How many motorways does a big city need? And what sort of city do we want?

On Friday, The Age reported that Infrastructure Australia has put out a report that asks what sort of city we’d like to have in 2046:

  • The Expanded Low Density scenario – similar to Los Angeles – sprawling, dispersed suburbs, even more car-dominated than today
  • The Centralised High Density scenario – similar to New York City – concentrating jobs and housing in the inner 15km ring
  • The Rebalanced Medium Density scenario – similar to London – medium-density over a wider area, and jobs closer to where people live

IA’s question is a good one, and put in terms many people can understand.

If the populations of Melbourne and Sydney continue to grow, we will end up being more like the population of LA, NY or London.

What outcome do we want? Because that’s the one we should plan for.

Sunday afternoon traffic on M1 exit to Kingsway

As it happens, also on Friday, the Financial Review reported that the International Monetary Fund says Australia has been spending too much on roads, and the pendulum needs to swing to railways, ports and airports.

All this raises many questions, but here’s one I’d already been looking into:

Do more populous cities have more motorways?

How many motorways are there in LA, NY and London, and other big cities, compared to Melbourne?

I looked at the total kilometre length of motorways in the three cities – plus a few others where I could easily find data.

Motorway kms by city

Some caveats:

  • I went looking for numbers, and in some cases got lists of motorways (freeways and tollways) from Wikipedia and added their lengths together, or found an official source (LA, NY)… a more exhaustive study would probably have better sources than this.
  • You could argue that motorway lane kilometres are more important than just length, as the number of lanes can radically alter carrying capacity.
  • You can also argue that other types of roads, such as major arterials, can play a big part in overall road space and capacity in a city, but let’s keep it simple and focus on motorways.

…taking that into account, you will note that Melbourne already has more motorways by length than London and Sydney.

In fact we’ve already got more kilometres of freeways than any other city in Australia, but the WestGate Tunnel and North East Link, which the current government wants to build, will see go even further beyond the others.

Houston is the clear king, at least in this small sample. That’s the city where they keep massively expanding their freeways, but their traffic doesn’t get any better.

Westgate Freeway, Sunday morning

What do the big cities do?

Motorway length is obviously dependent on city size.

Some people argue that as our cities grow in population, they need more motorways.

What happens when we divide by population (for the same area) to find the motorway kilometres per million people?

Motorway kms by city and population

Obviously a more exhaustive study, with more cities, using this type of methodology would be interesting.

Nonetheless… by this measure, what’s striking is that we in Melbourne have more motorways per person than London or New York City. If we keep building them, we’ll creep closer to Los Angeles.

Back to the IA question: what do we want for our city? LA, NY, or LDN?

I don’t think we want to be like LA. Sprawling, dispersed suburbs dominated by cars? LA’s bad traffic is notorious. No thanks.

New York or London? I’d personally prefer London. Gentler medium density, and spreading employment centres over a wider area.

The key thing to remember is which transport modes move people efficiently as cities get bigger. As I said recently: Roads get less efficient the more people use them … Public transport gets more efficient.

And we will get the city that we plan for and build for.

On the measure of motorways at least, if we want to be like London or New York, there’s a lot to do to achieve that… but building more motorways isn’t one of them. Time to look for more efficient ways to move people around.

Update 26/2/2018 9:45pm. Found an error in the Brisbane data. Corrected.
Update 27/2/2018 7:00pm. Sydney data also corrected. Thanks for the feedback.

PS. Tony Morton said it well:

The “tradies” argument for more roads

The argument for more/bigger roads (particularly motorways) is often that tradies and others need to carry their tools and equipment to jobs, so they can’t use public transport.

Perhaps that’s true, but they are the minority of people on the road.

According to a 2012 ABS study, only about 7% of people avoid using public transport (for work or study) because they need to carry tools etc. Another 10% say they have to take their own vehicle.

The more significant reasons are that no public transport is provided (about 30%), they want convenience/comfort/privacy (28%), the services aren’t convenient (25%), or the travel time is too long (18%).

So for the vast majority of people on the roads, it’s because the public transport service isn’t good enough, not because they inherently can’t use public transport for those trips. There might be some overlap in responses of course, but I suspect most people travel most of the time with nothing they can’t carry themselves.

And in fact if you jump on public transport at the right time, such as early morning and early afternoon, you’ll see plenty of blue collar workers using it — presumably those who don’t use personal tools, or are able to keep them securely on-site.

Swan St traffic

Of course, if building new motorways were really to prioritise those vehicles that have to use them — trucks carrying freight, tool-carrying tradies and so on — there’d be priority lanes to make sure those vehicles got through without getting caught up in congestion caused by individuals in cars. But no roads have such priority lanes.

Source: ABS

Related: Average car occupancy figures – about 1.2, and dropping

Edit 29/4/2017: Added top image of a tradie and his tools on a train to Pakenham.

Some reasons why the east-west road Eddingtunnel makes no sense

Some reasons why the Rod Eddington-proposed east-west road tunnel makes no sense:

1. Eddington’s own study showed the road tunnel would have a benefit/cost ratio of just 45 cents in the dollar.

2. Even including the rather wobbly “wider economic benefits” only got it up to 72 cents. (Only by lumping in other projects including the rail tunnel with the road tunnel were they able to get a result that was anywhere near economically viable.)

In short, anybody with any hint of economic rationalism in them should reject the road tunnel as unviable.

Alexandra Parade, eastbound on a Saturday

3. People seem to think it’s just a problem with cars coming from the big road (Eastern Freeway) onto the little one (Elliot Avenue/Macarthur Rd, through Parkville), as if all the cars are headed from freeway to freeway. They’re not of course.

The photo above shows Alexandra Parade eastbound on a Saturday. Those three clogged lanes of traffic didn’t come from the one lane through Parkville. Eddington’s tunnel wouldn’t fix this, because under his plan, it wouldn’t have interchanges anywhere near there:

there are sound operational, functional and strategic reasons for this section to act as a northern city bypass, and city access ramps have not been included.Chapter 9

And if it was modified so it did have interchanges, it would devastate large areas of Melbourne’s prime inner-northern suburbs, due to the massive amounts of land required.

4. And the westbound traffic? The Northern Central City Corridor Study showed that most traffic from the Eastern Freeway is heading to the city and inner suburbs, only about 10% heads across town to the Tullamarine Freeway/Citylink or further west. (See below)

Upgrading circumferential public transport (including, but certainly not limited to implementing the scrapped Blue Orbital Smartbus, and higher-frequency services right across Melbourne to make more non-CBD point-to-point trips easier by PT) would help cater for cross-city travel more efficiently.

Where traffic from the Eastern Freeway goes

5. You don’t fix traffic by building road capacity. It doesn’t work. It never works, due to induced traffic: once increased road capacity makes it easier to drive, people do so, by making more trips or moving trips from other modes.

The net result? Billions spent creating more traffic.

6. The claims of a “backup to the Westgate bridge” don’t stand up. Footscray Road, Dynon Road and Smithfield Road together provide six lanes each way across the Maribyrnong River (one more lane each way than the Westgate). They don’t work as a backup because they have their own traffic to deal with. It would be the same with a new tunnel.

It could only ever work as a “backup” if it is kept closed and unused until the Westgate is blocked. Which is not the way multi-billion-dollar pieces of infrastructure are generally used.

7. One reason Eddington’s study wanted more roads was that it assumed public transport use would not grow strongly:

In 2031, the daily number of public transport passenger trips is predicted to be around 1.4 million

In reality, it reached that level in 2010. The last thing you’d want to do is undermine that by mass building of new road capacity that would encourage people back into cars.

The benefits of WestLink

Letter in The Age today from Tim Pallas, Roads and Ports Minister:

I AM happy to assure people (Letters, 5/12) that 1000 homes will certainly not be acquired for the WestLink project.

The Government recently announced a $10 million study to work with the community to develop the best location for the tunnel and road. We’ll be doing a lot of work to ensure we minimise the impact on residential properties – even at this early stage we know the figure will be significantly less than 1000, and less than even half that number.

So it rather sounds like around 400-500 homes will be sacrificed to the road-building gods, should the government push ahead with WestLink.

Taking traffic off local roads and on to freeways will help ensure that areas such as Footscray and Seddon are safer, cleaner and more attractive places to live.

This was the experience with the CityLink and EastLink tunnels and we see no reason why the west should not be entitled to the same benefit from such valuable projects.

Ah yes. Thank goodness the construction of Citylink in the 90s means King Street never gets congested anymore. And as you can see, having rid itself of all that traffic, that area of the city is so attractive.

King Street, lunchtime