A big day yesterday with Auckland Transport officially deciding to drop the option of heavy rail to the airport in favour of light rail (LRT) or perhaps even buses as had been foreshadowed in the Herald in the morning but also hinted at for some time from previous information released by AT.
Yesterday afternoon they released the previously confidential paper that was used to justify the decision which has thrown up a few interesting details.
In the end the biggest nail in the coffin for heavy rail has ended up being the cost which is now estimated at $2.6 to $3 billion. Being even more expensive than the CRL and with fewer benefits – after-all the CRL improves the entire rail network – it is always going to be hard sell and in the end AT and the NZTA have said it simply offered “low value for money” with a Benefit Cost Ratio of 0.37-0.64. As a comparison they estimate LRT could have similar or even greater overall benefits – I’ll get to that soon – but come in at less than half the price at an estimated $1.2-1.3 billion giving it a BCR of 1.11-1.72. That figure seems to be an improvement on earlier information such as the video that was released at the beginning of the year.
The biggest issue with the LRT option though is it assumes that LRT will already be in place along Dominion Rd and that this is therefore just an extension. The issue with that is so far there is no agreement from the NZTA or the government that the Dominion Rd route will be supported – although the ATAP report last week seems to confirm something more than just more buses will be needed. But even if the cost of LRT along Dominion Rd (estimated at $1 billion) was included in, it still comes in cheaper than heavy rail and would have even higher benefits. The LRT option also benefits from providing new connections on the isthmus to the South West so represents a greater expansion of the rapid transit network. A comparison between the accessibility of the two is below.
The estimated costs and benefits discounted to 2015 $ are shown below.
On the costs, one expensive part of heavy rail is the need to also upgrade the Onehunga line and deal with the level crossings. AT say they considered three options for this, a long New Lynn style trench, realignment via Mt Smart and elevated rail with costs ranging from $458-578 million. Later it appears a low cost option of closing two of the level crossings and barriers which would cost $155 million and that was used in the Indicative Business Case but AT are also concerned not grade separating the crossings would cause traffic issues.
Within the airport they also eventually came up with a more direct route shown in blue but that requires bored tunnels ~20-25m deep and adds to the costs listed above and is what pushes the cost to $3 billion. There are other issues too such as with the terminal station under the airport, AT would have to pay for it when the Airport wanted to upgrade the terminal which is likely to be sooner than when AT have LRT scheduled and that would add $100 million to ATs already tight budget requirements.
The paper also addresses many of the issues that have been raised on here and in other places in the past.
One such issue is the travel time and people have in the past questioned suggestions that LRT could be the same or even faster than heavy rail. They say travel times were worked out using several models taking into account issues such as LRT speed down Dominion Rd, the acceleration/deceleration possible, station dwell times, specific track lengths, curves and gradients along with how fast vehicles could travel over them. They say that because of the heavy rail geometries required there is only a few locations where HR can hit top speed.
All of that resulted in the range of times shown below from both Aotea and Britomart with LRT coming out on top from Aotea which is centre of the CBD.
One particular area where LRT is much faster is in and around Onehunga, presumably the section over the harbour where the line has to be elevated above Neilson St then again over the East-West mega road before dropping under the motorway bridge as shown below.
The big concern for me with travel times is that it comes down to how well they’re implemented and so far AT haven’t proven themselves good at at that. This is evidenced by how poor AT have seemingly been so far at addressing our slow trains.
Another issue that has been raised before is the capacity of LRT. What needs to be remembered is that even before this idea came along, AT aren’t planning on dinky little streetcars running around the suburbs but are large, long and potentially quite fast. As AT have said in the past they could be up to 66m long carrying over 400 passengers each which is on par with our current electric trains.
So over a two-hour morning peak with services every five minutes LRT could be moving up to 10,000 people an hour in each direction which is about the same number of people who currently arrive at Britomart each morning and nothing to sneeze at. They say the model estimates that with LRT around 3,500-7,500 people would cross the Manakau Harbour each morning with around 5,300-6,900 using the section from Onehunga to Dominion Rd. The biggest concern would be that if it was too popular it might restrict capacity on Dominion Rd but in many ways that would be a nice problem to have.
One interesting aspect of the paper is a discussion on the opportunity cost of Heavy Rail. While it doesn’t happen in reality, they say the hypothetical situation of taking the money saved by using LRT would be enough to also build a light rail link from the Airport all the way to Botany – whereby it could link with the proposed AMETI busway. I don’t think that this route is a high priority to sink another $1b+ into just yet compared to other PT routes such as the NW-busway but it is interesting to ponder long term as part of a wider LRT network.
Here are the recommendations the board were provided which I assume they accepted. Given the capacity that has been suggested is needed and that we know there are already issues with bus capacity in the city I can’t see a bus option stacking up other than for some short term improvements.
- That Management discount heavy rail to the airport from any further option development due to its poor value for money proposition;
- Instructs Management to:
- a) Develop a bus based high capacity mode to the same level of detail as the LRT option to allow a value for money comparison with the LRT option and submit this to ATAP for consideration;
- b) Refine the LRT option further to address the high risk issues as articulated in this paper;
- c) Report back to the Board on the findings of the bus based high capacity mode and LRT comparison.
- d) Progress with route protection for bus / light rail, not heavy rail;
- e) Align the SMART and CAP business cases to enable the consideration of an integrated public transport system between the city centre and the airport
- f) Progress the business case development of the RTN route between Botany, Manukau and the airport and align this with NZTA’s business case development for SH20B.
The decision between light and heavy rail will never please everyone but personally I’d rather a light rail connection that actually happened than a heavy rail one that never did. A bit of a case of don’t let perfect be the enemy of good but in this case it’s not clear that heavy rail is perfect. I also don’t think it’s realistic to think that it’s just a political change away from the decision changing like some have suggested. I personally can’t see other political parties agreeing to fund something with such a poor business case given the alternative option that now exists. We’ve been critical of road projects that have poor economic cases so it’s only fair that we do the same with PT projects (although do wish these road projects were subject to greater levels of scrutiny – looking at you East-West).
What is needed though is to simply get on with things. We can’t afford to wait another 15+ years for this to be built, we need to be getting on with it. Compared to some of the motorway projects which now get accelerated rapidly, major PT projects like this seem to languish in the back of the planning departments for years, if not decades. This needs to change if Auckland is to become a much more liveable city.