Swan Marsh flood map & planning overlays
Swan Marsh ranks 6th of 71 in Colac Otway for flood mapping, 35.5%.
Free map preview, then PDF reports from $9 - about the price of an iced latte on a public holiday.
A planning-constraint profile of Swan Marsh
(Colac Otway, VIC) - 54.06 km², mapped from live council and
state overlay data. This suburb is highly constrained.
Profile updated 24 October 2026.
Constraint readout
54.06 km² - this suburb is highly constrained by planning overlays.
Elevation hillshade with street names, clipped to Swan Marsh'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 Swan Marsh
The ANEF contour is a published planning forecast and observed overflight is what a sampled tracking feed recorded - neither describes any individual property.
Observed overflight - sampled 4 Sep to 24 Oct 2026
typical observed square 0 a day
Night movements: observed, lowest 2,500 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.
How this is measured
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.
Swan Marsh at a glance
How Swan Marsh is zoned
Selling in Swan Marsh? The zoning and planning overlays on this page are the controls a Section 32 vendor statement discloses.
Across its 54.06 km², Swan Marsh is highly constrained by planning overlays. About 36% of the suburb sits within a mapped flood overlay, and 100% is flagged bushfire-prone. There are 2 heritage-listed sites on record, and the dominant land-use zone is Farming Zone (FZ). The median lot measures about 84,749 m² across 259 parcels.
Who lives in Swan Marsh
Census 2021 figures published by the ABS for the Swan Marsh 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 1028, and decile 8 within Victoria. The national average is 1000.
Age profile
Share of Swan Marsh's 127 residents in each ABS age band.
Population trend, 2001 to 2025
Estimated resident population of Colac Surrounds, the wider ABS statistical area containing Swan Marsh. There is no annual population series published at suburb level, so this describes the surrounding area rather than Swan Marsh itself.
5,829 in 2001 to 5,670 in 2025, down 3%.
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.
Swan Marsh 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 | Vicmap Planning and Victorian Government spatial services |
| Bushfire-prone mapping | Mapped | Vicmap Planning and Victorian Government spatial services |
| Zoning | Mapped | Vicmap Planning and Victorian Government spatial services |
| Heritage and environment | Mapped where published | Vicmap Planning and Victorian Government spatial services |
| Aircraft noise contours (ANEF) | Not held | Vicmap Planning and Victorian Government spatial services, 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 24 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 Swan Marsh 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.
See what's in the $9 report →Aircraft have been seen below 3,000 ft over about 15% of Swan Marsh. 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 the indicative soil reactivity range to expect for a Swan Marsh lot.
Swan Marsh planning - frequently asked
Is Swan Marsh flood-prone?
About 36% of Swan Marsh falls within a mapped flood overlay, against the council-wide suburb average of 12%.
Is Swan Marsh bushfire-prone?
Around 100% of Swan Marsh is mapped as bushfire-prone, compared with a Colac Otway average of 97%.
Is Swan Marsh under a flight path?
Aircraft were observed below 3,000 ft over about 15% of Swan Marsh, and over about 30% at any altitude up to 10,000 ft, in the period sampled (4 Sep 2026 to 24 Oct 2026). The lowest measured aircraft was at 1,000 ft, with an average of 3,000 ft. At the busiest point in the suburb about 0 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 Swan Marsh?
The dominant planning zone in Swan Marsh is Farming Zone (FZ), though the suburb also includes Transport Zone (TRZ1) and Township Zone (TZ).
Does Swan Marsh have heritage-listed places?
Swan Marsh has 2 heritage-listed places on record.
What is the typical lot size in Swan Marsh?
Across 259 surveyed parcels in Swan Marsh, the median lot size is about 84,749 m². There are also 122 registered easements mapped in the suburb.
What is the population of Swan Marsh?
At the 2021 Census Swan Marsh had 127 usual residents, with a median age of 45 and an average household size of 2.6 people. The wider Colac Surrounds statistical area, which contains Swan Marsh, went from 5,829 people in 2001 to 5,670 in 2025, down 3%.
Is Swan Marsh an advantaged suburb?
On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Swan Marsh scores 1028 and sits in decile 8 of 10 nationally and decile 8 within Victoria (decile 1 is the most disadvantaged tenth, decile 10 the least).
What is the median household income in Swan Marsh?
Median household income in Swan Marsh was $1,458 a week at the 2021 Census, against $1,443 for the typical suburb in Colac Otway. Median rent was $200 a week and the median mortgage repayment $1,040 a month.
Compare nearby suburbs
| Nearby suburb | Distance | Flood mapped | Bushfire-prone |
|---|---|---|---|
| Stonyford | 6.2 km | 1% | 100% |
| Bungador | 6.5 km | 13% | 100% |
| Pirron Yallock | 6.6 km | 22% | 100% |
| Pomborneit East Corangamite |
9.2 km | 60% | 57% |
| Irrewillipe | 9.6 km | 5% | 100% |
| Carpendeit Corangamite |
10.1 km | 2% | 100% |
| Pomborneit Corangamite |
10.2 km | <1% | 100% |
| Nalangil | 10.3 km | 25% | 98% |
| Irrewillipe East | 13.1 km | <1% | 100% |
| South Purrumbete Corangamite |
13.3 km | 3% | 100% |