Friday certainly turned out to be interesting following on from our post from that morning that the NZTA now supported Light Rail along Dominion Rd and to the Airport in the future. The council pulled down the document our post was based on, which was a waste of time given we’d already published our post. Later in the day, Transport Minister Simon Bridges confirmed it all, followed by a joint release from Auckland Transport and the NZTA. While it’s great that we’ve now got the government saying that a rail connection to the airport will happen, the idea of it being 30 years away has been met with ridicule from a lot of people.
One of the first things I found interesting was the different way in which the agencies described the decision compared to the one from the minister. Most notably Bridges seemed to make more of an effort to talk up the recent Advanced Bus Solution study (ABS) and the ability of buses to cope with demand for the next 30 years.
The study found an advanced bus option could provide a credible solution over the next 30 years that could progress from the current bus-based system to a long term solution.
The study also demonstrated the advanced bus option has the potential to deliver on forecast demand depending on the rate of growth of the city.
A lot of the timing so far seems to be dependent on just how much capacity can be eeked out of buses before an upgrade to light rail is needed and that’s where the ABS study comes in.
As I mentioned on Friday, the ABS was commissioned by the NZTA following on from the Auckland Transport Alignment Project (ATAP) which only referred to some key public transport projects as ‘Mass Transit’. The NZTA describe the objective of the ABS as coming up with the preferred bus based option for between the city and the Airport and serving the central isthmus, utilising new and emerging technologies, and that is able to be compared with some of the previous studies that have ultimately recommended light rail as the solution.
The ABS study was also released publicly on Friday finally giving us the opportunity to look through it. As mentioned on Friday, the recommended the same route down Dominion Rd then along SH20 as the previous studies that recommended light rail have. It also recommends a rapid transit corridor for buses of the same width and location within the road corridor as is needed for light rail. This is why the announcements on Friday afternoon talked about getting on with route protection. Unfortunately, it didn’t take long to find some gaping flaws and major concerns.
The ABS also has another option that uses a second corridor between K Rd and Onehunga, going via Newmarket and Manukau Rd. For the purposes of this post though I’ll stick to just the Dominion Rd corridor.
To service the route from the airport to the city the ABS suggests 4 separate service patterns that they say will need to operate. Each service would operate at four minute frequencies and calls for a mix of new, 18m long articulated buses and double-deckers. The four routes are
A – an 18m articulated ‘all stops’ service from Mt Roskill Junction to Mt Roskill Junction via Britomart
B – an 18m articulated ‘all stops’ service from the Airport to Airport via Britomart
C & D – two double-decker ‘express’ services from the Airport to Airport via Britomart, only stopping at the express ABS stations
Four different services at four minute frequencies, that’s 60 buses an hour down Dominion Rd and Queen St and something that would present a number of challenges including:
- Express buses would need to be able to pass all stops buses if they are to have any time advantages. Unlike the Northern Busway stations which has four lanes at stations so buses travelling straight through can pass. The ABS envisages that the express buses will pass all stops buses by driving onto the other side of the busway. Buses at high frequencies in each direction weaving in and out of lanes sounds like a safety case nightmare.
- There are many key intersections along the route. Major intersections, such as at Balmoral Rd, can have signal phase cycles of over 2 minutes meaning that these buses are ultimately going to bunch up and become less reliable. To help counter this, the ABS assumes there will be significant levels of signal pre-emption to prevent buses from falling behind schedule. Signal pre-emption can work well when frequencies are a bit lower, like as is proposed with light rail, but the frequencies suggested for the ABS would create significantly less opportunities for alternative traffic movements, including cross town buses.
- This is even more critical in the City Centre, especially where it intersects with Wellesley St, which is expected in the future to be a 4-lane busway moving over 140 buses an hour. The ABS glosses over this and only suggests other isthmus buses could be turned into feeders for the Dominion Rd services.
- Things get even more tricky at the Northern end of the route where the ABS expects buses will turn around by looping around Customs, Lower Albert, Quay and Commerce Streets before heading back down Queen St. As a reminder, they’re suggesting 60 buses and hour would be doing this, half of which are double-deckers and the other half longer, articulated buses. It’s unclear what impact this would have on buses like the Northern Express which uses Lower Albert St or the busy Mt Eden Rd buses which start from Commerce St. It would also require retaining at least four lanes for traffic on Quay St, working against council plans to make the area more pedestrian friendly.
- The ABS also suggests using Commerce St and Quay St as a place where services could layover between runs. As above this would impact on Mt Eden Rd buses and it would also appear to block access to the shops directly above Britomart.
- Speaking of pedestrians, compared to the light rail option, with 60 buses and hour in each direction it will make it much harder for pedestrians to cross roads. This would be both in the city centre or on Dominion Rd as on average there will always be a bus in some direction 30 seconds away.
For a lot of the points above, they seem to have just explained away the challenges by suggesting technology will solve it. Some of what they’re suggesting sounds reasonable but I’m not aware of having been fully implemented anywhere in the world yet.
All up, it seems the authors of this report, and their clients at the NZTA, completely forgot/ignored ATAP when it said we can’t continue to stuff more buses in the city centre and proposes to solve problems by stuffing more, only slightly larger buses in the city centre.
Another important element in all of this is the cost. The ABS Appendix suggests that the standard Dominion Rd option, with contingency, would cost $1.132 billion to build. On top of that there would need to be an additional $70 million for the buses – 47 articulated buses at $800,000 each and 51 double-deckers at $600,000 each. That brings the total to about $1.2 billion.
That is cheaper than Light Rail, which from the city to the airport is expected to exceed $2.4 billion but it’s also important to take into account the operating costs(OPEX) – and 60 buses an hour would require a significant number of drivers compared to LRT options.
Interestingly the ABS study is only assessed over a 20-year period while most studies these days cover a 40 year timeframe. Even so, the OPEX is significant at almost $1.5 billion.
By comparison, the SMART study that previously recommended light rail to the airport suggests OPEX costs of $790 million but that was assessed over 40 years. Given SMART only looked from Mt Roskill to the Airport, assuming those costs increased by 40% to account for getting to the city, it will likely be cheaper over the long run to build LRT from the start.
To top it off, light rail could have considerably larger capacity. AT’s plans for light rail would see two 33m long vehicles carrying 225 people combined to carry 450 people vehicle every four minutes in each direction which is higher than the ABS option. However, many cities with modern light rail systems, like Seattle, are starting to go further and so it’s possible we could ultimately end up with 99m long vehicles carrying 675 people. That’s potentially over 10,000 people an hour, 40% more than the ABS option.
Overall this seems to be a report that’s high on theoretical solutions but that is unworkable in the real world. I guess that’s why the AT/NZTA boards say further work is needed to determine the best point to transition from bus to light rail. There are of course some sensible improvements that can and should be made now to improve buses on this route but it would be foolish to spend billions on CAPEX and OPEX just to have to do much of it again to upgrade to light rail in the future.