Auckland's City Rail Link - a very expensive punt, or the city's key economic enabler? Gareth Vaughan wades through the Business Case

Auckland's City Rail Link - a very expensive punt, or the city's key economic enabler? Gareth Vaughan wades through the Business Case

By Gareth Vaughan

The phrase 'bigger than Ben Hur' was coined after the 1959 release of the then very expensive $15 million Hollywood movie Ben Hur. Basically it's a saying used to refer to something of extravagant and epic proportions.

It's easy to paint Auckland's up to $3.4 billion City Rail Link as the city's transport Ben Hur. Or it that price it could be argued it's bigger than Ben Hur, which in its day was the second highest grossing film in history, winning 11 Academy Awards.

So will Auckland's City Rail Link prove as successful?

I've had a wade through the City Rail Link Business Caseissued by Auckland Transport, an Auckland Council controlled organisation, to try and find the answer.

The Business Case certainly talks the project up. The City Rail Link, expected to be completed by 2023/24, is described as an economic enabler and an urban redevelopment catalyst that will provide a station within 10 minutes walk of anywhere in the City Centre.

The Business Case paints a picture of a project that's a lot more than just a rail tunnel. 

It's described as "a lead investment whose major purpose is as an economic intervention, providing transport capacity to enable the top wealth creating location in New Zealand to grow." And, "The City Rail Link is essentially an economic enabler providing the accessibility needed for Auckland's primary economic engine - the City Centre - to grow."

The $3.4 bln price tag is equivalent to the Govt's annual law & order budget

The project's cheer leaders, led by outgoing Mayor Len Brown, eventually won an initially sceptical National Party-led government over. This culminated in a watershed moment last month when the Government announced it (read taxpayers) will stump up 50% of the cost of the City Rail Link. Auckland Council (Auckland ratepayers) will pay the other half. The total cost of the project is currently estimated at between $2.8 billion and $3.4 billion.

To put that price tag in context the Government's 2016 Budget allocated less money to each of tertiary, secondary and primary education, which received $2.1 billion, $2.1 billion and $3 billion, respectively. The $3.4 billion upper end of the City Rail Link's estimated cost matches the 2016 law and order budget. Auckland Council's half contribution towards the project is roughly equivalent to its June year rates revenue of $1.564 billion.

By way of comparison, two of the other major transport infrastructure projects underway in New Zealand, Auckland's 2.4 kilometre Waterview Connection which is half underground, and Wellington's 27 kilometre Transmission Gully motorway, are expected to cost $1.4 billion and $850 million, respectively.

Why is it needed?

So what exactly is the City Rail Link and why is it needed?

It's a 3.45 kilometre rail link, largely via tunnel, from the downtown Britomart Station up to a redeveloped Mt Eden Station. It will include two new underground stations - Aotea and Karangahape Road. According to the Business Case, the City Rail Link will allow 20,000 more passengers per hour to conveniently access the City Centre than would otherwise be possible.

The Business Case acknowledges additional investment in Auckland's rail system will be needed beyond the City Rail Link to provide a "truly world class" railway. But it points out the project will remove a dead-end terminus at Britomart, where trains have to enter and reverse out on the only two tracks available, and remove the need for western line trains to reverse at Newmarket, the second busiest station.

There are also plans for bus routes to be reworked to act as feeder services to suburban stations, thus reducing the numbers of buses arriving in the City Centre from directions where the rail line runs such as the west, and allowing more bus services from other regions, such as the north, that aren't served by rail. In this way, the Business Case argues, the City Rail Link will provide "indirect benefits" to a wider area of Auckland than merely immediate rail catchments.

Here's some of the key argument as to why the City Rail Link is needed, taken from the Business Case.

The fundamental constraint that applies to the Auckland rail network is the maximum train frequency at the Britomart Transport Centre. With only two lines feeding the five platforms in this terminal station the maximum planning capacity is 20 trains per hour. With six trains on each of the main lines in the peak – southern, eastern and western – and two trains per hour on the Onehunga line, the peak period capacity is fully taken up without the CRL [City Rail Link]. 

Further constraints on the rail network at critical junctions and between Wiri and Westfield are planned to be addressed in parallel with CRL construction. These are identified within the Regional Land Transport Plan (RLTP) although funding remains uncertain.

Rail patronage has been growing rapidly in recent years. If the trend were to continue the rail network could be carrying 20m passengers per annum – which the Government has identified as one trigger for investing in the CRL – as soon as 2017.

Once the principal constraint has been addressed, with the CRL turning Britomart into a through station, it will be possible to run up to 24 services per hour, each way, through the Link, with initial plans for 18 services per hour in the peaks. Ultimately, advanced systems and further investment might see that figure rise to 30 services per hour. This means that the expected rapid increase in patronage as the railway progressively takes a greater share of demand with other modes being highly constrained, can be responded to with additional train services

Another argument put up in the Business Case as to why the City Rail Link is needed is to help Auckland's already creaking transport network cope with expected "rapid" population growth, from 1.5 million people to between 2.2 million and 2.5 million in 30 years. The City Rail Link will be a "section of the metro rail system" where high capacity electric trains can move large volumes of passengers.

Pushing the property buttons

For a property obsessed city, the Business Case pushes two key buttons. Firstly, it suggests the City Rail Link will provide enhanced access to the council-government Special Housing Areas, which include 14,000 potential sites near the rail network, and make affordable housing in outer areas more viable by improving public transport links. And secondly it promises increases in property values, estimating property values within 500 metres of each new station could increase by $1 billion, pointing to this British report by Steer Davies Gleave as evidence. 

"The results of our research suggest that the redevelopment of major city centre stations can support increases in property values of 30% or more. Moreover, the impact will tend to be greater where there is a legacy of underinvestment in the station and its environs, with knock-on effects on the surrounding area," the Steer Davies Gleave report says.

The report does, however, go on to say, "These findings should be treated with caution, as observed changes in property values will reflect the impact of a regeneration scheme as whole rather than the station investment in isolation. Station investment must therefore be seen as an important, although not the only, element in a wider process of economic regeneration."

The diagram below outlines benefits the Business Case argues the City Rail Link will deliver.

So what's all the money for?

So just how and why is the project going to cost so much?

Asked for a breakdown of what the $2.8 billion to $3.4 billion cost estimate is made up of, an Auckland Transport spokeswoman simply said the estimate covers "everything associated with the project", including investigation, design, property purchases, planning and construction.

The chart below comes from the Business Case, which was published last year. The total cost estimate has since increased.

Running at a loss

The operating and maintenance costs for the new tunnel and stations are put at $50 million a year. The Business Case estimates $20 million of this will be generated from fare revenue, with Auckland Council and the New Zealand Transport Agency jointly picking up the tab for the balance.

The Business Case puts the City Rail Link's benefit-cost ratio at 1.6 to 1.7, including wider economic benefits. That means it's expected to deliver $1.6 to $1.7 of benefits for every $1 invested.

In comparison, the Waterview Connection is expected to deliver $1.16 of benefits for every $1 invested, and Transmission Gully's expected to deliver $1.6 of benefits for every $1 invested. The benefit-cost ratio for Auckland's $1.25 billion to $1.85 billion East West Link, or East West Connections, is put at 1.4 to 1.9.

However, Government papers obtained by Radio New Zealand under the Official Information Act show Treasury and the Ministry of Transport didn't see the City Rail Link delivering such a strong return, and highlighted concerns it would do little to alleviate Auckland's traffic congestion.

"While the Council attaches considerable importance to the CRL as a city-shaping project, its economic case is not strong. Based on joint work conducted between government and Auckland Council in 2011 and 2012, Treasury and the Ministry of Transport consider that the likely benefit to cost ratio for the project would be somewhere between 0.4 and 0.9. This work also showed that the project has a modest impact on Auckland's congestion problems," Treasury and the Ministry of Transport said.

What about the GDP impact? Council & government to benefit

The Business Plan argues the new central city station at Aotea (near Aotea Square) will boost economic activity in that area, and new and redeveloped stations at Karangahape Road and Mt Eden will support economic and land-use changes planned there.

"Significant development is expected in all the station precincts, valued in total at some $1.2 billion to $1.4 billion, adding patronage as well as possible income for the Council where the development occurs on its land holdings, a form of direct value capture," the Business Case says.

Based on work by Australian firm SGS Economics and Planning, the City Rail Link is expected to lift economic output in 2026 by $48.8 million, equivalent to a 0.04% uplift to Auckland’s Gross Domestic Product (GDP), and in 2046 by about $173.1 million, equivalent to a 0.08% uplift to Auckland’s GDP. 

Interestingly, the Business Case suggests central government will be the big winner.

“Industries which cluster in the CBD will be ‘winners’ from the City Rail Link, but the largest single beneficiary is Central Government. Over the 40 year period, Central Government would collect around $1.4 billion (in undiscounted terms) in taxation revenue as a result of the City Rail Link.” 

What about the impact on traffic congestion?

The Business Case suggests, without the City Rail Link, congestion in Auckland will significantly worsen as road capacity increase slows and population growth outpaces infrastructure investment. It estimates the demand for travel over the next 30 years will increase by 50% "for person trips", with the volume of freight and commercial trips more than doubling.

While the City Rail Link should take cars off the roads in the central city, what impact will it have elsewhere? Will it noticeably reduce traffic congestion, or the growth of traffic congestion, across Auckland? Or will it just push congestion out a bit from the Central Business District? Time will tell.

The Business Case doesn't look at the potential impact on Auckland transport from the development of electric or, probably more importantly, driverless vehicles. 

Like Britomart Station before it, the City Rail Link feels like another piece of the broader Auckland public transport jigsaw. As noted in the Business Case, further investment will be needed to create a truly world class railway. The City Rail Link won't deliver train stations to suburbs in Auckland currently lacking them. And what does it mean for, and how would it work next to, potential future major transport projects such as reintroducing light rail or trams, and another Waitemata Harbour crossing?

 In terms of big future projects there are, of course, questions about how they could be funded.

The council's Auckland Plan points out that over 30 years new funding mechanisms will be required to help finance the up to $15 billion funding shortfall for transport projects. A range of funding mechanisms could be used including; general rates, targeted rates, development contributions, tax increment financing, regional fuel tax and road user charge/diesel levy, tolling new roads, road pricing on existing roads being some form of network charging or congestion charging, additional car parking charges, visitor taxes, and airport departure tax.

Of course there's also borrowing, and there's the option of bringing in outside investors such as the New Zealand Superannuation Fund, the Accident Compensation Corporation or overseas investors.

What will Len's legacy be?

At the final meeting of the Auckland Council Governing Body for the 2013-2016 electoral term Deputy Mayor Penny Hulse said to Brown, "Your utter belief in the City Rail Link will be your legacy and should be yours alone."

When discussing Auckland's transport challenges many older Aucklanders like to point out things would be very different if the rail network championed by Dove-Myer Robinson, Mayor in the 1960s and 1970s, had got off the ground.

Unlike Robbie's dream, Len's is actually going to come true. Time will tell whether it creates a legacy to be proud of.

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CRL seems like grandiose king maker BS to me. Light rail to the airport, funding key enablers for the unitary plan incl improving community hubs, a harbour crossing for commuters and expanding the public transport network are all needed. We're leaving Auckland anyway, but feel sorry for anyone who thinks the tiny, cold, characterless downtown of Auckland CBD is a destination worthy of Len's $4b train set.

To work really well, there will need to be further investment beyond the inner city, but nevertheless the City Rail Link will surely be well used- as rail in Auckland is now. And it is an essential precursor to extra investment. I do note that in its wisdom Treasury is paying $3.125 billion for Transmission Gully, and not the advertised $850 million.
If they pay only $1.5 billion towards the City Rail Link then they have a real bargain. At their 2% cost of funds, that is $30 million per annum.

There seems like there is a lot of controversy regarding the cost of Transmission Gully -The Greens in 2012 were claiming $3 Billion with some documentary evidence.

NZCID try to clarify this $3 billion amount -basically it includes 30 years of private sector (it is a PPP scheme) maintenance work and interest charges.

I have heard that these ongoing charges that future governments will pay for Transmission Gully significantly constrain funding options i.e. it will consume a significant proportion of NZTA funding for decades. This limits future projects which the next government may have wanted to do.

Hah! That's a big IF!
More likely the cool 1 billion per kilometer triples as Transmission Gully did! That's a juicy pie with lots of fingers in it that will lead us further down the path of corruption. Tis' a changing world and one has to adapt, I guess...

it should have built way back when .
as usual we put off until its almost too late so the cost sky rockets.
same with the connection from onehunga to Avondale ant the connection from onehunga to the airport to manukau. both of which will never get built in my lifetime.
as for transmission gully classic USA offered to design and build all we needed to provide was materials, government of the day said nope not needed and now will cost a small fortune

The Auckland transport problems remind me so much of the horse racing industry in NZ.
Every body has a view on what needs to be done,but if its not their view then they are not interested.
In other words the horse industry and Aucklands transport problems are going nowhere fast.

If it costs $3.4 billion and it only gives $48 million increase in output, that suggests that the profit generated per annum will be about 2.4 million (at 5% net profit on turnover, if that is what the mysterious "output" refers to). The many 000s are confusing but I make that a return on investment of 0.07% per annum. Am I missing something?

Based on work by Australian firm SGS Economics and Planning, the City Rail Link is expected to lift economic output in 2026 by $48.8 million

Are you missing something?

Indeed you are.

If the rail link is not built and migration keeps on at current rates, and existing transport infrastructure remains fixed, the "efficiency" of AKL economic output will decline. It will not increase.

It will pointed out (by those in the know) that population growth increases GDP

If AKL population grows by 2% but AKL GDP only grows by 0.07% then those in the know will have to explain where the efficiency dividend went.

The CRL is not "expected" to be completed until 2024. Preliminary construction has already begun to impact traffic flows around the CBD. If CBD traffic grinds to a halt between 2017 and 2024, then simply completing the project should produce a $48 million dividend in congestion relief alone

You need to know what assumptions the SGS study made as to population growth, or nil growth

Yes, we are back to immigration. We are told it is good for us, that New Zealand has too few people, surely that is just cultural cringe. I'm quite happy about it on an individual level, it adds a bit of variety, but at scale it can be highly destructive. We are told that it increases GDP, but there is little evidence that it increases GDP per capita for existing residents. Increasing population does cause a shortage of houses, schools, railways, and roads. Those who are sitting pretty owning a house feel they benefit, while those who are more vulnerable definitely suffer.

If the population of Auckland has gone up by 200,000 over the last few years and we now need to spend $3.4 billion, doesn't that mean each new body requires an extra $170,000 of capital investment in rail alone?

I think thats a big IF. Migration ebbs and flows, it wont be too long before Australia fires again and we dip, the flow across the Tasman happens, we stagnate or go backwards. Its a sure thing.

“The best time to plant a tree was 20 years ago. The second best time is now.” – Chinese Proverb

Great investment should have been done years ago. As the population grows sooner or later you will need some way of getting more people on trains. Number 8 wire mentality onlys gets you so far. Some times you need to open your wallet.

Phil Goff congratulations !!!!

my first job was with the MWD so I learnt first hand about stupid government policy to build cheap that only is built for 20 years growth, which by the time it was approved built and completed took ten years plus so was a waste of time and over the long run a waste of money
we are still at it tacking on one extra lane here and there which with todays immigration is full as soon as finished
the other crazy thing is not building things together to save on overall cost, it may cost more at the time BUT it is cheaper than building separately at different times,
case and point rail to the airport not being built when they have and are remodeling the motorway from mangere bridge to the airport.

Talk about nebulous benefits. They are really scraping the bottom of the barrel for benefits aren't they. This is absolutely completely madness.
Did anyone look at putting more carriages on the trains to the existing stations? Lengthen the platforms? I've never seen that mentioned anywhere!
$3.85b is now the estimate of what it may blow out to. And at how many billions does the public wake up to the fact that this is just beyond ridiculous.
Unfortunately it has now got momentum, and the rates bills for all Aucklanders will be commensurately higher forever more, particularly when interest rates rise.

The road business cases aren't any better. Normally most of the benefits are from people saving a few seconds off peak, like the economy is going to drastically improve because of that.
My understanding is that they are limited by what they are allowed to include in business cases and they are all set up for roads.
Chucking more and more money at roads with the expectation that one day one of them might cure congestion is just plain madness

Vancouver tax to pay for it !!!!!

More cariages will not improve the travel times into the city this will. To get moree people on rail the service needs to improve dramtically. You cant have aspirations to have a world class city and have a 3rd world rail network.


Papakura Aotea Station 66 57 9 14%
Manurewa Aotea Station 56 47 9 16%
Papatoetoe Karangahape Station 52 34 18 35%
Swanson Karangahape Station 71 40 31 44%
Henderson Aotea Station 52 35 17 33%
New Lynn Britomart Station 33 26 7 21%
Kingsland Karangahape Station 37 6 31 84%
Manukau Karangahape Station 55 43 12 22%
Panmure Karangahape Station 35 23 12 34%
Glen Innes Aotea Station 27 18 9 33%
Onehunga Aotea Station 40 31 9 23%
Ellerslie Karangahape Station 35 17 18 51%
Newmarket Aotea Station 20 11 9 45%
Karangahape Station Britomart 18 6 12 67%

no amount of extra careiages will speed up the existing trains.
The fact you can have trains on the shore in the future is a huge win also

Need to get people on public transport ...madness stuck in car traffic every day

Best time now with interest rates low.. rememebr low interest rates should be just for residental property investment

You don't need a CRL to have trains to the Shore! Sure, it helps. But how many billions do you throw at this thing? Plus ongoing subsidies from rates. Most cost estimates at this stage do not include the work to get rid of level crossings where people tend to get squashed. The above small improvement in times would no doubt assume that no more bus lanes were put in. Len did not "do" bus lanes.

Great article !!!!!! Keep up the excellent work Gareth

Yes but hasn't the CRL been done to death already? What about someone actually critiquing a road business case for once? How can we possibly get more than $6 billion in benefit from a second road harbour crossing for example?

The article appears to mix two reports for the east -west link. The bcr of 1.4-1.9 was for a cost of $1-1.4b. The $1.2-1.8b would have a lower BCR
See Par 23

Neville, NZTA told me the 1.4-1.9 BCR was the latest one.

Yey! Increasing property values!
Just what we need.
I assume that the huge negative from the increased rates bills (and the increase in govt debt), from the construction cost and subsidy costs has been accounted for in the cost benefit study. if not, it should be re-done. Quickly.

Worth the paper it's written on. Anyone who has ever written a business case knows they are written backwards. You start with the answer you have to come up with then work backwards to the assumptions. The biggest assumption in this case is "if passenger growth continues at the same rate...". This is a huge assumption. Instinctively most people know that there is not an ever-expanding demand for transit to Auckland's CBD. So this business case would have had more credibility if the authors had commissioned independent research to establish the level of actual latent demand for train travel. The methods for researching that demand are well established and would have been cheap in the context of the overall project. But, apparently, the authors didn't think it important enough to do that basic research.

On another note the operating costs of the project are worth taking a look at. These are not the costs of running the rail network through the tunnel, it is the cost of simply owning the link and maintaining it. Of the projected $50m some $35m will be depreciation (assuming straight line depreciation of $3.5b over 100 years). Funding that depreciation assumes that this rail link will be needed forever, that driverless cars and car pooling (i.e. Uber Pool etc) will have no impact on land transport configuration, ever. That is because the accumulated depreciation forms a capital reserve to pay for the replacement of the tunnels and stations when they collapse in exactly 100 years time. If it turns out those assets don't have to be replaced then it becomes a slush fund.

Len's legacy will not only be a $3.5b white elephant but six years of waste avoiding working on real solutions to Auckland's problems.

Donald you are quite correct that by changing a few variables in the assumptions a business case can be made for or against any project. For instance NZ traditionally since WW2 has used a high interest rate when assessing the cost benefit ratio -this benefits projects with lower near term capital costs but higher future maintenance/ environmental costs like motorways. Wrt the CRL there has been much more public scrutiny than other transport projects -the vast majority of new transport spending is on mega motorway projects for RoNS -mostly in the North Island -and with very little public scrutiny.

Rail use in Auckland has been exceeding budgeted passenger projections unlike motorway projects. For motorway projects in Auckland the low hanging fruit has also been done and new projects are ramping up in price and decreasing in cost benefit returns.

Critics of the CRL make a big deal about it supporting the CBD but actually because it creates a loop not a dead end it benefits the entire network.

If people are worried about the effects the improvement on amenity values the CRL will create for property prices there are mechanisms to get this capitalised in increased density not increased price. There is a discussion at transportblog about this.

Scrutiny does not mean good business it just means scrutiny. Has anyone ever asked the simple question what's the best way to spend $3.5bn on transport for Akl? If they have did the CRL come out on top?

The whole thing is so piecemeal. This business case largely depends on the economic viability of other future investments which in turn will only make sense if they get to use the CRL for free. Has anyone taken the time to lok at the revised AUP and ask whether the CRL still is the best transport investment given the likely future form of the city?

Donald all transport spending on new projects is a bunch of voodoo economics to appease whoever is the Minister. None of the RoNS projects had a business case and they cost 5-10 the amount of the CRL. They are a great big election bribe to National's Moar Motorways constituency. It was such successful tactic for several general elections National tried it for a by-election too.

Remember National's 10 bridges for Northland, which mysteriously appeared and disappeared in importance according to electoral need. Winston has been asking since January what happened to them

The fact that the CRL project got the go ahead despite opposition from the several Transport Ministers -Brownlee and then Bridges shows it had something going for it.

A transfer of wealth from the rest of the country to owners of CBD properties? That would fit well with the current government's usual policies.

True. But this a general problem -how to invest in the built environment to improve amenities in a way that does not get capitalised into property values. In other words how to stop a wealthy subset of society from taking the exclusive benefit of public decisions/spending which should be for the inclusive benefit for everyone in society.

I have long considered this question - my byline on Twitter (@brendon_harre) is -Trying to optimise amenity and affordability values for urban areas.

The article -"Where do Upzonings happen" -does some economic analysis on NIMBY neighbourhoods to get some understanding of this effect. It has some interesting findings.

"What NIMBYs are really after is limiting access to neighborhood amenities, mostly by limiting the quantity of housing. Neighborhoods (at least the ones empowered politically) do their best to hold housing below the market-clearing quantity. This ensures that the value of neighborhood amenities is capitalized into home prices. Without quantity controls, the “nicest” neighborhoods would be the densest. Instead, thanks to zoning, they’re simply the most expensive. There’s a steep premium for buying into the neighborhood club."

Len who?

No grandiose legacy in schemes like this. "The benefit is clear for Summit, which now can forgo massive capital expenditures on a new parking lot it would otherwise need to build and maintain. Instead, it can pay a fraction of that amount to shuttle people to and from the train using Uber. Rogers told BuzzFeed News that he expects the deal will cost Summit only about $167,000 annually, a far cry from the likely $10 million it would cost to build a parking lot — plus, Summit doesn’t have enough idle land downtown, anyway."

All my life I have been reading about this line. Well overdue. The old green trolley buses then were great. But that was then.
That cost is also only a drop in the bucket for what is needed. In rail alone think airport, think Onehunga - Avondale. For North Shore think driverless cars (thanks DC) with purposebuilt trunk routes and tunnels.
To build what a modern city needs don't think $4billion, think $100billion.
I'm no longer an Aucklander but if the place is the economic powerhouse it claims to be then they could increase rates by ten time (yes x 10) and start.

What a lot of people in Auckland and outside fail to understand is that Auckland is no longer a big town but it is rather a city (a small one). This means big town solutions will actually make things worse, i.e., more roads. The days of driving into town is over - the sooner we realise that the better. Then we can actually have a city centre that is functional and nice to live, work, and play in.

the original britomart, done brilliantly by Les Mills, was funded by commercial property sales resulting from traffic flows out of the development. the reason the council needs so much money for this new development is their proposals don't add up. time savings can't be covered by fares, gains from rising property values will be privatised, costs are far greater than benefits. Need some new leadership at Auckland Transport, come on Phil Goff, lets see what you're made of

I truly hope I am wrong but the whole business case for the CRL is built on dodgy numbers. You can not believe any of the studies completed by the council that have been put forward in this article. The governments own numbers didn't agree with councils.

The cost to build it has already gone from 2.5 billion to 3.4 billion.

The annual loss after its built will be far more than what is prescribed in the figures because they rely on tens of thousands more people using this must mean that tens of thousands more jobs will be created in the city, or the trains will start going to more places. Neither of which is likely.

Our children and grandchildren will still be paying interest on the loans to build it yet it will not benefit many of them.

Well done Len, your legacy of debt will be what you are remembered for and the CRL will probably be the white elephant that represents it.

Predict it will end up closer to 10 billion; apparently from an engineering perspective it can be done, but is super difficult.From a business point of view the number of contractors able to do such stuff is very limited, so with no competition the tenders will go sky high.
If CBD wants it CBD should pay for it, and carry all the risks; should be no problem if it is actually really viable economically rather than just a (Maoist) Great Idea, from a Great Man wanting a legacy.

..surely at such costs it must be getting closer to just putting on hundred and hundreds of free buses at peak hour? We have a motorway/roading sytem that can actually cope..the problem is its being utilised in a most inefficient way.
So instead of re-allocating how it's used, we feel rich enough to throw billions at another option. Has anyone crunched the free bus numbers as a comparison?

How about an analysis of the East-West link business case, current cost of $1.8 billion? That's more than the Waterview tunnels.