Illawong flood map & planning overlays
A planning-constraint profile of Illawong
(Sutherland Shire, NSW) - 5.93 km², mapped from live council and
state overlay data. This suburb is highly constrained.
Profile updated 3 October 2026.
Suburb-wide figures; the free map shows which overlays touch your lot.
Constraint readout
5.93 km² - this suburb is highly constrained by planning overlays.
Elevation hillshade with street names, clipped to Illawong's boundary, with the flood, bushfire and environmental overlays drawn on top. Magenta is where aircraft were observed in the sampled period, brightest below 3,000 ft.
Nearby suburbs, nearest first
Aircraft noise and flight paths over Illawong
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 4 Sep to 2 Oct 2026
typical observed square 3 a day
Night movements: observed, lowest 1,500 ft - night is sampled as often as day, but night traffic is light, so this is a floor and no rate can be put on it.
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.
Illawong at a glance
How Illawong is zoned
Buying in Illawong? The zoning, flood and bushfire lines on the section 10.7 certificate attached to the contract are mapped controls - see our s10.7 certificate guide.
Across its 5.93 km², Illawong is highly constrained by planning overlays. About 22% of the suburb sits within a mapped flood overlay, and 58% is flagged bushfire-prone. There are 26 heritage-listed sites on record, and the dominant land-use zone is Environmental Living. The median lot measures about 754 m² across 2,491 parcels.
Who lives in Illawong
Census 2021 figures published by the ABS for the Illawong 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 1108, and decile 10 within New South Wales. The national average is 1000.
Age profile
Share of Illawong's 7,427 residents in each ABS age band.
Population trend, 2001 to 2025
Estimated resident population of Illawong - Alfords Point, the wider ABS statistical area containing Illawong. There is no annual population series published at suburb level, so this describes the surrounding area rather than Illawong itself.
12,003 in 2001 to 10,621 in 2025, down 12%.
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.
Illawong 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 | NSW Government spatial services, NSW ePlanning and published council flood studies |
| Bushfire-prone mapping | Mapped | NSW Government spatial services, NSW ePlanning and published council flood studies |
| Zoning | Mapped | NSW Government spatial services, NSW ePlanning and published council flood studies |
| Heritage and environment | Mapped where published | NSW Government spatial services, NSW ePlanning and published council flood studies |
| Aircraft noise contours (ANEF) | Not held | NSW Government spatial services, NSW ePlanning and published council flood studies, 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 3 October 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 Illawong 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.
Aircraft have been seen below 3,000 ft over about 62% of Illawong. The report's Aircraft Overflight page narrows that to the address itself: how many aircraft a day, how low, and at what heights.
Building or pricing a slab? The $119 geotechnical desktop report covers geology, soils, bores and an indicative AS 2870 site class for a Illawong lot.
See what's in the $9 report →Illawong planning - frequently asked
Is Illawong flood-prone?
About 22% of Illawong falls within a mapped flood overlay, against the council-wide suburb average of 22%.
Is Illawong bushfire-prone?
Around 58% of Illawong is mapped as bushfire-prone, compared with a Sutherland Shire average of 46%.
Is Illawong under a flight path?
Aircraft were observed below 3,000 ft over about 62% of Illawong, and over about 100% at any altitude up to 10,000 ft, in the period sampled (4 Sep 2026 to 2 Oct 2026). The lowest measured aircraft was at 500 ft, with an average of 5,500 ft. At the busiest point in the suburb about 25 aircraft a day were recorded passing over one 500 m square. 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 Illawong?
The dominant planning zone in Illawong is Environmental Living, though the suburb also includes Environmental Conservation and Natural Waterways.
Does Illawong have heritage-listed places?
Illawong has 26 heritage-listed places on record.
What is the typical lot size in Illawong?
Across 2,491 surveyed parcels in Illawong, the median lot size is about 754 m². There are also 89 registered easements mapped in the suburb.
Does Illawong have a train station?
There is no train station inside Illawong itself. The suburb is served by 91 bus stops.
What is the population of Illawong?
At the 2021 Census Illawong had 7,427 usual residents, with a median age of 44 and an average household size of 3.1 people. The wider Illawong - Alfords Point statistical area, which contains Illawong, went from 12,003 people in 2001 to 10,621 in 2025, down 12%.
Is Illawong an advantaged suburb?
On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Illawong scores 1108 and sits in decile 10 of 10 nationally and decile 10 within New South Wales (decile 1 is the most disadvantaged tenth, decile 10 the least).
What is the median household income in Illawong?
Median household income in Illawong was $2,778 a week at the 2021 Census, against $2,626 for the typical suburb in Sutherland Shire. Median rent was $650 a week and the median mortgage repayment $2,976 a month.
Compare nearby suburbs
| Nearby suburb | Distance | Flood mapped | Bushfire-prone |
|---|---|---|---|
| Bonnet Bay | 1.7 km | 36% | 59% |
| Alfords Point | 1.9 km | 25% | 76% |
| Lugarno Georges River |
1.9 km | 27% | 49% |
| Como | 2.0 km | 24% | 21% |
| Bangor | 2.2 km | 10% | 73% |
| Peakhurst Heights Georges River |
2.8 km | 14% | 22% |
| Woronora | 2.9 km | 39% | 81% |
| Padstow Heights Canterbury-Bankstown |
3.2 km | 31% | 57% |
| Jannali | 3.2 km | 0% | 33% |
| Oatley Georges River |
3.3 km | 18% | 24% |