Mellong flood map & planning overlays
A planning-constraint profile of Mellong
(Hawkesbury, NSW) - 402.18 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
402.18 km² - this suburb is highly constrained by planning overlays.
Elevation hillshade with street names, clipped to Mellong'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 Mellong
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
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.
Mellong at a glance
How Mellong is zoned
Buying in Mellong? 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 402.18 km², Mellong 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 National Parks and Nature Reserves. The median lot measures about 664,460 m² across 40 parcels.
Who lives in Mellong
Census 2021 figures published by the ABS for the Mellong 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 973, and decile 4 within New South Wales. The national average is 1000.
Population trend, 2001 to 2025
Estimated resident population of Bilpin - Colo - St Albans, the wider ABS statistical area containing Mellong. There is no annual population series published at suburb level, so this describes the surrounding area rather than Mellong itself.
2,518 in 2001 to 2,781 in 2025, up 10%.
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.
Mellong 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 Mellong 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.
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 Mellong lot.
See what's in the $9 report →Mellong planning - frequently asked
Is Mellong flood-prone?
Flood mapping covers Mellong and none of the suburb falls within a mapped flood overlay (the council-wide suburb average is 24%).
Is Mellong bushfire-prone?
Around 100% of Mellong is mapped as bushfire-prone, compared with a Hawkesbury average of 84%.
Is Mellong under a flight path?
Aircraft were observed over about 14% of Mellong in the period sampled, but only above 3,000 ft - the lowest measured was 1,500 ft. 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 Mellong?
The dominant planning zone in Mellong is National Parks and Nature Reserves, though the suburb also includes Primary Production and Infrastructure.
Does Mellong have heritage-listed places?
No heritage-listed places are on record within Mellong.
What is the typical lot size in Mellong?
Across 40 surveyed parcels in Mellong, the median lot size is about 664,460 m². There are also 2 registered easements mapped in the suburb.
Is Mellong an advantaged suburb?
On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Mellong scores 973 and sits in decile 5 of 10 nationally and decile 4 within New South Wales (decile 1 is the most disadvantaged tenth, decile 10 the least).
Compare nearby suburbs
| Nearby suburb | Distance | Flood mapped | Bushfire-prone |
|---|---|---|---|
| Higher Macdonald | 16.2 km | 0% | 100% |
| Womerah | 16.4 km | 0% | 100% |
| Yengo Cessnock |
17.4 km | 4% | 100% |
| Garland Valley Singleton |
19.2 km | Not mapped | 100% |
| Wirraba Lithgow City |
20.0 km | 0% | 100% |
| Colo Heights | 21.6 km | 0% | 100% |
| Perrys Crossing | 23.9 km | 0% | 100% |
| Upper Macdonald | 24.8 km | 0% | 100% |
| Putty Singleton |
25.5 km | 0% | 100% |
| Fernances | 27.7 km | 0% | 100% |