What is a catchment in Placemaker?

A catchment is a defined geographic area that represents a service area: the zone a facility, service or location draws its population from. In Placemaker, you create a catchment to get population and dwelling forecast data for the specific area that matters to your planning decision.

Key Concepts

Service area

A service area, or catchment, is the area a facility realistically serves. A school's catchment is the area students are likely to attend from; a hospital's catchment is the area patients are likely to travel from.

How catchments work in Placemaker

Catchments are built from SA1 statistical areas, the smallest standard ABS geography. When you set a boundary by radius or drive time, Placemaker includes the SA1 areas that fall within or touch that boundary, then aggregates forecast data across them to produce catchment-level insights. See What are standard ABS geographies?.

Why catchments matter for planning

A catchment moves you from broad analysis to a specific service area. Instead of suburb or LGA data, you get forecasts for the exact area your facility will serve.

How This Applies in Placemaker

You create a catchment by setting a location, then choosing a method:

Radius: a circular area at a set distance from the location.
Drive time: the area reachable by road within a set number of minutes.
Clicking areas: select SA1 areas on the map to build the boundary by hand.

Once you've previewed a radius or drive time boundary, you can refine it by clicking SA1 areas to add or remove them. After saving, you can open the catchment's insights (population composition, growth trajectory and dwelling forecasts) and export charts and data for that area.

Frequently Asked Questions

Q: Why is my catchment made up of small areas rather than a neat circle?

A: Placemaker builds catchments from whole SA1 areas that fall within or touch your boundary, so the forecast data can be aggregated accurately. The edge follows SA1 boundaries, so it can look slightly irregular.

Q: Should I use drive time or radius?

A: Use drive time when travel to your facility matters, for example a school or clinic. Use radius when you want a simple, consistent distance from a point.

Q: Can I change which areas are in my catchment?

A: Yes. Click SA1 areas on the map to add or remove them before saving, or edit the catchment later. See How to edit a catchment in Placemaker.

Q: How large can a catchment be?

A: You can set a drive time up to 60 minutes or a radius up to 50 km. Larger areas take in more SA1 areas, which can slow the catchment down.