Clearly this or the other versions that date from 2010 are not the current versions NZTA are developing now, but until new versions are released these are still worth looking at in some detail as neither the various physical constraints or the overall aims that drive these options have changed. The options can be seen here.
Considering these there are several high altitude observations I think are important to begin with:
- This will be the most expensive urban transport project ever undertaken in NZ; claimed to be $4-$6 billion. Two to three times the cost of the CRL.
- Not least because of the massive cost it is extremely unlikely that both sets of tunnels and systems would be undertaken at the same time. They will be staged; one will precede the other.
- The road scheme is essentially a SH1 bridge bypass, and therefore optimises through traffic, however it does not make any new connection that is not currently available nor in fact any increase in capacity on SH1.
- There is little spare capacity in the CMJ for additional vehicles so the new connection will remain the current three lanes north and a reduction from four to three lanes south.
- Essentially the bridge becomes a massive on/off ramp for city traffic and unless and until the rail tunnels and line are built more buses on bus lanes across the bridge will be the PT part of the project.
Here’s the set of variations currently available for the city end, all versions involve four tunnels under Victoria Park [3 new ones]:
All schemes also involve massive new interchanges on new reclamations at the North Shore end with flyovers and multiple connections between crossings, not unlike the new interchange at Waterview currently being built. Like the outcomes for traffic on North Shore local roads, the impacts of this project will be neither small nor all positive north of the bridge. However for this post I just want to focus on the city-side implications.
Assuming the road crossing is built first, which is consistent with assertions by politicians and officials with phrases like it will be ‘future proofed for rail’, as well as the lack of any real work yet on a rail crossing, it is worth asking exactly where will the new traffic enabled by the extra capacity across the harbour go once in the city?
Because the new crossing plugs directly into the CMJ, three lanes in and three lanes out, and because there are no planned increases in capacity through the CMJ, nor any space for any without further massive tunnelling, in effect the new capacity will be all on the bridge, so coming from the Shore this new traffic will all have to be accommodated by just three off ramps [same in reverse heading north]:
- Cook St; with new direct connections through Victoria Park
- Fanshawe St, especially for buses on new bus lanes
- Shelly Beach Rd, and then on to Jervois and Ponsonby Rds.
None of these exits can accommodate any increasing in traffic well, or without considerable disbenefit, especially if that increase in traffic is large.
- Cook St is pointed directly at the heart of the city, so this contradicts policy of reducing vehicle volumes in the city centre and is likely to infarct daily at the peaks as Cook St is close and perpendicular to Hobson and Nelson Sts which serve the Southern and Northwestern motorway flows. Gridlock is likely at the controlled intersections unable to handle large and peaky traffic volumes to and from these motorways. Additionally land use in this area is changing and intensifying making it even less suitable for the high speed motorway offramp it already hosts.
- Fanshawe will have reduced capacity for general traffic as a multilane Busway will be required to take the increased bus volumes from the bridge, and anyway is already at capacity at the peaks.
- Shelly Beach Rd is a narrow residential street not suited to the high volumes and high speeds it already suffers from the bridge now. Furthermore there is no benefit and little capacity for the streets beyond Shelly Beach Rd, particularly Jervois and Ponsonby Rds for a large increase in vehicle volumes.
Nonetheless, here are the forecasts they have come up with, Shelly Beach Rd with a 63% increase, is basically filled with bridge traffic by 2026 and the new crossing:
20,300 additional cars modelled for Fanshawe + Cook St with the AWHC option (assume that is all day on a weekday?). Even at the best sorts of turnover that would require around 10,000+ new carpark places. The downtown carpark has 1890 spaces. So where exactly do we put six new downtown carpark buildings? And what six streets get sacrificed to feed them?
“The significant increase in traffic movements conflict with many of the aspirations outlined in current Council policies, strategies, frameworks and master plans.”
–P 65 Additional Waitemata Harbour Crossing Network Plan, NZTA, 2010.
Obviously these higher traffic volumes are not good for every pedestrian, resident, and general city user in these areas but there is one other group that this situation in particular is going to make miserable, and that’s the motorist. There is a word for all this additional driving everywhere on city streets: congestion. Yup this increase in capacity across the harbour may speed that part of the journey but it’s going to make arriving anywhere in the city in your car much more hellish than it is now. And don’t even think about finding or affording somewhere to park.
What NZTA’s consultants say about this:
The increased traffic flows through St Marys Bay on both Shelley Beach rd and Curran St look to lead to particularly poor and unfixable outcomes:
It seems optimistic to say that because there are cafes, and strongly increasing pedestrian volumes, on Ponsonby Rd, that drivers won’t try to drive there, especially if other bridge exits are controlled or too busy. After all the first rule of urban traffic is that it will expand to wherever it is allowed to go. So, in the end, taking measures to dis-incentivise drivers to use these exits, is the consultant’s advice:
It does seem kind of odd to spend $4-6 billion to increase capacity across the harbour only to then introduce other measures to try to stop people using it.
And it won’t be just parking, there’s also likely to be tolls, it appears the model says they can pretty much eliminate the traffic problem with an $8 toll!:
If only there was a way to enable more trips without inducing more and more cars to also be driven into the crowded city streets. After all the City Centre has been growing strongly without adding more cars most of this century:
In fact it looks like we are already at or even above the limit of desirable vehicle numbers in the city, and future developments like replacing car access to Queen St with Light Rail are likely to make even current numbers face pressure.
Additionally there is an issue with bus volumes as well as car numbers on the city streets, even though the New Bus Network, the CRL, and Light Rail, if it happens, will reduce bus numbers from other parts of the city, there is certainly a limit to the numbers of buses from the Shore that can be comfortably accommodated too. Below is the predicted year of maximum bus capacity at major entry points to the city. The role of the CRL in reducing bus number pressure from the Isthmus is obvious, so why not do the same thing for buses from the Shore?
So perhaps the answer is to reverse the assumed staging and build the rail Rapid Transit tunnels first, leaving space for the road crossing to come later. This certainly looks physically possible in the maps above. This would enable all of those possible trips across the Harbour that NZTA identifies to still be served but without any of the traffic disbenefits that so clearly dog the road only crossing. In terms of people capacity two rail tracks can carry twice the volume of six traffic lanes. Furthermore it can be built without disturbing the current crossing and its connections. And rail crossings have proven in the past to be good alternative routes in an emergency.
This would add the real resilience of a whole other high capacity mode across the Harbour instead of simply more of the same. It would make our Harbour infrastructure more closely resemble Sydney’s where most of the heavy lifting in terms of people numbers is done by Rapid Transit, as shown below. We already have ferries, buses, and cars bringing people across, isn’t it time we added the particular efficiency of electric rail?
It seems particularly clear that whatever we add next really can’t involve trying to shove ever more vehicles [cars and buses] onto our crowded city streets; that will simple hold everyone up.
All the information above was gleaned from the work done some six years ago for NZTA, from here, and Auckland has moved on a great deal from where it was then. Among other things that have been proven recently is that when we are offered a high quality rail system we will use it. We are also discovering the value of our City Centre as a place to live, and work, and just be in, and how this is only possible to continue this improvement with fewer cars on every street. We certainly believe that there are more options for a far greater Auckland than the simple binary ones studied above: the road crossing ‘future proofed’ for rail, or the ‘Do Minimum’ which is nothing.
So we have asked, as part of the Auckland Transport Alignment Process, for a Rapid Transit crossing as the next additional crossing to be modelled too. So we can compare the status quo with the road crossing, and with a Rapid Transit crossing separately. Additionally we know that AT are now working on how various rail systems could work so in time there will be properly developed rail options to compare with the road one.
There is time as well as the need to get this right, the Western Ring Route will begin to become more complete next year with the opening of the Waterview tunnels, and that whole multi billion dollar system is of course an alternative harbour crossing system and will alter both the performance of both the Bridge and the CMJ. Similarly decisions about AT’s proposed LRT system too has a bearing on options, as will the opening of the CRL next decade. Not least because the addition of these high quality systems will make movement through the city without a car much more common, as is the case in many overseas cities of Auckland’s size and quality.
The road crossing looks very much like an extremely expensive ‘nice to have’, that duplicates and tidies up the State Highway route, something to add when the missing alternatives have been built and there is spare budget to spend on duplication. Because on balance the road first additional crossing proposal really achieves little more than this: