Thornlea flood map & planning overlays
A planning-constraint profile of Thornlea
(Wattle Range Council, SA) - 117.73 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
117.73 km² - this suburb is highly constrained by planning overlays.
Elevation hillshade with street names, clipped to Thornlea's boundary, with the flood, bushfire and environmental overlays drawn on top.
Nearby suburbs, nearest first
Aircraft noise and flight paths over Thornlea
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 3 Oct 2026
Night movements: observed, lowest 6,000 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.
Thornlea at a glance
How Thornlea is zoned
Selling in Thornlea? 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 117.73 km², Thornlea is highly constrained by planning overlays. Flood mapping covers the suburb and none of it falls within a mapped flood overlay, and 100% is flagged bushfire-prone. The dominant land-use zone is Rural. The median lot measures about 470,424 m² across 148 parcels.
Who lives in Thornlea
Census 2021 figures published by the ABS for the Thornlea 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 981, and decile 5 within South Australia. The national average is 1000.
Population trend, 2001 to 2025
Estimated resident population of Wattle Range, the wider ABS statistical area containing Thornlea. There is no annual population series published at suburb level, so this describes the surrounding area rather than Thornlea itself.
3,611 in 2001 to 3,676 in 2025, up 2%.
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.
Thornlea 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 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 Thornlea 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 Thornlea lot.
See what's in the $9 report →Thornlea planning - frequently asked
Is Thornlea flood-prone?
Flood mapping covers Thornlea and none of the suburb falls within a mapped flood overlay.
Is Thornlea bushfire-prone?
Around 100% of Thornlea is mapped as bushfire-prone, compared with a Wattle Range Council average of 100%.
Is Thornlea under a flight path?
No aircraft were observed over Thornlea in the period sampled (4 Sep 2026 to 3 Oct 2026). 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 Thornlea?
The dominant planning zone in Thornlea is Rural, though the suburb also includes Conservation.
Does Thornlea have heritage-listed places?
No heritage-listed places are on record within Thornlea.
What is the typical lot size in Thornlea?
Across 148 surveyed parcels in Thornlea, the median lot size is about 470,424 m².
Is Thornlea an advantaged suburb?
On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Thornlea scores 981 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 |
|---|---|---|---|
| Kangaroo Inn | 9.0 km | 0% | 100% |
| Magarey | 9.3 km | 0% | 100% |
| Clay Wells | 12.1 km | 0% | 100% |
| Hatherleigh | 12.2 km | 0% | 100% |
| Rendelsham | 12.2 km | 0% | 100% |
| Furner | 13.0 km | 0% | 100% |
| Southend | 14.3 km | 0% | 99% |
| Beachport | 17.0 km | 0% | 99% |
| Sebastopol | 20.0 km | 0% | 100% |
| Greenways District Council of Robe |
20.1 km | 0% | 100% |