Silverdale flood map & planning overlays

A planning-constraint profile of Silverdale (Wollondilly, NSW) - 48.87 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.

Planning schematicSilverdale

Constraint readout

48.87 km² - this suburb is highly constrained by planning overlays.

Flood overlay <1%

4.0× council avg (0%) · #2 of 22 mapped council suburbs

Modelled flood depth held over parts of Silverdale

Bushfire-prone 92%

≈ council avg (93%) · #29 of 39 mapped council suburbs

Environmental41%

≈ council avg (38%) · #15 of 39 in council

Heritage sites 4 Noise corridor 40% Aircraft noise (ANEF) 40% Aircraft seen below 3,000 ft 19% Mostly Rural Landscape Bushfire 29th most affected of 39 →

Elevation hillshade with street names, clipped to Silverdale's boundary, with the flood, bushfire and environmental overlays drawn on top. Amber hatching is the published aircraft noise (ANEF) contour. 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 Silverdale

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.

Inside an aircraft noise contour

40%

40% of the suburb's land sits inside a published ANEF or airport-environs contour. Contours vary street by street, so whether a particular lot is inside one needs a property-level check.

Highest contour present

ANEF 25

Under AS 2021, land between ANEF 25 and 30 is generally unacceptable for new houses; 20 to 25 is conditionally acceptable with noise attenuation. The contour is a forecast, not a measurement at any one house.

Contours held

NSW planning (EPI) airport noise

Observed overflight - sampled 4 Sep to 2 Oct 2026

Under observed aircraft

67%

of the suburb, at or below 10,000 ft

Below 3,000 ft

19%

of the suburb's area

Lowest measured

500 ft

averaging 4,500 ft

Busiest square

~1 a day

1 a day below 3,000 ft · ±32% · area average
typical observed square 1 a day

Night movements: observed, lowest 1,000 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.

Silverdale at a glance

Parcels 2,128 Median lot 1,036 m² Mapped easements 11 Bus stops 68

How Silverdale is zoned

Rural Landscape 44%

National Parks and Nature Reserves 41%

Large Lot Residential 5%

Infrastructure 4%

Low Density Residential 3%

Primary Production 1%

Buying in Silverdale? 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 48.87 km², Silverdale is highly constrained by planning overlays. Flood mapping covers the suburb and none of it falls within a mapped flood overlay, and 92% is flagged bushfire-prone. There are 4 heritage-listed sites on record, and the dominant land-use zone is Rural Landscape. The median lot measures about 1,036 m² across 2,128 parcels.

Who lives in Silverdale

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

Population

4,543

usual residents, 2021

Median age

years

Median household income

$2,654

per week, Wollondilly suburb typical $2,250

Median rent

$500

per week, Wollondilly suburb typical $430

Median mortgage

$2,600

per month

Household size

3.3

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 9

most disadvantagedleast disadvantaged

Score 1055, and decile 8 within New South Wales. The national average is 1000.

Relative disadvantage (IRSD) Decile 9

most disadvantagedleast disadvantaged

Age profile

Share of Silverdale's 4,543 residents in each ABS age band.

0-4 7.8%

5-14 14.9%

15-19 7.4%

20-24 6.3%

25-34 13.4%

35-44 13.3%

45-54 14.1%

55-64 12.3%

65-74 7.2%

75-84 2.7%

85+ 0.7%

Population trend, 2001 to 2025

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

4,801 in 2001 to 7,544 in 2025, up 57%.

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.

Silverdale 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)	Inside a held contour	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 Silverdale 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 19% of Silverdale. 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 Silverdale. 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 Silverdale lot.

See what's in the $9 report →

Silverdale planning - frequently asked

Is Silverdale flood-prone?

Flood mapping covers Silverdale and less than 1% of the suburb falls within a mapped flood overlay (the council-wide suburb average is 0%). Published flood models are held over parts of Silverdale; the free check on the Flood Model Report page says whether one reaches a given address.

Is Silverdale bushfire-prone?

Around 92% of Silverdale is mapped as bushfire-prone, compared with a Wollondilly average of 93%.

Is Silverdale affected by aircraft noise?

About 40% of Silverdale sits inside a published aircraft noise contour, and the highest contour present is ANEF 25 - under AS 2021, land above ANEF 25 is generally considered unacceptable for new houses, and 20-25 conditionally acceptable with noise attenuation. ANEF contours are forecasts published per airport and used to control noise-sensitive development; they are not a measurement at any one house, and a property can sit under a flight path and outside every contour.

Is Silverdale under a flight path?

Aircraft were observed below 3,000 ft over about 19% of Silverdale, and over about 67% 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 4,500 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 Silverdale?

The dominant planning zone in Silverdale is Rural Landscape, though the suburb also includes National Parks and Nature Reserves and Large Lot Residential.

Does Silverdale have heritage-listed places?

Silverdale has 4 heritage-listed places on record.

What is the typical lot size in Silverdale?

Across 2,128 surveyed parcels in Silverdale, the median lot size is about 1,036 m². There are also 11 registered easements mapped in the suburb.

Does Silverdale have a train station?

There is no train station inside Silverdale itself. The suburb is served by 68 bus stops.

What is the population of Silverdale?

At the 2021 Census Silverdale had 4,543 usual residents, with a median age of 35 and an average household size of 3.3 people. The wider Warragamba - Silverdale statistical area, which contains Silverdale, went from 4,801 people in 2001 to 7,544 in 2025, up 57%.

Is Silverdale an advantaged suburb?

On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Silverdale scores 1055 and sits in decile 9 of 10 nationally and decile 8 within New South Wales (decile 1 is the most disadvantaged tenth, decile 10 the least).

What is the median household income in Silverdale?

Median household income in Silverdale was $2,654 a week at the 2021 Census, against $2,250 for the typical suburb in Wollondilly. Median rent was $500 a week and the median mortgage repayment $2,600 a month.

Compare nearby suburbs

Nearby suburb	Distance	Flood mapped	Bushfire-prone
Warragamba	4.0 km	2%	88%
Wallacia Liverpool	5.5 km	31%	88%
Greendale Liverpool	6.8 km	14%	96%
Werombi	7.1 km	0%	93%
Theresa Park	8.0 km	0%	74%
Brereton	8.3 km	<1%	97%
Massif Ridge Blue Mountains	10.1 km	<1%	100%
Bringelly Liverpool	10.7 km	3%	80%
Luddenham Liverpool	11.6 km	4%	80%
Orangeville	12.0 km	0%	97%

See all Wollondilly suburb profiles →