapid transit/metro system such as those now being introduced in Asia. It may well require such a system in the future within developing higher density inner city areas. We don't need rapid transit stretching out into the low density fringes of the metropolitan area, such as the NWRL, and we certainly don't need a service every 90 seconds. It's pure overkill.

We have a large suburban rail system which already delivers passengers into and through the city centre and any extensions of the system into the outer suburbs should be integrated with the current network. The focus should be on improving that network before any thought is given to establishing a separate rapid transit system for the inner city and it shouldn't confiscate any part of it.

As far as equipment goes, the government could have quite easily extended the Waratah contract (I believe there was an option to do so) getting a ready made proven design without the cost of modifying any so called "off the shelf" trains from overseas.

The inner suburb belt of Sydney will have some of the highest population growth rates as more higher density builds are dropped in replacing lower density housing. Most European cities are capped at 5-7 stories in the Inner city, Sydney is far less limited. Its also not about what is happening now, back to the references to Bradfield its about 20-50 years time.

90sec needs to be factored in for the future, its not inconceivable this will ultimately be required in the city but yes may never be required further out. But this applies to every rail technology. Over capacity in city, under capacity outer suburban.

The Waratah could be extended and probably will be, but this platform cannot last forever as we have seen in past the next generation will have its own issues. At least these issues are now capped to the existing network.

Other cities don't feel so compelled by their current networks not to use newer technology when its available when a new line is being built. Singapore, Paris, Some German cities, Vancouver and that's just my experience.

The NWRL from Epping on its own is unlikely to justify the change, but its part of a much bigger picture. The NWRL is a branch of what will eventually be a large network. Maybe in 50 years time extending to Manly and other parts of the city on south side outside the current nominated routes and inner west main.

All of the previous comments I am sure are relevant.
My opinion is we should have bored the tunnels to enable DD stock to run then run your single deck train to your hearts content.
Then in seventy five years from now with different thinking you could run your DD stock if desired.
If they will not fit within now they never will so you have effectively engineered your options to be less than what could have been a possibility for a mere 8.3 billion dollars. Not bad value in these lean times?
PTE

Problem is its not just about the tunnels diameter. No one builds large scale infrastructure on the basis that in 30-50years time we may change our mind? At $8.3B they have probably already gone through to try and remove ever $1 possible including choice of technology. To build the tunnel that extra width, even if its just $10m could be argued that its a blatant waste of taxpayers money when they have no need for it.

The rollingstock ordered with the project will like Cityrail stock have a working life of 30-40 years. Future expansions will add to this stock at a later date thus further extending the time frame when conversion maybe desired. To do so before means you would have a large fleet of trains unusable.

Germany only has one city (more like two half cities in many respects) even half the size of Sydney, and nothing anywhere near as challenging geographically. If Sydney were in Europe, it would be one of the top 5 cities population wise. Yet there are hundreds of European cities with more rail infrastructure than Sydney. The DD's were a solution to this relative lack of infrastructure, not the cause of it.

I don't disagree with the idea Sydney is too expensive. There are many reasons for this, but the loading gauge being too big certainly isn't one of them. However, the cumulative effects of changing the loading gauge every 30 or 40 years most definitely is.

The high cost isn't due to just loading gauge, if at all. Not sure how it compares to the Central European popular DD's?

The whole platform is custom made for Sydney and Sydney only. No other city uses the same equipment. Yes electronics, traction motors, maybe even seats, but its all put in one package for one customer who every 10years or so goes out for tender for what is a moderate sized order.

The DD was introduced as a way to increase capacity using what they had available at the time for a low density city. Times have changed. DD's have their place, but they are not everything to everyone which is why so few if any green field networks use them. Automated trains with large door space as % of train length with stations built for them move more people faster.

Now that the NWRL Rapid Transit is set in concrete with the announcement of the final contract for the project, here is my wish list for the future development of Sydney's rail network over the next 15 to 20 years.

- The future extension of the NWRL Rapid Transit across the harbor should connect with the previously proposed West Metro to Parramatta/Westmead (or even
Blacktown) via Barangaroo, rather than confiscating the existing Bankstown Line.

- Future extensions to the Rapid Transit network could be a Northern Beaches Line in the North and a Southern Line to Miranda and Cronulla via Newtown and
Sylvania, or possibly a line from Five Dock following the alignment of Great North Road across the Parramatta River (only one harbour crossing) to Gladesville,
Top Ryde, Eastwood and Epping, interchanging with the NWRL.

- Completion of quadruplication of the Northern Line between Rhodes and West Ryde as the next stage of the Northern Sydney Freight Corridor Program,
providing full quad from Strathfield to Epping, with greater flexibility for Suburban, Intercity and freight services.

- Reinstatement of the Western Express proposal from Eveleigh to Barangaroo (piggybacking the West Metro) to increase capacity on the Western and Northern
Lines.

- Realigning the flyover junction from Seven Hills to Blacktown to connect the Richmond Line directly with the Western Main Line tracks instead of the current
Suburban Relief tracks so that all Richmond Line services travelled to Barangaroo, without any conflicting crossover being required.

- Upgrading the signalling on the Western Main between Strathfield and Barangaroo to permit at least 24 tph (preferably 26 tph). The Western Main would then
be used exclusively by Intercity from Newcastle/Central Coast and Blue Mountains (to Sydney Terminal) and Western and Northern Line Express services to
Barangaroo.

- Completion of quadruplication from St Marys to Penrith on the Western Line.

- Extension of duplication on the Richmond line to at least Vineyard.

- Restoration of services to Liverpool (extending to Glenfield or Campbelltown ) via Regents Park.

- All services to Liverpool and beyond via both Regents Park and Granville be transferred to the Suburban tracks between Central and Homebush following
transfer of some Western and Northern Line services to the Main Line tracks. This would allow for a consistent all stations stopping pattern with increased
frequency on the Inner West Local from Homebush to Central (say 12 tph or better).

- Cessation of services to Liverpool via Bankstown and instead redirect all Bankstown line services to Lidcombe. Also possible construction of passing loops to
allow limited stop express services to overtake all stations services.

- Reinstatement of completion of sextuplication between Sydenham and Erskineville to separate the Bankstown Line from the Illawarra Main and Local tracks
and connecting directly with City Circle Inner (and City Circle Outer via the flying junctions at Central).

- llawarra Local tracks from Erskineville be realigned to connect with the Illawarra Dive to Sydney Terminal and the unused Redfern platforms 9 & 10 and
underground Central platforms 26 & 27.

- Future extension of above along the MetroPitt corridor to a terminal station at Circular Quay.

- The Illawarra Main to become an all stations service from Hurstville to Bondi Junction (renamed the Illawarra Local). All express Intercity, Cronulla and
Waterfall services to run via the Illawarra Local (renamed Illawarra Main) from Hurstville as far as Wolli Creek, switching to the renamed Local (except for
Intercity), continuing to Bondi Junction.

- Construction of grade separated junction between Illawarra Main and Illawarra Local at Wolli Creek.

- Extension of Eastern Suburbs Line to Maroubra Junction, as recommended by Infrastructure NSW, to increase its catchment area. An extension of the Light
Rail along the old tram reservation from Kingsford to Maroubra Junction and possibly to Malabar/La Perouse would also be worthy of consideration.

- Extension of quadruplication of the East Hills Line from Revesby to Glenfield in anticipation of the establishment of Badgerys Creek Airport and the extension
of the South West Rail Link to service it. This would allow for express services from Badgerys Creek to both Sydney Airport and the city via Sydenham.

Other longer term proposals that I would recommend would be to complete electrification of the South Coast Line to Nowra as well extending it to Moss Vale and possibly Maitland to allow for direct services to Sydney, without the need for an alternative diesel rail car service.

I may have missed some things, but I would welcome any feedback on what I have proposed or any alternative suggestions.

Most of what you stated I mostly agree with although I don't think some of the suggestions will delivery efficient capacity. I'd also look to expand at same time reduce the operating costs. Interurban's need to be progressively removed from suburban traffic to improve capacity for both. Likewise inner suburban.

- NWRL Metro to City
- Manly/lower Nth beaches Metro to connect to above at Nth Sydney
- Metro from St Lenards would sweep east of current NSL/Pac hwy to Nth Sydney to improve catchment
- Removal of Waverton and Wollstencraft and combine to one station and realign the NSL via tunnel.
- Inner NWRL from City to Epping via Victoria Road
- Quad Strathfield to Hornsby
- Connection of NWRL and Richmond line

- Inner West local to Homebush to converted to Metro and extended on new pair of tracks to Olympic Park and Lidcombe
- Bankstown line to be converted to Metro and enable return of Loop via inner west
- Bankstown Metro to be connected to Nth side Metro in city
- Suburban western and south west suburban via Lidcombe now stop Lidcombe, Homebush, Straithfield, Burwood, Redfern only
- Inter urban west on nth tracks to Straithfield and merge with Nth interurban to Central
- Extension of Inner North West Metro from Epping to Paramatta using part of Carlingford line and on to Parammatta and new airport
- Further duplicate to Richmond
- Quad to Penrith
- Upgrade interurban line from Blacktown to Redfern to enable 140km/hr running as much as possible
- Western express suburban service to Blacktown to utilise interurban line on similar stopping pattern.

- Bondi extend to Bondi Beach, consider as loop line from BJ so no turn back required. Paris Line 6(?) does this.
- Eastern Light rail, Y junction at hospital/uni, one heads south the other up to Bondi Junction OR to HR to Uni but I suspect LR is more practical)

- SW line extension to new airport with express connection to Mascot and city.

- Hurtsville convert to Metro
- Cronulla/Waterfall run limited express from Hurtsville to Wollicreek
- Complete 6 tracks past Sydenham (2 for interurban/express, 2 for metro, 2 for suburban)

- Fully Quad East Hills and separate route for interurban services

Interurban
- Realignment/curve easing from Asquith to Gosford to cut at least 15min (saves 30min on return service, cuts a set/crew from service)
- Realignment/curve/duplication easing Sutherland to Wollongong to cut at least 15-20min
- Realignment/curve easing Emu Plains to Katoomba or Mt Vic to cut 15-20min
- Curve ease the single track section to Bathurst
- Maldon to Dombarton line
- Realignment of south line to Moss Vale

Problem is its not just about the tunnels diameter. No one builds large scale infrastructure on the basis that in 30-50years time we may change our mind? At $8.3B they have probably already gone through to try and remove ever $1 possible including choice of technology. To build the tunnel that extra width, even if its just $10m could be argued that its a blatant waste of taxpayers money when they have no need for it.

It was rumoured that a contractor had offered to build the tunnels to the larger diameter at no additional cost, but they were told to go away.  Whichever slant you want to put on it, the decision to construct smaller tunnels was clearly nothing but an act of sheer bastardry to ensure that DD trains could never run on it and be reintegrated with the Sydney Trains network in the future. However, that wouldn't preclude a future government integrating the NWRL with the current network by running compatible SD trains (which was the original intent with the Sydney Rail Futures program).  ATO isn't exclusive to metros.

Rumours are not always true and in the case of making a TBM to a wider profile I have even less faith in rumours.

In 10 yrs time when the city and sourthen side is open I suspect the public opinion will towards more and not less.

As mentioned many times its not DD vs SD its current Sydney trains cost model versus what is available on market now off the shelf.