Castle Hill flood map & planning overlays

A planning-constraint profile of Castle Hill (The Hills Shire, NSW) - 18.88 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.

Planning schematicCastle Hill

Constraint readout

18.88 km² - this suburb is moderately constrained by planning overlays.

Flood overlay 0%

below council avg (9%) · #17 of 23 mapped council suburbs

Modelled flood depth held over parts of Castle Hill

Bushfire-prone 19%

below council avg (62%) · #18 of 23 mapped council suburbs

Environmental1%

below council avg (6%) · #13 of 23 in council

Heritage sites 37 Aircraft seen below 3,000 ft 88% Mostly Low Density Residential Bushfire 18th most affected of 23 →

Elevation hillshade with street names, clipped to Castle Hill'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 Castle Hill

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

Under observed aircraft

100%

of the suburb, at or below 10,000 ft

Below 3,000 ft

88%

of the suburb's area

Lowest measured

500 ft

averaging 3,000 ft · ground movements recorded: on or beside an aerodrome

Busiest square

~15 a day

10 a day below 3,000 ft · ±23%
typical observed square 4 a day

Night movements: observed, lowest 1,500 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.

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.

Castle Hill at a glance

Parcels 11,199 Median lot 804 m² Mapped easements 54 Train Castle Hill Station, Hills Showground Station Bus stops 501 Landslide overlay 2%

How Castle Hill is zoned

Low Density Residential 52%

Public Recreation 11%

Medium Density Residential 10%

Environmental Living 8%

High Density Residential 4%

General Industrial 4%

Buying in Castle Hill? 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 18.88 km², Castle Hill is moderately constrained by planning overlays. Flood mapping covers the suburb and none of it falls within a mapped flood overlay, and 19% is flagged bushfire-prone. There are 37 heritage-listed sites on record, and the dominant land-use zone is Low Density Residential. The median lot measures about 804 m² across 11,199 parcels.

Who lives in Castle Hill

Census 2021 figures published by the ABS for the Castle Hill suburb boundary itself, not a wider region.

Population

40,874

usual residents, 2021

Median age

years

Median household income

$2,551

per week, The Hills Shire suburb typical $2,650

Median rent

$560

per week, The Hills Shire suburb typical $560

Median mortgage

$3,000

per month

Household size

3.0

people, average

Socio-economic standing

ABS SEIFA 2021 ranks every Australian suburb. Decile 1 is the most disadvantaged tenth of the country, decile 10 the least.

Advantage and disadvantage (IRSAD) Decile 10

most disadvantagedleast disadvantaged

Score 1124, and decile 10 within New South Wales. The national average is 1000.

Relative disadvantage (IRSD) Decile 10

most disadvantagedleast disadvantaged

Age profile

Share of Castle Hill's 40,874 residents in each ABS age band.

0-4 4.3%

5-14 14.5%

15-19 6.7%

20-24 5.8%

25-34 8.3%

35-44 14.2%

45-54 14.3%

55-64 12.0%

65-74 10.4%

75-84 6.2%

85+ 3.4%

Population trend, 2001 to 2025

Estimated resident population of Castle Hill - North, the wider ABS statistical area containing Castle Hill. There is no annual population series published at suburb level, so this describes the surrounding area rather than Castle Hill itself.

11,141 in 2001 to 12,973 in 2025, up 16%.

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.

Castle Hill 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 Castle Hill 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 88% of Castle Hill. The report's Aircraft Overflight page narrows that to the address itself: how many aircraft a day, how low, and at what heights.

Published flood models are held over parts of Castle Hill. The free check tells you whether one reaches an address; where it does, a Flood Model Report is +$9 with the planning report.

Building or pricing a slab? The $119 geotechnical desktop report covers geology, soils, bores and an indicative AS 2870 site class for a Castle Hill lot.

See what's in the $9 report →

Castle Hill planning - frequently asked

Is Castle Hill flood-prone?

Flood mapping covers Castle Hill and none of the suburb falls within a mapped flood overlay (the council-wide suburb average is 9%). Published flood models are held over parts of Castle Hill; the free check on the Flood Model Report page says whether one reaches a given address.

Is Castle Hill bushfire-prone?

Around 19% of Castle Hill is mapped as bushfire-prone, compared with a The Hills Shire average of 62%.

Is Castle Hill under a flight path?

Aircraft were observed below 3,000 ft over about 88% of Castle Hill, and over about 100% 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 500 ft, with an average of 3,000 ft. At the busiest point in the suburb about 15 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 Castle Hill?

The dominant planning zone in Castle Hill is Low Density Residential, though the suburb also includes Public Recreation and Medium Density Residential.

Does Castle Hill have heritage-listed places?

Castle Hill has 37 heritage-listed places on record.

What is the typical lot size in Castle Hill?

Across 11,199 surveyed parcels in Castle Hill, the median lot size is about 804 m². There are also 54 registered easements mapped in the suburb.

Does Castle Hill have a train station?

Yes - Castle Hill has 2 train stations: Castle Hill Station, Hills Showground Station. It is also served by 501 bus stops.

What is the population of Castle Hill?

At the 2021 Census Castle Hill had 40,874 usual residents, with a median age of 42 and an average household size of 3.0 people. The wider Castle Hill - North statistical area, which contains Castle Hill, went from 11,141 people in 2001 to 12,973 in 2025, up 16%.

Is Castle Hill an advantaged suburb?

On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Castle Hill scores 1124 and sits in decile 10 of 10 nationally and decile 10 within New South Wales (decile 1 is the most disadvantaged tenth, decile 10 the least).

What is the median household income in Castle Hill?

Median household income in Castle Hill was $2,551 a week at the 2021 Census, against $2,650 for the typical suburb in The Hills Shire. Median rent was $560 a week and the median mortgage repayment $3,000 a month.

Compare nearby suburbs

Nearby suburb	Distance	Flood mapped	Bushfire-prone
Baulkham Hills	3.0 km	0%	13%
Glenhaven	3.1 km	0%	71%
Norwest	3.2 km	0%	0%
West Pennant Hills	3.7 km	0%	36%
Bella Vista	4.1 km	<1%	0%
Cherrybrook Hornsby	4.3 km	0%	40%
Kellyville	4.5 km	0%	9%
North Rocks City Of Parramatta	5.3 km	0%	48%
Winston Hills City Of Parramatta	5.5 km	0%	9%
Northmead City Of Parramatta	6.0 km	0%	22%

See all The Hills Shire suburb profiles →