The SSD is a general purpose spatial unit of intermediate size between the SLA (smaller) and the SD (larger) in the Main Structure.
In this edition of the ASGC, there are 207 SSDs in Australia.
Delimitation of SSDs
The delimitation criteria for SSDs are as follows:
- SSDs consist of one or more SLAs. In aggregate, they cover Australia (as defined in Chapter 1) without gaps or overlaps. The larger spatial units of SDs and S Dists can be formed by aggregation of SSDs (see diagram 3, Chapter 1). SSDs do not cross S/T boundaries except in the case of the Other Territories SSD, which comprises the three Territories of Jervis Bay, Christmas Island and Cocos (Keeling) Islands.
- SSDs are defined as socially and economically homogeneous regions characterised by identifiable links between the inhabitants. Moreover, in the non-urban areas (i.e. outside the capital cities or areas with population clusters of 25,000 or more people), an SSD is characterised by identifiable links between the economic units within the region, under the unifying influence of one or more major towns or cities.
- Where possible, SSD boundaries embrace contiguous whole LGAs. However, in some cases e.g. where S Dists or capital city SDs have been defined, an SSD boundary may split the LGA into parts with each part of the LGA forming part of the relevant SSD (e.g. the SSDs of Gold Coast City Part A and Gold Coast City Part B dissect the LGA of Gold Coast City in Queensland).
the Ballarat City SSD in Victoria covers the same area as the Ballarat S Dist.
- One or more SSDs must be defined for an S Dist that falls within an S/T.
the Albury SSD in New South Wales plus the Wodonga SSD in Victoria together cover the same area as the Albury-Wodonga S Dist which lies partly in New South Wales and partly in Victoria.
- One or more SSDs must be defined for each part of an S Dist which straddles an S/T boundary.
in New South Wales, the SSD of Hunter SD Bal is defined as the part of the Hunter SD which is outside the Newcastle S Dist (and Newcastle SSD).
- Where an SD contains an S Dist (or part of an S Dist), one or more SSDs must be defined for the S Dist and at least one SSD for the remainder of the SD which falls outside the S Dist even though the SSD(s) so defined may not have a predominant town or cluster of towns with a unifying socioeconomic influence over the region.
The coding conventions for SSDs are as follows:
- One Off-Shore Areas & Migratory SSD is defined for each S/T except the Australian Capital Territory and Other Territories.
Albury 15505 (in New South Wales)
Wodonga 24505 (in Victoria)
- SSDs are identified by unique two-digit codes within SDs. Unique Australia-wide identification of SSDs is obtained by use of a five-digit code comprising S/T code (digit 1), SD code (digits 2-3) and SSD code (digits 4-5).
- SSD code 88 has been reserved for special purposes (see Chapter 9).
- In the Main Structure, SSD codes are arranged in ascending numerical order within an SD. Gaps have been provided between the codes for future expansion or change.