Most of our journeys begin with maps. We turn to maps to find out where we are and where we are going. Maps are also used to mark out areas of responsibility.
In the vast operation that is the Census of Population and Housing, maps are used to carve up the whole of Australia into districts that one person can manage. These are the maps produced for the army of collectors who deliver and collect Census forms.
The Geography section of the Australian Bureau of Statistics is responsible for producing these maps for the Census, which will be held on 8 August this year. This mapping work is all part of what is called collection district (CD) design. In the ABS, CD design has nothing to do with music. Once the collection districts have been designed, each collector is given a map of their district. They must keep within its boundaries.
A strict adherence to collection districts is fundamental to the proper operation of the Census.
The main factor determining the size of each collection district is a judgement of what is reasonable for a single collector to deal with. It is based on the approximate number and types of dwellings in the district and population densities. Sizes of districts can vary greatly, particularly been city and country regions.
Factors which slow down collectors and so reduce the size of the collection district include the number of secure apartment buildings which have to be visited. It is much harder to gain access to deliver and collect forms from such apartments than it is from a row of houses open to the street. So a variety of factors have to be taken into account when drawing up collection districts.
The regional offices in each state and territory do the main hands on work in drawing up the districts, while the central office in Canberra provides coordination and support.
All the CD maps are produced in house at the Central Office in Canberra. About 100,000 maps for 38,700 collection districts have been produced. Most collectors cover more than one collection district. There will be about 26,000 collectors, with a reserve of 3,000. The 100,000 maps include two copies of each map, one for the collector and a spare for the area supervisor. The area supervisor coordinates the efforts of a number of collectors in a larger designated area. Area supervisors also have their own maps taking in all the collection districts for which they are responsible. Beyond the area supervisor is the district manager. Again they have their own maps. Then there are special copies of maps for training purposes. All this printing work was completed in December 2005.
The enormous effort involved in designing and mapping the collection districts can possibly best be described in terms of total work years. If you added together all the work time of those involved it would amount to about 35-40 years over a two-year period.
The designers work from what is called base map data. This data is provided under contract and regular updates are provided. For example when a new subdivision is planned Geography is notified through the update mechanism. Not only are new areas of population continually being added, changes take place in older areas. CD designers also gather information from local governments. Where information is harder to come by, designers go out in the field and look for themselves. They check on such things as whether an apartment building is secure or not.
Once the Census is over, Geography produces more maps, these ones are available to the public at large and based on the data collected. These maps are usually part of a publication such as the series of social atlases of the capital cities based on 2001 Census data.
Geography expects to do a similar project for the 2006 Census. The South Australian office of the ABS has responsibility for the wording and other non-map material in these atlases.
The individual maps in each 2001 capital city atlas were based on themes, such as country of birth. Each map was colour coded, making it easy to see distribution patterns at a glance. For example different colours showed the concentration of people of different places of birth in areas across a city. This was also done for such subjects as Indigenous numbers, education levels, numbers of people not fluent in English, household size and number of dependent children.