Willoughby flood map & planning overlays
A planning-constraint profile of Willoughby
(Kangaroo Island Council, SA) - 26.08 km², mapped from live council and
state overlay data. This suburb is highly constrained.
Profile updated 8 September 2026.
Suburb-wide figures; the free map shows which overlays touch your lot.
Constraint readout
26.08 km² - this suburb is highly constrained by planning overlays.
Elevation hillshade with street names, clipped to Willoughby's boundary, with the flood, bushfire and environmental overlays drawn on top.
Nearby suburbs, nearest first
Aircraft noise and flight paths over Willoughby
Two different things, kept apart on purpose. The ANEF contour is the planning instrument - a forecast published per airport that planning schemes use to control noise-sensitive development. Observed overflight is what a sampled aircraft-tracking feed actually recorded over the suburb - where aircraft flew, how low and how often.
Observed overflight - sampled to
Night movements: not established - night is sampled as often as day, but too few night flights have been seen here to conclude either way.
Traffic is sampled rather than watched continuously, so every figure is a floor: aircraft not captured between samples are not represented. Rates are per 500 m square - the busiest square in the suburb, not a count of flights over the suburb - and a square is only rated where enough traffic was seen to measure it. Altitudes are above mean sea level. Flight paths change with runway use, weather, season and airspace design. This is a record of observed traffic; it is not a noise contour and not a planning control.
Willoughby at a glance
How Willoughby is zoned
Selling in Willoughby? The zone and overlays on this page are the Planning and Design Code controls a Form 1 vendor's statement has to disclose.
Across its 26.08 km², Willoughby is highly constrained by planning overlays. Flood mapping covers the suburb and none of it falls within a mapped flood overlay, and 99% is flagged bushfire-prone. There are 2 heritage-listed sites on record, and the dominant land-use zone is Rural. The median lot measures about 220,299 m² across 48 parcels.
Who lives in Willoughby
Census 2021 figures published by the ABS for the Willoughby suburb boundary itself, not a wider region.
Socio-economic standing
ABS SEIFA 2021 ranks every Australian suburb. Decile 1 is the most disadvantaged tenth of the country, decile 10 the least.
Score 975, and decile 5 within South Australia. The national average is 1000.
Population trend, 2001 to 2025
Estimated resident population of Kangaroo Island, the wider ABS statistical area containing Willoughby. There is no annual population series published at suburb level, so this describes the surrounding area rather than Willoughby itself.
4,227 in 2001 to 5,212 in 2025, up 23%.
Source: ABS Census 2021 and SEIFA 2021 (Suburbs and Localities), Regional Population (SA2), CC BY 4.0. Small counts are randomly adjusted by the ABS.
Willoughby data sources and coverage
“Not mapped” means we hold no source layer for this suburb - never an all-clear.
| Dataset | Coverage | Publisher |
|---|---|---|
| Flood mapping | Mapped | the South Australian Planning and Design Code and Location SA spatial data |
| Bushfire-prone mapping | Mapped | the South Australian Planning and Design Code and Location SA spatial data |
| Zoning | Mapped | the South Australian Planning and Design Code and Location SA spatial data |
| Heritage and environment | Mapped where published | the South Australian Planning and Design Code and Location SA spatial data |
| Aircraft noise contours (ANEF) | Not held | the South Australian Planning and Design Code and Location SA spatial data, Defence |
| Observed flight paths | Observed | adsb.lol, under the Open Database License |
| Demographics | Available | Australian Bureau of Statistics (2021 Census and SEIFA) |
Profile last materially updated 8 September 2026. See the methodology and full source list. Source data changes over time and critical decisions should be checked with the responsible authority.
Check a specific Willoughby address
See exactly which overlays touch a single property - the interactive map is free. Need it on paper? A full planning PDF is just $9.
Building or pricing a slab? The $119 geotechnical desktop report covers geology, soils, bores and an indicative AS 2870 site class for a Willoughby lot.
See what's in the $9 report →Willoughby planning - frequently asked
Is Willoughby flood-prone?
Flood mapping covers Willoughby and less than 1% of the suburb falls within a mapped flood overlay (the council-wide suburb average is 7%).
Is Willoughby bushfire-prone?
Around 99% of Willoughby is mapped as bushfire-prone, compared with a Kangaroo Island Council average of 96%.
Is Willoughby under a flight path?
No aircraft were observed over Willoughby in the period sampled (recent weeks to now). Sampling is intermittent, so that is a floor rather than proof that none fly over. Traffic is sampled rather than watched continuously and flight paths change with runway use, weather and season; the ANEF contour is the planning instrument.
What is the zoning in Willoughby?
The dominant planning zone in Willoughby is Rural, though the suburb also includes Conservation and Coastal Waters and Offshore Islands.
Does Willoughby have heritage-listed places?
Willoughby has 2 heritage-listed places on record.
What is the typical lot size in Willoughby?
Across 48 surveyed parcels in Willoughby, the median lot size is about 220,299 m².
Is Willoughby an advantaged suburb?
On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Willoughby scores 975 and sits in decile 5 of 10 nationally and decile 5 within South Australia (decile 1 is the most disadvantaged tenth, decile 10 the least).
Compare nearby suburbs
| Nearby suburb | Distance | Flood mapped | Bushfire-prone |
|---|---|---|---|
| Antechamber Bay | 6.6 km | 17% | 99% |
| Porky Flat | 7.3 km | 0% | 100% |
| Cuttlefish Bay | 11.1 km | <1% | 100% |
| Dudley East | 13.1 km | 0% | 100% |
| Willson River | 14.8 km | 0% | 99% |
| Ironstone | 15.1 km | <1% | 100% |
| Penneshaw | 18.5 km | 3% | 98% |
| Kangaroo Head | 20.8 km | 2% | 99% |
| American Beach | 21.2 km | 14% | 93% |
| Dudley West | 21.2 km | 0% | 100% |