Yesterday saw the release of the first batch of data from the 2011 Australian Census and my inner statistics nerd was very excited. But the census is not just for demographers and statistics nerds – it has real practical uses for emergency managers. Here’s just a few areas where it comes in handy:
Risk is often characterised as Hazard X Vulnerability. Hazard is generally easy to determine and there are substantial studies on natural hazards in particular. Vulnerability can be much more difficult to determine, especially when talking about people. What makes someone vulnerable will ultimately depend on a host of complicated factors and relationships, but demographic data can provide some coarse indicators.
A description of a community and its vulnerabilities is grounded in solid demographic data, the best of which comes from the census. It can suggest specific issues in a community and allow researchers to target further work to better reveal and understand its vulnerabilities.
The census reveals a raft of data about socioeconomic status, education, age, family characteristics, motor vehicle ownership, English language ability and employment. It can help identify communities where there are concentrations of people who may be more vulnerable in the event of a disaster and thus at higher risk. This can inform risk assessments and ultimately target mitigation and preparedness measures at these communities.
Modern evacuation management depends on demographic data to ensure that the population of an area can be evacuated safely in the event of an emergency. It is particularly relevant for emergencies where there is some warning such as floods, tropical cyclones and bush fires. Here are some key items useful in evacuation planning which can be derived from census data:
Total Population: This number isn’t as important as you might think, but it’s a good starting point. Evacuation centres need to be able to cope with evacuees who go there, but most people who evacuate prefer to stay with friends and family. Still the total population can give an indication of the number of people evacuation centres may need to assist.
Number of households: Although technologically based systems, such as Emergency Alert in Australia, are being increasingly utilised by the emergency services doorknocking remains a mainstay of evacuation warning. It is an effective means of warning, particularly when combined with other methods such as mass media and new technology. Doorknocking is resource intensive in terms of personnel and time. To know how many teams you need or how long it will take you need to know the number of doors that need to be knocked. The census provides answer in the number of households in an area.
Number of cars: In Australia and most other developed nations motor vehicles are the traditional method of evacuation. Australian emergency managers pioneered simple methods for calculating the time required to evacuate an area along a limited number of routes. The number of motor vehicles is a key factor in this calculation. Most households will take all their cars with them, so you can’t just rely on household numbers. With the rise in number of motor vehicles per household, knowledge of the number and growth over time in an area is critical to ensuring safe evacuation.
Number of households without cars: This is a critical factor to ensure that sufficient alternative transport is provided to evacuate those without a vehicle.
Number of vulnerable people: Those who are elderly, have a disability or are from a Non-English Speaking background may find it difficult to either evacuate on their own, or understand the evacuation warnings. These people are present in all areas, but if the census identifies a particular concentration this can allow for emergency planners to take their needs into account and plan accordingly.
Census data can also show changes in population in an area over time indicating when evacuation routes may reach capacity. This should trigger the need to either curb development or increase the capacity of these routes.
Community engagement material and programs will function best if they are targeted and tailored to the at risk communities. Some of the useful census data for community engagement includes:
Language: A common and relatively cheap option is to reprint preparedness materials in different languages and then distribute these materials among the communities who speak that language.
Non-Private Dwellings: The census doesn’t just count people at home. It counts people in hospitals, prisons and other institutions. This can help emergency managers identify areas with a large concentration of facilities like nursing homes and hotels, which need to be targeted with education materials specific to their circumstances.
Private Dwelling types: The types of private dwellings in an area and the number of people in them can also suggest how community engagement should be targeted. For example caravans are a high risk group combining both high hazard (caravan parks are often in hazard prone areas) and high vulnerability (long term residents of caravan parks often have low socioeconomic status and may also be elderly or have a disability). Census data can identify at a broad scale areas with large concentrations of caravan residents enabling emergency managers to locate the individual parks and target education efforts.
New features in the 2011 census
There have been some changes to the way the census data is packaged for use. Of particular relevance to emergency managers are changes to the geographical areas on which census data is reported have improved in granularity. This allows emergency managers to examine demographic data on much smaller areas. Over time this will enable approaches that are increasingly customised towards communities.