Sydney, Where Art Thou?

A while back, I read an article ...
http://smh.domain.com.au/real-estate-news/one-in-five-sydney-suburbs-now-has-a-sevenfigure-median-house-price-20131019-2vtlt.html

For those living outside of Sydney, this seems sensationalist, but it is probably "true" in some sense, until you start to think deeply about how the one-in-five number came up. It quotes that 123 suburbs now have that median price, meaning that it is no longer an indicator of prestige.

There are a few questions that come out of this - does Sydney have around 600 suburbs? Who defines Sydney? Are other cities measured in the same way when they say that Melbourne has 26 such premium suburbs? Actually, what defines a suburb?

The City of Sydney is a tiny thing where business people by day rub shoulders with trendy inner-city dwellers by nigh. It contains a handful of suburbs. It has a Lord Mayor(ess). It has no actual control over anything outside of that area - so where is Sydney?

I remember when I was growing up that Brisbane was considered bigger in area than Sydney because it was defined as reaching out to Ipswich. Most people wouldn't have known that. But then, most people, if asked, couldn't name ten percent of Sydney's suburbs, let alone indicate how big it is. If you'd asked me before I started this journey, I would have waved my hands about & said that it's more or less encompassed by the George's River & the Hawkesbury-Nepean River. Simple. Wrong. Google gets close with its dotted outline when you ask for a map of Sydney - but they're missing two (large) areas.

Another nice definition would be Cumberland County. Strangely, this is too big (much bigger than I expected) - it encompasses bits of Wollongong.
http://en.wikipedia.org/wiki/Cumberland_County,_New_South_Wales

It would appear that, since 2012, at least, the Sydney Metropolitan area is defined as a collection of LGAs (Local Government Area = Council = Shire/Municipality) - 40 of them. Most of these are cities in themselves (population over 100000).
http://www.austlii.edu.au/au/legis/nsw/consol_reg/rdr2012305/s4.html
This is one of very few places where you will see an outright definition, as "everyone knows" what is meant by Sydney.


But I now had a task - to find & count the suburbs of Sydney - the Sydney Metropolitan Area.

I've seen people try to define Sydney as a series of postcodes. I'm not sure how you can do that nicely, but it probably made sense once (postcodes were introduced in 1967). AusPost is a very good place to start for a list of "places" which are suburbs, or else suburb-like places. When I used to work in data quality, these latter were known as "vanity addresses" - quite a valid way to indicate where you live, but essentially hiding the fact that your neighbours have a bad reputation. Try working out where Round Corner's boundaries are, for example, because it doesn't exist.

Before they changed the telephone numbers, Telstra had a definition of Sydney for the purposes of charging people for non-local phone calls. Unfortunately, since telephone numbers were first issued, there have been some changes to the definition of Sydney & its LGAs, & changes to the numbering scheme since 1994. Thus, Campbelltown City (once outside Telstra's Sydney) now includes areas that used to be in Ingleburn Council, which was inside Sydney (after a council merger in 1948).

So, to find Sydney, it should be just a matter of looking over the 40 LGAs & listing out their suburbs ... not that easy. Each LGA will make proposals to the Geographical Names Board (GNB), which go through an approval process with requirements like having a distinct sense of community in that proposed area & independent facilities (post office, community hall, ...). This process takes time, but the council's proposal is quite public, so people can make assumptions about suburbs "about to happen". You only expect a suburb a year to pop out of this process. The state government can create whole communities with housing developments (out of nothing) every so often.

But how do you find the definitive lists of councils & suburbs? It is within the purview of the Division of Local Government (DLG) to co-ordinate LGAs. They divide councils across the state into regional groups - inner Sydney, outer Sydney, & Sydney surrounds, for example - but these are outdated groups, as half of the last group are in the metro area. The DLG get their council/suburb breakdown from the Division of Land & Property Information (DLPI), but that info is out of date. Some older suburbs stretch over two or more councils thanks to various redistributions (under the control of the state government), so there's no direct correlation to LGAs. Fortunately, within Sydney, there have been no doughnut councils created or re-amalgamated.

After working through an exhaustive process, I found 746 suburbs in Metropolitan Sydney. So, unfortunately, the original article was wrong - it's more like one in six. Does that make me feel better? Superior to the journalist? Happy that I don't live in one of those suburbs? Happy that I live in Sydney regardless?

No. It just gives me a warm feeling that I think I know where Sydney is. It also makes me a little sad that I may be the only one.

Postscript - I'm updating my estimate to 854!