Great Marlow flood map & planning overlays
A planning-constraint profile of Great Marlow
(Clarence Valley, NSW) - 10.1 km², mapped from live council and
state overlay data. This suburb is highly constrained.
Profile updated 26 September 2026.
Suburb-wide figures; the free map shows which overlays touch your lot.
Constraint readout
10.1 km² - this suburb is highly constrained by planning overlays.
Elevation hillshade with street names, clipped to Great Marlow's boundary, with the flood, bushfire and environmental overlays drawn on top.
Nearby suburbs, nearest first
Aircraft noise and flight paths over Great Marlow
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.
Great Marlow at a glance
How Great Marlow is zoned
Buying in Great Marlow? 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 10.1 km², Great Marlow is highly constrained by planning overlays. About 99% of the suburb sits within a mapped flood overlay, and 84% is flagged bushfire-prone. There is 1 heritage-listed site on record, and the dominant land-use zone is Primary Production. The median lot measures about 5,632 m² across 125 parcels.
Who lives in Great Marlow
Census 2021 figures published by the ABS for the Great Marlow 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 987, and decile 5 within New South Wales. The national average is 1000.
Age profile
Share of Great Marlow's 184 residents in each ABS age band.
Population trend, 2001 to 2025
Estimated resident population of Grafton, the wider ABS statistical area containing Great Marlow. There is no annual population series published at suburb level, so this describes the surrounding area rather than Great Marlow itself.
18,513 in 2001 to 19,905 in 2025, up 8%.
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.
Great Marlow 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 26 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 Great Marlow 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 Great Marlow lot.
See what's in the $9 report →Great Marlow planning - frequently asked
Is Great Marlow flood-prone?
About 99% of Great Marlow falls within a mapped flood overlay, against the council-wide suburb average of 24%.
Is Great Marlow bushfire-prone?
Around 84% of Great Marlow is mapped as bushfire-prone, compared with a Clarence Valley average of 94%.
Is Great Marlow under a flight path?
No aircraft were observed over Great Marlow 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 Great Marlow?
The dominant planning zone in Great Marlow is Primary Production, though the suburb also includes Recreational Waterways and General Residential.
Does Great Marlow have heritage-listed places?
Great Marlow has 1 heritage-listed place on record.
What is the typical lot size in Great Marlow?
Across 125 surveyed parcels in Great Marlow, the median lot size is about 5,632 m². There are also 4 registered easements mapped in the suburb.
Does Great Marlow have a train station?
There is no train station inside Great Marlow itself. The suburb is served by 6 bus stops.
What is the population of Great Marlow?
At the 2021 Census Great Marlow had 184 usual residents, with a median age of 50 and an average household size of 2.5 people. The wider Grafton statistical area, which contains Great Marlow, went from 18,513 people in 2001 to 19,905 in 2025, up 8%.
Is Great Marlow an advantaged suburb?
On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Great Marlow scores 987 and sits in decile 6 of 10 nationally and decile 5 within New South Wales (decile 1 is the most disadvantaged tenth, decile 10 the least).
What is the median household income in Great Marlow?
Median household income in Great Marlow was $1,399 a week at the 2021 Census, against $1,187 for the typical suburb in Clarence Valley. Median rent was $345 a week and the median mortgage repayment $1,733 a month.
Compare nearby suburbs
| Nearby suburb | Distance | Flood mapped | Bushfire-prone |
|---|---|---|---|
| Alumy Creek | 2.3 km | 99% | 100% |
| Swan Creek | 2.3 km | 95% | 97% |
| Trenayr | 4.5 km | 39% | 92% |
| Junction Hill | 5.2 km | 57% | 67% |
| Grafton | 5.4 km | 91% | 10% |
| Carrs Creek | 5.7 km | 96% | 100% |
| Koolkhan | 5.8 km | 18% | 73% |
| Clarenza | 5.9 km | 36% | 97% |
| Southgate | 6.2 km | 60% | 95% |
| Crowther Island | 6.4 km | 100% | 52% |