Mount Saint Thomas flood map & planning overlays
A planning-constraint profile of Mount Saint Thomas
(Wollongong, NSW) - 0.55 km², mapped from live council and
state overlay data. This suburb is moderately constrained.
Profile updated 3 October 2026.
Suburb-wide figures; the free map shows which overlays touch your lot.
Constraint readout
0.55 km² - this suburb is moderately constrained by planning overlays.
Elevation hillshade with street names, clipped to Mount Saint Thomas'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 Mount Saint Thomas
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 1 a day
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.
Mount Saint Thomas at a glance
How Mount Saint Thomas is zoned
Buying in Mount Saint Thomas? 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 0.55 km², Mount Saint Thomas is moderately constrained by planning overlays. About 18% of the suburb sits within a mapped flood overlay, and 15% is flagged bushfire-prone. There is 1 heritage-listed site on record, and the dominant land-use zone is Low Density Residential. The median lot measures about 550 m² across 591 parcels.
Who lives in Mount Saint Thomas
Census 2021 figures published by the ABS for the Mount Saint Thomas 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 1006, and decile 6 within New South Wales. The national average is 1000.
Age profile
Share of Mount Saint Thomas's 1,449 residents in each ABS age band.
Population trend, 2001 to 2025
Estimated resident population of Wollongong - West, the wider ABS statistical area containing Mount Saint Thomas. There is no annual population series published at suburb level, so this describes the surrounding area rather than Mount Saint Thomas itself.
14,827 in 2001 to 17,595 in 2025, up 19%.
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.
Mount Saint Thomas 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 Mount Saint Thomas 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 24% of Mount Saint Thomas. 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 Mount Saint Thomas lot.
See what's in the $9 report →Mount Saint Thomas planning - frequently asked
Is Mount Saint Thomas flood-prone?
About 18% of Mount Saint Thomas falls within a mapped flood overlay, against the council-wide suburb average of 12%.
Is Mount Saint Thomas bushfire-prone?
Around 15% of Mount Saint Thomas is mapped as bushfire-prone, compared with a Wollongong average of 56%.
Is Mount Saint Thomas under a flight path?
Aircraft were observed below 3,000 ft over about 24% of Mount Saint Thomas, and over about 96% 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 2,000 ft, with an average of 5,500 ft. At the busiest point in the suburb about 1 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 Mount Saint Thomas?
The dominant planning zone in Mount Saint Thomas is Low Density Residential, though the suburb also includes Infrastructure and Public Recreation.
Does Mount Saint Thomas have heritage-listed places?
Mount Saint Thomas has 1 heritage-listed place on record.
What is the typical lot size in Mount Saint Thomas?
Across 591 surveyed parcels in Mount Saint Thomas, the median lot size is about 550 m².
Does Mount Saint Thomas have a train station?
There is no train station inside Mount Saint Thomas itself. The suburb is served by 23 bus stops.
What is the population of Mount Saint Thomas?
At the 2021 Census Mount Saint Thomas had 1,449 usual residents, with a median age of 37 and an average household size of 2.6 people. The wider Wollongong - West statistical area, which contains Mount Saint Thomas, went from 14,827 people in 2001 to 17,595 in 2025, up 19%.
Is Mount Saint Thomas an advantaged suburb?
On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Mount Saint Thomas scores 1006 and sits in decile 7 of 10 nationally and decile 6 within New South Wales (decile 1 is the most disadvantaged tenth, decile 10 the least).
What is the median household income in Mount Saint Thomas?
Median household income in Mount Saint Thomas was $1,835 a week at the 2021 Census, against $1,912 for the typical suburb in Wollongong. Median rent was $300 a week and the median mortgage repayment $2,167 a month.
Compare nearby suburbs
| Nearby suburb | Distance | Flood mapped | Bushfire-prone |
|---|---|---|---|
| Mangerton | 0.9 km | 9% | 23% |
| Coniston | 1.1 km | 42% | 10% |
| Spring Hill | 1.5 km | 10% | 0% |
| West Wollongong | 1.6 km | 8% | 4% |
| Wollongong | 2.3 km | 35% | <1% |
| Figtree | 2.5 km | 0% | 38% |
| Unanderra | 2.9 km | 0% | 17% |
| Gwynneville | 3.1 km | 28% | 7% |
| Keiraville | 3.4 km | 26% | 25% |
| Cringila | 3.4 km | 0% | 59% |