With the change in Government, we are likely to see PT/Walking/Cycling prioritised over the many roading projects National wanted. However, it is likely and in some circumstances necessary for Government to make some investments to take place in our strategic roading network during the first decade 2018 – 2028.

Red- Current and Future Strategic Road Network for ATAP under the previous Government

I think it would be best to start by saying first I am not anti-roads I just believe:

  1. Investing in cycling/walking/buses is investing in roads as they increase corridor productivity;
  2. That induced demand in growing urban centres is empirically true, thus roading projects need to be judged beyond fictional travel time savings that never eventuate beyond the medium term, even though this makes up most of the benefits in business cases;
  3. Specific roading projects like bypasses allow us to prioritise road space on other streets for placemaking, active modes etc. this is something we have been traditionally poor at;
  4. That we have a relatively mature strategic roading network, it makes sense that the investment scales tilt back slightly towards our PT/Active modes networks to clear the large infrastructure deficit we have due to the historical underinvestment;
  5. That until we understand how pricing will drive mode share, trip and travel time shift investing in roading capacity improvements we may not even need would be foolish;
  6. Safety upgrades are a very important roading investment that needs to be made, not just because it saves lives and prevents injuries, but provides resilience;
  7. Lastly that many roading projects proposed are heavily gold plated when for a fraction of the cost we could deliver much of the capacity and safety benefits. The opportunity cost of gold plated projects are not great for the roading network either where because all the funding is directed at a few areas much of network misses out on essential upgrades especially around safety;

So what strategic roading projects are likely to be built:

East West Link 

It is likely that East West Link will be built however, it will be a scaled-back version delivering much of the benefits at a fraction of both the environmental and financial costs. I would suspect it would be similar to Option B.

Option B

We have already seen significant improvement that has solved much of the problem in the area with the cheap $15 million preliminary works which included

  1. Widening SH20 from 3 to 4 lanes in each direction between Neilson Street and Queenstown Road;
  2. Lowering the rail bridge and replacing with a new, lowered road at Neilson;
  3. Creating four lanes between Alfred Street and Angle Street;
  4. Dedicated bus lanes on SH20 between Rimu Road and Walmsley Road;

I suspect the new programme will be more of this really cheap upgrades such as

  1. Further upgrading Neilson, most of Neilson is really wide but only line-marked for one lane each way. I mean residential suburban arterials have a higher capacity layout than this even though its one of our major arterial serving one of biggest industrial areas in the country, it’s so odd;
  2. Upgrades of Church Street;
  3. Fixing the SH20 interchange which alongside the problems near the overbridge seemed to be the cause nearly all the problem in the area;
  4. An interchange at the SH1 end.

All in all, we are likely going to be able to fix most of the problems in the East-West corridor with a package of hopefully less than $600 million rather than spending $1.25 – $1.8 billion. It also means not harming Panukau’s urban transformation plans for Onehunga as well as not causing environmental/social damage severing Onehunga from the harbour.

Southern Corridor Improvements 2.0 

At current the NZTA is widening the Southern Motorway from Manukau to Papakura which does involve fixing the dangerous Takinini interchange. With massive greenfield growth slated for south of Papakura as well as the heavy industrial planned in Drury and the overbridge likely to be raised as part of the likely electrification of the line to Pukekohe, I think it is highly likely the Southern Motorway will be widened from Papakura to Drury, this alongside an upgraded motorway interchange which will cost around $300 million.

SH20A – SH20 Southbound Ramp 

At current the SH20/SH20A interchange is missing a leg meaning that you cannot access SH20 Southbound coming from the Airport. What this means is people are using Massey Road instead. Adding the missing leg will free up Massey Road for Cycling/PT improvements and the project is estimated to cost between $100 – $150 million.

SH20/H20A Interchange

But if we do build this we do have to make sure we do upgrade Massey Road for cycling and PT, not leave it as a rat run with no improvements.

Northern Corridor Improvements 

The Northern Corridor improvements will go ahead as planned for around $700 million. It isn’t a bad project overall pretty multi-modal and was recently approved by a Board of Inquiry.

It will:

  1. Complete with Western Ring upgrading the last section of SH18 to motorway with a new motorway-motorway interchange between SH18/SH1. It will however not include an SH18/SH1 citybound ramp so not to encouraging Upper Harbour traffic onto the Northern Citybound.
  2. Extending the Busway to Albany with a separate project adding a new busway station at Rosedale;
  3. Walking Cycling Improvements;
  4. Widening sections of the Northern Motorway.

SH20B Widening

ATAP had $200 million to widening and presumably upgrade SH20B into full motorway standard. I hope this is one the Government re-thinks and instead prioritises Bus Rapid Transit for the corridor.

SH18/16 Interchange 

I think it is also likely that we will see the estimated $234 million upgrade of the SH18/SH16 interchange allowing direct motorway to motorway connections between SH16 north of Westgate and SH18.

Current SH16 /SH18 Interchange

To be honest, many of the first-decade strategic roading interventions in ATAP really didn’t worry me too much, its the more local stuff. Its the billions upon billions of dollars in arterial roads, and parallel mini expressways etc. for Transport for Future Urban Growth which concern me more.

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31 comments

  1. I’ve always wondered why they haven’t 4 laned all of Neilson Street, but the other day when I saw a truck trying to turn right out of Toll I realised that 4 laning would make this almost impossible.

    1. I agree with your concern. We would need to look at making all driveways left in/left out only and formalizing some turn around opportunities, likely using side roads rather than turning bays.

      1. That said the entire Northern Corridor Project is $700m and that is for a full motorway with those motorway flyovers along with a busway and 3 new bridges. $600m does sound to be quite steep still to widen a road, put in some traffic lights and build one motorway flyover. I would expect it to be more like $300-400m.

          1. True, you would probably underground utilities and replace water infrastructure at the same time. All adds cost….

  2. Similar to the argument above about northern corridor improvements and not including an SH18/SH1 citybound ramp so not to encourage Upper Harbour traffic onto the Northern Citybound, I don’t think SH20/SH20a interchange needs money spending on an airport to southbound connection, due to SH20b

  3. Surely we don’t really want moar roads? The WHO recommends 20% investment in active travel. We are still looking at 1%. Until there is a network of protected network of bike and bus lanes, really not seeing the value in making the roads ‘better’.

    1. Alistair, I completely agree with you. Surely the starting point should be, what modal share do we want for cars? Vienna, currently at 27% wants 20% by 2025. So everything is driven from this starting goal. Car parking prices have been increased and by Auckland standards public transport prices are ridiculously low.

      Where is Auckland sitting? 80% car mode share? The same or slightly less spending on roads is going to produce the same result we have now – more cars, more driving, more congestion.

  4. AT hasn’t updated their Northwest transformation page since late 2015. https://at.govt.nz/projects-roadworks/northwest-transformation/

    I’d like to know when Northside Drive will extend over the motorway and connect to Trig Road. Hopefully this will be built at the same time as the SH16/18 interchange.

    Also when will Brigham Creek to Hobsonville Road be upgraded? There was a fatal accident at that intersection last month, and traffic is increasing with population growth every day.

  5. I work on Neilson Street, near the Metroport intersection and have some ideas that would make huge improvements.

    The rest of the road should be 4 laned immediately. This would like require under-grounding of some power poles, and even if they just turned some of the on street parking into a marked clear way would be an improvement. There is also room along the southern side to add a decent shared path. I do bike to work occasionally, and the whole East end of Neilson and most of Church street is very cycle / pedestrian unfriendly.

    The church street / Neilson intersection should be reconfigured to make Neilson Church st the priority. Often in the evenings, Neilson will be backed up to Waikaraka park, when Church street is not that busy. Some improvements to light phasing might help in the shorter term.

    The biggest issue is the western end motorway interchange. I believe the biggest problem is that all the northbound off ramp traffic has to cross paths with the traffic heading to the motorway at Neilson / Onehunga mall road. I’d like to see two bridges built similar to the Waterview connection ramps which would make a huge improvement here. It would also mean only local traffic heads to the wharf area, opening it up for development.

    I have no idea what to do at the SH1 end of the project, I live in Ellerslie, so try to avoid it..

    1. The western would be easier to fix than that – it just needs a left turn slip lane for those heading north on SH20. This will mean that only those heading south will need to pass through the Onehunga Mall lights, probably half the number. I always assumed that was the purpose of getting rid of the overbridge, I was amazed when they only put 2 lanes back in.

    2. Re shared path, Neilson isn’t a great pedestrian environment and is only going to get worse.

      I’d prefer a shared path from Onehunga along Princes through to Alfred and across Neilson to get you to Waikaraka Park and on to the Mangere Inlet shared path for more distant eastbound destinations. Some corridor acquisition to get between Princes and Alfred, and if additional signals at Alfred-Neilson would cause too much outcry then a ramped pedestrian bridge would also do the job – there are fairly long stretches of drivewayless space on both sides of Neilson for the ramps.

      1. That isn’t much use to people will work on Neilson Street. All roads are cycling roads we won’t get perfect on every one, but we should expect a shared path as aminimun on roads with 10000+ jobs

        1. Could you post an idea of a safe cycle network for areas like Neilson St, SB? The mind boggles … making me wonder if industrial areas should be designed like the old Omaha – roads with no footpaths, back networks for active modes. But they weren’t, and yes, people need to get to work. What on earth will work?

  6. This is a huge topic (and a fine first effort!). I woudl say in general terms that we shoudl focus on having a safe, complete and connective road network first, and worry about road traffic capacity second. Where there is no road alternative build a new road by all means. that includes your bypasses. But don’t plough a lot of money into road widening and capacity upgrades etc until we are sure there is no walk/cycle/PT alternative, and we have a safe system for peds and cyclists as well as cars.

    The economic case for road widening is often over blown. Outside peak hour, most roads only need half their capacity, and freight and business deliveries can move around fine then.

  7. The problem with the SH1/SH18 interchange is they have left out the two ramps that would made the Western Ring Road a ring road. That means the SH1 northbound to SH18 (which is currently the dangerous one since a queue regularly forms onto the through lanes of the northern motorway) isn’t included. Second the SH18 to SH1 southbound is the movement that they don’t wont to encourage. But it is already being done in both peaks by people from West Auckland who travel to and from Takapuna. NZTA has had a little dose of AT’s CBD centric thinking. Until they build these ramps they can’t claim it is finished.
    But the worst part is that leaving these ramps out means they can make the Upper Harbour to and from Constellation Drive into a secondary link that has to go through some really dumb loops. These are actually the two most important movements. The two movements that this interchange was actually built for. Unfortunately this is what happens when there is nobody lobbying for the local part of the network. AT should have taken that role from NSCC but they have simply been absent. And NZTA? Well if it doesn’t start and finish on a state highway then they just don’t care.

    1. NZTA have designed the upgraded interchange so that ‘missing’ interchange ramps can be added at a later date

      1. Harriet, I thought your analysis was good up to this appalling sentence: “it makes sense that the investment scales tilt back slightly towards our PT/Active modes networks to clear the large infrastructure deficit we have due to the historical underinvestment;”

        Slightly will never cut it. There is just so much investment needed in PT infrastructure to catch up. An example is the 4 billion the government is allocating for light rail. That’s not going to fix every single issue. It obviously doesn’t address any PT issues on the Shore. It doesn’t address SeaPath. The extra petrol levy raising 150 million is inconsequential in terms of addressing the problem.

        The other major issue is that by world standards our public transport is expensive. The only way to address this is by an AT subsidy or a decrease in the farebox recovery by Government. Again a slight tilt towards PT investment just won’t cut it.

    2. The existing road (between Constellation and Paul Matthews) will become a local road that is a lot less busy. So the queues coming off SH1 Northbound should have an easier time getting onto that road westbound reducing those queues. Similarly in the other direction heading onto SH1 southbound. Yes it will keep traffic on this local road which is often referred to as Constipation Drive due to the congestion but hopefully it reduces the amount significantly (especially for those heading to/from SH18).

      1. No not a lot less busy at all. That is the problem. The two new ramps only remove one critical movement from the existing interchange- the right turn off from the north. The left on north has almost no impact on the interchange itself. The reason it won’t improve greatly or add much capacity is that the other movements at the intersection carry more traffic. The two throughs are very big, the right off from the south is big and even the left off from the south becomes critical when it blocks onto the motorway itself.

        Then they expect the higher flows on the existing road towards Paul Matthews to go through new intersections that don’t presently exist so the two lesser movements can have free flow.
        I get their strategy, it is just a pity it isn’t informed by some very basic traffic engineering. (And here was me thinking that doing the wrong thing really well was the preserve of AT).

  8. “That until we understand how pricing will drive mode share, trip and travel time shift investing in roading capacity improvements we may not even need would be foolish;”

    Yes, and this is why a strong public commitment to road pricing from the government is important. Even if it doesn’t get implemented for a while, it should be factored into investment desicions.

  9. We need a carbon tax. Sufficient to be used to offset the cost for low income families. We need it now. We need to think about the affects for our children and grandchildren. Much of our present infrastructure will not be appropriate by the end of the century. Unless we drastically reduce our emissions then sea level rise will make a nonsense of much of what has been built in the recent years.
    If we are to become a denser populated city we there is a need to plan our developments to take into account changes that are going to come and building like we did in te 70’s is not going to be appropriate.There needs
    We must change the way we are going and not give so much credence to the naysayers of the oil industry that we have seen in the last few days, like “NZ Oil and Gas” Andrew Jeffries et al.

  10. There was talk a short while ago regarding road safety and reduced speed limits. Is there any further news on that topic?

    I think that the variable speed limits on UK roads with the reduced speeds moving more vehicles per hour during peak flows actually moves more vehicles, is that correct?

  11. Thanks Harriet, good post. I agree with Sock Puppet that we need a “safe, complete and connective road network first, and worry about road traffic capacity second” and with Taka-ite pointing out that “slightly” tipping the investment back towards our PT/Active modes is woefully insufficient.

    At this stage, after so many decades of roads-first, investment needs to be decided by stated goals in safety and modeshare. The only roading projects should consist in reallocation of space to PT and active modes.

    If the road projects you’ve listed are important, they’ll still be important after a decade of reallocation and safety works, and we can do them then.

    And yes, your parting words about the billions to be spent on the roads for Transport for Future Urban Growth are so true. The induced traffic and car dependency from these roads will undermine measures throughout the city to reduce traffic and car dependency. It’s knock your head against the wall stuff.

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