Below is a plan developed by the Waitemata Local Board working closely with the Karangahape Rd Business Association to improve the area:
This is their accompanying text:
Over the next few decades the Karangahape Road area will experience a dramatic increase in growth, especially in the wake of the completion of the Central Rail Link. This will encourage many more people to frequent the area for shopping and entertainment – the creation of an entrance to the Underground rail Station in Mercury Lane would for example enable people from Avondale, New Lynn, and Henderson to easily travel into K Rd at night to attend theatrical performances at the Mercury Theatre . More people will live in the area as well.
In years to come the area surrounding Karangahape road will be inevitably rebuilt with higher residential units. A higher residential population is to be welcomed from every point of view – it will benefit the area economically and socially as well as improving the general environment ecologically by reducing commuting times and pollution. The increase in the number of residents in the area will probably bring a greater mix of people; at the moment there are few elderly folk or children for example but that may change swiftly after the completion of the CRL and more residential units.
The perceived and real safety and visual attractiveness of the streetscapes will be a crucial part of any development for the K Road area. In particular the volume and speed of traffic will need to be addressed. Karangahape Road is an important traffic route and the Business Association would not like bus routes (for example) to be rerouted away from the area, but certain things should be examined. Some roads in the area are prone to high traffic speeds as they have become to be virtually treated as part of the On‐Ramps for the Motorway System. These areas are very pedestrian unfriendly and it is vital that traffic calming solutions be implemented sooner than later.
This is an good summary of the challenges for the urban form of the area and the ideas on the map above are really good.
As the local board are calling for ideas for both K’Rd and Newton it would be good to get readers’ feedback on the suggestions so I’ll start the ball rolling with a couple of thoughts:
~The main entrance to the K’Rd station is planned for the top of upper Beresford St, this will involve the permanent closure of this road to through traffic [already restricted to one way onto Pitt St] and the creation of a public square around the station building which will be great, so the lower part of Beresford St will provide the road access to the buildings of Beresford and Day Sts. I find it strange the Business Association seems to be ignoring this. Only mentioning a Mercury Lane entrance.
~The connection of the abandoned motorway lane to Day St behind the old Rising Sun pub as well as to the new Grafton Gully cycleway and cyclelanes on Nelson St is a great plan. Also I think that the connection of Day St to K’Rd for traffic should be removed and this lane two-wayed back to Beresford. This should also link west across to Howe St under the existing bridge for a more direct and alternative route for pedestrians and cyclists.
~The narrowing of the top of Howe St would only be possible if the 020 bus is no longer fighting its way up that street.
~I don’t shared the Association’s enthusiasm for removing footpaths for on-street parking.
~Always yes to more street trees. But please not only palms, although I think the Nikau already on K’Rd are great.
~This area will see a rise in both residents and retail activity and the streetscape needs to improve with these changes. The CRL station will completely change the area; this will be Ponsonby’s station too [and especially Auckland Girls Grammar's], so the pedestrian amenity over the motorway should be better than just the narrow paths on the Hopetoun viaduct and the quality and liveliness of the Ponsonby/K’rd block will become more important. There is already a new major apartment building under construction in upper Howe St with surely more to come so perhaps something can be done to the terrible design failure of the block between Howe and Hereford Sts.
~Keeping the Link and other buses moving through here needs to kept in mind too. People from Ponsonby and other inner western areas will use these to connect with the much more useful and import rail system at K’Rd post CRL as well as to head into the City and Grafton and Newmarket as they do now.
~More and better pedestrian crossings are required. The really big elephant in the room with regards to traffic volumes, hinted at in the copy, is the motorway onramp at the K’Rd and Symonds St intersection. Without this ‘attractor’ traffic volume would surely be much more manageable through these city streets. I’m sure highway purists at NZTA would be happy to close this as the city onramps all affect the effectiveness of the system and its all important flow. These are signs of the strange hybrid network that is our urban motorway. Weirdly I guess the best chance for this being closed would be if the disaster of additional lanes across the harbour were built then pressures further into the system like this onramp would probably have to be cut simply to keep the CMJ from total infarction. What a horrible price that would be to pay however.
~ I like the ambition of caping the CMJ at the two high and narrow points, however I suspect the cost and difficulty of constructing the necessary serious engineering while keeping the m’way system below functioning makes these plans unlikely to be fulfilled. I do think however that cantilevering lightweight structures from the existing structures of the Upper Queen St, Symonds St, and K’Rd bridges on either side would almost certainly be both structurally and financially viable as well as architecturally exciting and offer interesting and useful commercial space; shops, cafes, and bars etc [great views- especially form the K'Rd bridge]. Like a 21st century version of the shops on Ponte Vechio in Florence or the old London Bridge! Or more prosaically like 21stC versions of the clip-ons on the Harbour Bridge. These would provide both weather and noise protection as well as interest for pedestrians and therefore go a long way to helping to repair the severance caused by the huge place-destruction of the motorway system.
~Great ideas on new parklets and re-forged pedestrian connections are to found on the map above too; these are necessary and affordable improvements that should be explored and made quickly.
~And AT really needs to come to the cycling party by giving over the outermost lane of the over-wide and over-fast Ian McKinnon Drive to connect Upper Queen St to the northern end of the new Grafton Gully route under Newton Rd. Here. Planters, maybe some barriers, a bit of paint, and a chat with their colleagues at NZTA to form the short connection under the Newton rd bridge with a two lane: Proper joined up off road network all the way from the sea to the heart of the west!
Let us know what you think.
This morning NZTA reported some run-of-the-mill snarfus on their big Auckland motorway system via Twitter, below
Matt took the opportunity to suggest they improve their communications to include more forms of transport available in Auckland, in particular the Rail network that they do help fund to operate [but weirdly are barred from funding new capital works on the rail network- even ones that would lower the net operating cost]. And this was their reply. Very good to see and certainly look forward to it becoming a reality:
Here’s the full conversation:
I also took the opportunity to help improve one of NZTA’s earlier tweets:
It would be better if my addition was able to more of a suggestion than quite so blunt and clipped but I ran out characters. Perhaps in order to be more concise on social media NZTA should just use a nice colloquialism like this tweeter last week:
Munted: that is both a concise and precise description of traffic in Auckland often, especially when it rains, or on a Monday, or a Friday or…. well anytime and for many reasons. Despite, or rather because of, the billions that continues to be spent on the motorway system. Time for the clever people at our ‘Transport Agency’ to be unleashed fully onto all modes and systems, not just State Highways, and not just in their communications.
Pretty much anyone who has driven along State Highway 16 in recent times would have noticed the massive amount of construction going on with almost half of the entire motorway affected by works. Once the St Lukes interchange upgrade gets under way soon then I believe every single trip along the motorway will be affected by works in some way.
The works are made up of a number of separate individual projects that all form part of the Western Ring Route. They include the St Lukes Interchange, the Waterview Connection, the causeway upgrade, the Te Atatu Interchange upgrade and the Lincoln Rd interchange. Most of these have only really visibly got under way over the last year or so however the last of those, the $100 million Lincoln Rd Interchange is has been going on for some time, starting in late 2010. That’s about 3½ years ago.
There has definitely been progress and we now have a massively oversized interchange that has been completed (I don’t have any photos sorry but you should really see the westbound off-ramp which is up to four lanes wide). As a side note, I understand one of the reasons the interchange is so big is that the former Waitakere City Council weren’t clear on their land use planning for Lincoln Rd (which is a disaster) so the interchange was basically designed to be as big as possible to cater for potentially massive growth. While most of the interchange itself has been completed, the work seems to be primarily focused on widening the motorway either side of it including the Henderson Creek and Huruhuru Creek bridges. Once those have been completed the motorway on either side will be three lanes each way plus there will be bus shoulder lanes.
Overall the NZTA say the project isn’t due to be completed until 2015 but here’s the thing, that’s quite different to what was said when they started the project. Back in 2010 they said in a FAQ with the press release.
Q: How long will it take?
A: Construction will begin imminently and will be completed by 2013.
So that suggests the project is running two years late. For what was meant to be approximately a three year project that’s quite a long time. That would also make the interchange project an almost 5 year ordeal and one of our longest motorway construction projects in history. So here is some information on just how long other massive projects have taken in recent times.
|Central Motorway Junction upgrade
||4 years 2 months
|SH20 Mt Roskill Exenstion
||3 years 9 months
|SH20 Manukau Harbour Bridge duplication
||2 years 4 months
|SH20-1 extension to Manukau
||4 years 7 months
||4 years 3 months
|Upper Harbour Bridge Duplication
||3 years 10 months
||2 years 10 months
|Victoria Park Tunnel
||2 years 4 months
||3 years 9 months
There are some very challenging projects on this list.
Now there could be some legitimate reason why it’s taking longer. Perhaps the NZTA deliberately decided to slow down the project so that it wasn’t completed so far in advance of projects like the Te Atatu interchange that it caused its own problems i.e. widening the motorway to three lanes could have been done but until the Te Atatu interchange is completed those three lanes would have just had to merge down to two anyway. Still there are some potentially good reasons for them to have finished earlier, in this case the extra lanes created could have been used as bus lanes in the interim helping to make up for delays caused by the closure of bus lanes elsewhere on the route.
The NZ Herald reports:
This afternoon Transport Minister Gerry Brownlee is expected to announce funding for two transformational roading projects. A $4 billion four lane motorway between Cambridge and Taupo, extending the Waikato Expressway a further 100 kilometres to the south and an $8 billion 50km motorway from Cambridge to Tauranga which includes a 14km road tunnel. Both projects were hinted at in the 2012 Government Policy Statement for Land Transport Funding. He will announce the projects at a ceremony to celebrate the extension of rail electrification into Britomart station.
“These are critical projects for improving freight efficiency in the North Island,” says Mr Brownlee in a leaked copy of his speech. “While we realise a near $12 billion investment in two roads that each carries fewer vehicles than the Kopu Bridge did when it was still one lane may appear to some as slight overkill, we think that those opposing the project just oppose progress and want us to return to dirt tracks and horse carts.”
NZ Transport Agency Regional Director Harry Wilson said his office was in celebration mode over the Minister’s announcements. “Once the Waikato Expressway project is finished in a few years’ time, we really didn’t know what we’d do with ourselves as we’ve lived and breathed that project for the past decade or more. We’re so pleased to see the government commit to the future of the Southern Waikato and Bay of Plenty regions – even though combined they’re not really growing – which will keep us in work for many years to come!”
Mr Wilson also noted that his organisation had been instrumental in pushing for the inclusion of the two projects in the 2012 Government Policy Statement and were “enthused” the project had been given funding approval. “We’ve learned a lot from our Wellington office in the past few years about the tactics of getting unnecessary projects in parts of New Zealand that aren’t growing over the line. We’re just so proud to have come up with the two biggest and most expensive projects ever imagined in New Zealand and now have funding approval for it!” Mr Wilson added.
Minister Brownlee noted in his speech that “Much like other Roads of National Significance, the Cambridge to Taupo and Tauranga motorways will duplicate an existing route where upgrades to that road could achieve most of the benefits for a fraction of the cost, but frankly upgrading what we’ve got is just boring – I want more motorways!”
Traffic counts between Tokoroa and Taupo on State Highway 1 show a slight increase in daily vehicle volumes from 6500 in 2009 to 6700 in 2013. Mr Wilson noted that “our traffic modelling suggests traffic volumes will increase to 60,000 cars a day in the next 5 years – almost all of which will be trucks!”
On State Highway 29 over the Kaimai Ranges traffic had also slightly increased, growing from 9200 vehicles per day in 2009 to 9300 in 2013. In the next five years this route is expected to increase to over 80,000 vehicles per day. The high number of trucks is said to be a key part of the decision to construct a tunnel under the Kaimai Ranges which was first investigated by the NZTA in 2010.
Local politicians unanimously supported the project when spoken to.
South Waikato District’s mayor Neil Sinclair said the projects would boost the economic productivity of his region significantly and wasn’t worried about the impact of the new motorway bypassing Tokoroa. “Look at Pokeno, it recovered a mere 15 years after being bypassed by the Waikato Expressway,” stated Mr Sinclair.
Taupo District Council’s mayor David Trewavas also stated his strong support for the project. “We’re about an hour and a half south of the thriving metropolis of Hamilton. This motorway will cut that time by at least a minute or two, which will be transformational to our economy. A local resident walking past added that they “didn’t care what was built, as long as it meant the money couldn’t be spent in Auckland.”
New Zealand Road Transport Forum chief executive Ken Shirley said the two roads were great news and would allow trucks to even compete better with Kiwirail, especially on the Tauranga to Auckland route. “Everyone knows that the wider population and other road users subsidising trucking is a great investment and these two projects will be great for that” he said.
Details of the project’s exact route, the timing of construction and how it will be funded have yet to be determined but when questioned, Mr Brownlee said he was optimistic the money could be found for such important additions to state highway infrastructure in the Upper North Island. “Hey we could always push that silly rail loop under Auckland’s city centre back a few more years,” Mr Brownlee shouted at reporters while leaving the airport for Britomart station in a Crown limousine.
A business case for the motorway projects is expected to be presented to Cabinet for funding approval next Monday.
A good piece from Campbell Live on motorway on-ramp lights which are something motorists love to hate.
I did have a bit of an issue at the end where the NZTA claim that traffic has grown over the last 5 years because as we know, that hasn’t been the case at many locations.
Like with public transport patronage, I keep a close eye on what are happening with traffic volumes on the motorways thanks to the monthly data released by the NZTA. The data doesn’t cover the entire motorway network but it does cover a number of key locations on it that can help to give an indication of what’s happening. I think the picture painted by these figures is extremely interesting. The sites we get monthly data for are:
- ALPURT (the Orewa to Puhoi toll road)
- Harbour Bridge
- Upper Harbour Bridge
- SH16 between Royal Rd and Hobsonville Rd
- SH1 at Panama Rd
- SH20 between Puhinui Rd and Massey Rd
- SH1 at Drury
- SH1 at Bombay
Excluding Wellsford, here are the six sites that we have the most data for
There are a couple of things interesting going on here. At most sites the traffic volumes continue to remain fairly flat and in the case of the Harbour Bridge the annual figure remains lower than it was over a decade ago. Another interesting trend with the Harbour Bridge is that the annual figure is now bouncing up and down between 150k – 160k per day (it peaked in 2006 at 169k). However you see a clear change in the SH20 site. This isn’t surprising as in recent years there have been significant extensions and changes to that motorway including the opening of the Mt Roskill extension in May 2009 followed by the Manukau extension to SH1 and Manukau Harbour Crossing duplication in August 2010.
The changes can be shown even clearer by indexing them to Feb 2010 which is the earliest the SH20 data is available from.
You will also notice that ALPURT has shown growth. Unfortunately what isn’t clear is if this is a result of total traffic volumes along the route growing or people becoming more comfortable with paying for the toll road and so a higher percentage of people choosing it over the free route. The NZTA previously to recorded vehicle volumes at Hatfields Beach would have allowed that comparison but stopped doing that at the start of last year when they handed the road over to Auckland Transport.
As mentioned, the graphs above don’t include all of the collection sites reported on, the ones missing being on SH1 North of Wellsford, on the Upper Harbour Bridge and on SH16 between Royal Rd and Hobsonville. I haven’t graphed them due to how low the traffic volumes are in the case of Wellsford and how little data there is for the other two (only two years worth). In saying that the data that is available is quite interesting in its own right.
SH1 North of Wellsford – Traffic volumes are very seasonal peaking over summer but overall they have been in decline since monthly figures began in September 07. This is quite important as we often get told that the reason behind the Puhoi to Wellsford motorway is to unlock Northlands economy. Both the SH20 and Upper Harbour Bridge sites are interesting as the annual figures show traffic volumes on those sections had been flat since 2003. The volumes over the Upper Harbour Bridge only started increasing again in 2008 after the Upper Harbour section of SH18 was completed while the SH20 site only started increasing in 2011 after the Westgate to Hobsonville section of SH18 was completed.
To me these figures show a couple of key trends. The motorways not widened or extended have shown little to no growth and in some cases volumes remain below what they were in the mid 2000′s. In the places where we have built motorways, vehicle numbers have been increasing. To me what this effectively points out is that changes traffic volumes are really just a reflection of what we’ve invested in, or in other words a case of build it and they will come. That might sound logical (and it is) but it also highlights the opportunity we have to determine just how much traffic is on our roads in the future. Build more roads like the current plans suggest and we’ll get more traffic.
Of course the opposite is true too, remove roads and traffic disappears with it. This has been shown quite well in Seoul, Korea where since 2002, 15 expressways have been demolished and more are planned. The most famous of which was in Cheonggyecheon where they removed an elevated expressway and ground level roads carrying over 150,000 vehicles per day and restored the original stream making a wonderful urban park in the process.
It went from this:
And the outcome was even more impressive:
- Traffic volumes dropped while bus and subway usage rose
- There were increases in fish, birds and insects in the area.
- Temperatures decreased and are on average 3.6% lower than other parts of Seoul.
- It became a centre for cultural and economic activity.
- And perhaps most interesting to the NZTA/AT, traffic speeds on other roads increased which is an example of Braess’s paradox
Now I’m not suggesting that we tear any existing roads down but more just highlighting that we have the ability to shape the city how we want it. If we don’t want traffic volumes to increase in the future that we should start by not building a heap more roads.
Life under the Victoria Park Viaduct
Photo is credited to oh.yes.melbourne
By now we’re pretty well acquainted with ramp signals on motorway onramps across Auckland. You know the ones:
NZTA explains the reasoning behind ramp signals on this old page (which hasn’t changed since the NZTAs predecessor agency over 5 years ago):
Currently traffic on the motorway is disrupted by ‘bottlenecking’. This means whenever traffic enters the motorway and then shifts from lane to lane, it creates a slowing pattern as vehicles back up behind the on-ramp entry zone.
Most accidents on Auckland motorways happen during peak hours when traffic is stop-start, due to lapses in driver concentration and motorists travelling down crowded on-ramps vying for positions in traffic or trying to merge together.
Ramp signalling provides a smoother flow of traffic, minimising stop-start conditions by separating on-ramp traffic into streams of one or two vehicles. Ramp signals are designed to keep traffic flowing on the motorway and to reduce accidents.
Early analysis suggested that ramp signals improved the throughput and reduced the levels of congestion on the motorway:
Data gathered since the signals have been turned on has given the following results for individual sections of the Southern Motorway (SH1):
Curran Street northbound
- Improved northbound traffic flows on clip-on lanes on Auckland Harbour Bridge
- 18% – increase in throughput of vehicles
- 12% – improved peak period travel speeds
Wellington Street northbound and Northwest – North/Port-North
- 6% – increase in throughput of vehicles
- 4.5% – increase in travel speeds
Hobson Street to Market Road southbound
- 15% increase in throughput of vehicles
- 16% improved travel speeds
- Commuter traffic cleared 20-30 mins earlier during afternoon peak periods
- Safer merging and motorway incidents being cleared up to 15 minutes faster, to restore normal traffic flows
Between central city and Ellerslie-Panmure, Mt Wellington and East Tamaki Interchanges southbound
- Peak period traffic flows have been significantly improved
- Shortened periods of congestion
- Motorway is carrying significantly more traffic during peak periods than before
- Travel speeds have increased
The big question with ramp signals has always been whether it just “shifts the problem” onto the local roads. When ramp signals were initially introduced, Transit NZ was an agency solely focused on the operation of the motorway system and didn’t really care what happened on the local roads. As long as the congestion wasn’t on the motorways then it wasn’t their problem. NZTA has (fortunately) taken much more of a one network/system approach to transport in Auckland than this and work very closely with AT in the day to day management of the network.
I suppose the big question is whether the improvements to flow on the motorway network are sufficient to counter-balance the additional waiting on onramps and on the local roads that lead to the onramps. But more deeply, I think there are questions around whether we want idling cars (and their pollution) on local streets where everyone else is, or confined more to motorway corridors away from where people live, work, walk or cycle. Do we really want to privilege long-distance trips (those already on the motorway network or who access it at more distant onramps where the ramp signalling doesn’t happen or is on a faster cycle) over shorter distance trips from more central locations who get stuck on really long queues at the signals? These are all complex questions.
My gut feeling is that ramp signals are probably a good thing on balance providing they are actively managed to ensure:
- they aren’t in operation when they shouldn’t be.
- they respond to problems on the local road network.
- any benefit to the operation of the motorway network really does outweigh the impact they have on the local road network.
However I’m not sure if we are currently getting all of those benefits, in particular the impacts on local roads. Some of those impacts are bound to part of the reasoning for monstrosities like Lincoln Rd.
The NZTA have awarded the contract for the “upgrading” of the St Lukes interchange and the widening of the motorway between there and Waterview. Here’s the press release:
The contract to construct the next stage of Auckland’s Western Ring Route – upgrading the Northwestern Motorway (State Highway 16) between the St Lukes Road and Great North Road interchanges – has been awarded to the Australian-based infrastructure company, Leighton Contractors.
The $70m project is jointly funded by the NZ Transport Agency and Auckland Transport.
A two kilometre-long section of the motorway will be widened from three to four lanes in each direction. There will also be improvements to the motorway ramps and the St Lukes Road -Great North Road intersection, while the St Lukes Road overbridge spanning the motorway will be widened to benefit drivers, walkers and cyclists.
The Transport Agency’s Highways Manager, Tommy Parker, says this is the last of six projects to connect the Northwestern and Southwestern (SH20) motorways.
“The upgrade is part of our programme to get our network ready for the increased volume of traffic when the Waterview tunnels connecting the Northwestern and Southwestern (SH20) motorways are completed in early 2017,” Mr Parker says.
Work is due to start in mid-autumn and be completed by late 2016. The other projects to connect the two motorways are the upgrade of the Maioro Street interchanges (SH20) which is completed, and the upgrade of the Lincoln and Te Atatu interchanges, the Causeway Upgrade Project, and the Waterview Connection, which are all under construction.
“Leightons bring plenty of infrastructure experience to the St Lukes project. The company is part of the Causeway alliance, and has been involved in some of our biggest Auckland developments including the Northern Gateway Toll Road and the Newmarket Viaduct Replacement Project.” Mr Parker says.
The Western Ring Route is a Road of National Significance, and will provide a 47km-long alternative to SH1 between Albany and Manukau. It will improve safety and city and regional transport connections for people and freight.
The project isn’t exactly a surprise as it’s been talked about for a while and was part of the overall Waterview consenting process that occurred a few years ago. In saying that it does once again bring into the limelight the claim often made (including in the last paragraph) that the Western Ring Route is about creating another route through the region when in fact this piece of work is all about making it easier to get from the airport to the CBD. This is even mentioned in the description on the project page.
The Waterview Connection project is one of the most important infrastructure developments ever to take place in New Zealand. Completing a motorway ring route around the city, it will unlock Auckland’s potential to become a truly world class city, combatting regional congestion and creating a direct, time-saving link between the International Airport and CBD.
The part of the project that is of most interest is the widening of the motorway bridge and the sections of Gt North Rd on either side. This is especially the case as the NZTA and Auckland Transport were at one stage looking to wipe out the large mature Pohutakawa trees that line the road so they could create one additional lane all in the aim of appeasing the gods of traffic flow. This is the before and after of what they showed to the local board a few months ago and which the board weren’t happy with.
The images below suggest they may have backed down on that though. As for what’s now going to be built, the NZTA say that the project includes:
- 3 lanes on the St Lukes overbridge in both directions
- Improved walking and cycling facilities across the bridge – you’ll be able to use both sides of the widened bridge
- Realignment the Northwestern Cycleway
Being able to use both sides of the bridge will be good but that seems to be the only thing.
Here’s what it will look like from above and facing south (click to enlarge)
Immediately there are a couple of major issues I see and they primarily relate to the intersection with Gt North Rd. Amazingly the NZTA and Auckland Transport are actually going to remove some of the few bits of existing pedestrian priority that currently exist. A person wanting to get from the eastern side of St Lukes Rd (where the carpark is) to MOTAT or Western Springs first has to battle their way across to the traffic island if they can find a gap in traffic thanks to the removal of the existing zebra crossing. Then instead of a simple trip across to the northern side of Gt North Rd they have to cross to the eastern side of St Lukes Rd and wait again to get across Gt North Rd.
It’s pretty clear that the primary focus of this project is about making it easier to drive at the expense of other modes. The extra lanes on the bridge are an attempt to squeeze a few more cars through the area. On westbound off-ramp there is also an additional queuing lane which will only serve to funnel extra volumes off the motorways and onto the local streets. It seems to be the typical ‘give every type of movement its own lane’ type approach that only ends up making life easier for cars. By in large everything seems very much the same business as usual crap we’ve seen for decades throughout Auckland.
Most proposals to build new roads or widen existing ones seem to boil down to an ultimate belief that it will “help the economy”. Whether it’s by improving freight reliability or getting people to their jobs faster or helping business travel or whatever, there seems to be a fundamental belief among many that quite a strong relationship must exist between building more roads and improving the economy.
Clearly this is a contestable assumption, and some recent research in the USA details some pretty interesting trends – as reported on in Planetizen:
University of Minnesota professor David Levinson has written in the past that, because of the relative completeness of our national highway network and the cost of construction, the return on investment for additional mileage is approaching zero. One study estimates the return on investment for highway construction was just 14% between 1990 and 2000.
I recently decided to follow up on this line of research, so I dug through some Census data. What I found was shocking, though not altogether surprising. It seems that, besides wasting billions of taxpayer dollars, road-building may actually be holding back economic growth overall: from roughly 2000 to 2010, states that built the fewest urban road miles grew an average of 64 to 94 percent faster than their asphalt-enamored neighbors. Rather than increasing productivity through increased mobility and reduced congestion, as politicians and lobbyists so often promise, all this mindless road-building could be depressing statewide economic growth!
Let’s look at the details a bit more:
Looking at the numbers in aggregate, we see some interesting trends that seem to hold up just about any way you slice the pie:
- States that increased their urban road mileage by less than 30% grew by an average of 14.40%, while those that increased mileage by greater than 30% grew by an average of just 8.77%.
- If we set the cutoff at 20% mileage growth, states that built less grew by 17.97%, and states that built more grew by 9.24%.
- At a 10% cutoff, states that built less grew by an impressive 20.70%, compared to just 10.66% for those that built more.
Statistically, analyzing the correlation between road-building and economic growth gives us an r-score (correlation coefficient) of -0.34, which implies that about 10% of a given state’s economic growth can be explained by how much urban road-building they did over this time period. Many things influence the overall health of any economy, obviously, so we shouldn’t expect the quantity of roads to wholly predict statewide economic growth by itself, but this does indicate a negative correlation between the two variables: more roads equals less growth. (As always, please remember that correlation does not imply causation.)
And for a graphed comparison:
The post’s author, Shane Phillips, doesn’t think that these results are particularly surprising:
None of this should be particularly surprising. While politicians and advocates love to tout the job-creating value of new road and highway capacity, congestion reduction rarely lasts more than five years and widened roads ultimately only succeed in extending the boundaries of wasteful, unproductive sprawl. In the case of road widenings, it’s entirely possible that the disruption caused during the construction phase completely erases — or even exceeds — the fleeting benefits of reduced congestion.
Then there’s the opportunity cost: think of all the good that could have been done with the hundreds of billions of dollars spent on roadways over that period: more responsible transportation spending, education, renewable energy … take your pick.
I think it’s probably unlikely that building roads directly harms the economy, but there are logical reasons to think that it might cause indirect harm: particularly due to it not the best use of public funds and encouraging dispersed land-use patterns which undermine agglomeration. New Zealand’s heavy dependency on private vehicles also forces us to spend a lot of money each year importing cars and oil – basically cancelling out wealth that we create from exporting dairy to the the world.
The next version of the Government Policy Statement will be released some time later this year. If it’s anything like the current version it will stress the importance of transport’s role in improving the economy and then make a giant leap of faith in assuming that building more roads is the best way for transport to improve the economy. It’s time to fundamentally question that assumption.