Tuesday, March 19, 2013

Dense and Denser

The Auckland Unitary plan was released and our little stem-cell of a community up in Riverhead is concerned that we will be swallowed by urban sprawl thanks to the redefining of the Rural Urban Boundary (RUB).

This post isn't really about that, but it's what sparked my investigation (as well as reading this article a while ago and deciding to delve into the figures myself). I hear people mention Auckland's spread out population and unnecessary urban sprawl all the time. "Auckland is the size of London with one tenth the population", they say. As well as, "Auckland is too spread out, that's why public transport doesn't work". Then there's the age old adage that I've heard since cows outnumbered Albany residents, "in terms of land area, Auckland is the second largest city, behind Los Angeles".

I'm not sure where the latter came from. In fact, it's actually very hard to find metropolitan area statistics, as these are defined differently in each country and mean different things. According to Wikipedia, "the parameters of metropolitan areas, in both official and unofficial usage, are not consistent"; so a comparison is flawed from the beginning. However, like a good scientist I'll proceed anyway. Using the numbers I could get hold of, I found that the Los Angeles Metropolitan Area encompasses LA and Orange county and covers 12,520 km2, while the Greater Auckland Region (a similar geographical type of area) only covers 4,894 km2. I guess that doesn't really say much, because it's only two metropolitan areas. So, I found a couple more metropolitan areas for comparison. The Tokyo Metropolitan Area is 13,400 km2. That rules out LA as being the largest. The Sydney Metropolitan Area covers 12,145 km2. Not as big as LA, but still bigger than Auckland. It's still hard to find any data on the whole 'volcanic pancake' theory, but it's not looking promising.

I'm here to write about things that matter to people though, like housing density and public transport. For that we have to concern ourselves with the urban area. This is the more populated part of a city. In Auckland, of the 1.5 million people that live in the greater metropolitan area, approximately 1.4 million live within the urban area. Demographia defines an urban area as, "the lighted area that can be observed from an airplane (or satellite) on a clear night". When you look at a city on Google Maps, it's reasonably obvious what would be called the urban area. It's the large grey mass nestled amongst green fields.  Here's a very rough diagram I made showing the Auckland urban area overlayed on London, Sydney and Los Angeles.

You can see that Auckland (the one that looks like a depressed seahorse) is considerably smaller than the other cities. It's one third the size of London, so there's another comparison that's inaccurate. Overall, the Auckland urban area ranks 229th in urban area size; equal with Kiev, Nanchang, Warsaw and Huntsville, Alabama.  "But the population is much smaller", you say. This is true, however next we look at population density within those urban areas; those statistics are much easier to come by and tell a different story.

Ignoring the developing world and their over-crowded cities (not altogether or course, just for the purpose of this post), here is a table of Auckland's population density compared with other major cities (hand selected by me for maximum dramatic effect).

According to this, Auckland is on par with Los Angeles, a little less dense than Amsterdam and denser than Sydney. Denser than Sydney? But their public transport is amazing?! That's right, so there goes another argument. Our public transport sucks just because it does, not through any fault of the city's layout. Since we're always trying to live up to our big brother, let's look a little closer at Australasia.

Auckland is actually the most densely populated city in Australasia. Even Hamilton and Christchurch are more densely populated than Sydney (although I'm sure these figures are pre-earthquake) and Wellington is equally dense. This is just the urban area, remember, not all the rural parts and satellite towns. But even in regards to this part of Auckland, people complain about public transport and the fact that we're building "out not up". I won't go into the fact that when the council dares to suggest people build up, there is opposition to that as well.

The fact is, Auckland isn't as sprawling as people seem to think. It's urban area is considerably smaller than most other major cities and it's population density is higher than many. Does that mean I want Auckland to keep expanding and Riverhead to be swallowed up? Of course not. But it will. I just hope that the low density excuse gets phased out and we can focus on improving infrastructure like public transport alongside the expansion. Most important of all, I hope people consider the actual population density of Auckland when complaining about urban sprawl instead of assuming we're more spread out than LA just because they can see a tree from their bedroom window.

PS: I spent a while putting together a full spreadsheet of all the urban land areas and populations in the world (taken from Demographia.com), so if you want it you can download it here.


  1. Neato; I've been hearing the low-density-sprawl talk for the better part of a couple decades now, but without anyone offering any actual sources or data - good to see what reality stacks up to :)

  2. This is God's work Gareth. I love it.
    It's crazy that we have a denser population than Sydney, but people still think big villas on 400sqm+ sites, located practically at the foot of the Sky Tower, are their God-given right.

  3. Very interesting stuff. Tell me - where is Titirangi village relative to the urban boundary? Always thought the crap public transport was because of the density, but thinking about it now, I guess both density and overall population are important. Economies of scale may mean that a train network serving a population of 4m in Sydney is more efficient than a train network serving 1.5m in Auckland even if the network in Sydney is larger in area? Or perhaps more relevant is the population density of people that actually use public transport?

    1. Titirangi is on the very edge of the urban area. I don't think economy of scale would apply. If population density is higher, then in theory each bus/train station would be serviced by more people, regardless of total population. I think people using it is the bigger issue. But then people don't use it because it's crap, and the council won't invest in upgrading it unless people use it. We just didn't do it well early on like Sydney did, so we're kind of screwed (our topography makes it a bit harder too).

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  5. Don't confuse Los Angeles City with the Los Angeles "metro area". When people visit "Los Angeles", they probably never set foot in the actual City. Instead they go to West Hollywood, Santa Monica and Malibu.

    Also the metro area is largely undefined. If you blink you can easily stretch it to San Diego...the rows of houses simply do not stop from Los Angeles to San Diego.

    You don't want Los Angeles City. Some of the "metro areas" can be nice...but they are very dense (Santa Monica, West Hollywood and Universal).

  6. Ah, but what's the distribution of the density - that'll be an important point. If we had a comparitive map of areas of density of 4 or 5,000 and greater what would that look like?

    It may be what's important for PT and other city provisions that you need some dense sectors, rather than a whole city denser. All cities (other than HK / Singapore) are going to be somewhat diluted by the semi-rural fringe, let-alone the sparse normally-housed suburbs...
    It's the other side to the fear we'll all be forced to live in boxes - increasing density is more about 3 or 4 storey townhouses along major PT routes than making us all live in boxes. Still plenty of the detached housing suburbs available...

    Anyway, great to have some more data - I never thought the "2nd biggest after LA" story could be right...

    And looking at our north-south on the urban area map our topography does look like it'll cause some spanners in the works (if not as much as HK & Singapore...).

    (Are cities bigger if they're more inefficient about light use? Do they shrink at Earth Hour ;) )