Dee Why flood map & planning overlays
A planning-constraint profile of Dee Why (Northern Beaches, NSW) - 3.4 km², mapped from live council and state overlay data. This suburb is relatively unconstrained.
Everything below is suburb-wide. Overlays change block to block - see which ones actually touch your lot. The map is free.
Constraint readout
3.4 km² - this suburb is relatively unconstrained by planning overlays.
Elevation hillshade with street names, clipped to Dee Why's boundary, with the flood, bushfire and environmental overlays drawn on top. It shows where constraints fall; the interactive map shows them on your exact address.
Dee Why at a glance
How Dee Why is zoned
Buying in Dee Why? 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 3.4 km², Dee Why is relatively unconstrained by planning overlays. About 1% of the suburb sits within a mapped flood overlay, and 10% is flagged bushfire-prone. There are 20 heritage-listed sites on record, and the dominant land-use zone is Low Density Residential. The median lot measures about 650 m² across 2,487 parcels. These figures are suburb-wide - the overlays that actually apply to a given lot can differ block to block, which is what a property-level check tells you.
Who lives in Dee Why
Census 2021 figures published by the ABS for the Dee Why 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 1071, and decile 9 within New South Wales. The national average is 1000.
Age profile
Share of Dee Why's 23,354 residents in each ABS age band.
Population trend, 2001 to 2025
Estimated resident population of Dee Why - North, the wider ABS statistical area containing Dee Why. There is no annual population series published at suburb level, so this describes the surrounding area rather than Dee Why itself.
11,772 in 2001 to 19,332 in 2025, up 64%.
Source: Australian Bureau of Statistics. Census of Population and Housing 2021 (General Community Profile) and SEIFA 2021, both published at the Suburbs and Localities level; Regional Population (estimated resident population) at Statistical Area Level 2. Used under CC BY 4.0. Census counts of small populations are randomly adjusted by the ABS to protect confidentiality, so figures for small suburbs are indicative.
Dee Why data sources and coverage
Every figure below is an aggregate for the suburb boundary. “Not mapped” means LayeredGeo does not hold a source layer covering this suburb; it is never an all-clear for a particular property.
| 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 |
| Demographics | Available | Australian Bureau of Statistics (2021 Census and SEIFA) |
Profile last materially updated 5 August 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 Dee Why 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 →Dee Why planning - frequently asked
Where can I see a flood map of Dee Why?
The schematic on this page is a Dee Why flood map: the mapped flood overlays drawn over the suburb's terrain and street grid, covering about 1% of the suburb. Flood lines vary block to block, so for a specific property use the free interactive map - search any Dee Why address and it shows the flood, zoning and bushfire mapping on the exact lot boundary.
Is Dee Why flood-prone?
About 1% of Dee Why falls within a mapped flood overlay, against the council-wide suburb average of 12%. Flood overlays vary block to block, so whether a particular lot is affected needs a property-level check.
Is Dee Why bushfire-prone?
Yes - around 10% of Dee Why is mapped as bushfire-prone, compared with a Northern Beaches average of 47%. A bushfire-prone designation can trigger additional building requirements, so check the specific address.
What is the zoning in Dee Why?
The dominant planning zone in Dee Why is Low Density Residential, though the suburb also includes Medium Density Residential and Public Recreation. Zoning sets what you can build and do on a site, and can differ lot by lot.
Does Dee Why have heritage-listed places?
Dee Why has 20 heritage-listed places on record. Heritage listing affects what you can alter or demolish, so confirm whether a specific property is listed or near a heritage place.
What is the typical lot size in Dee Why?
Across 2,487 surveyed parcels in Dee Why, the median lot size is about 650 m². There are also 14 registered easements mapped in the suburb - an easement can restrict where you can build, so always check the title and overlays for the specific lot.
Does Dee Why have a train station?
There is no train station inside Dee Why itself. The suburb is served by 135 bus stops.
What is the population of Dee Why?
At the 2021 Census Dee Why had 23,354 usual residents, with a median age of 36 and an average household size of 2.3 people. The wider Dee Why - North statistical area, which contains Dee Why, went from 11,772 people in 2001 to 19,332 in 2025, up 64%. ABS publishes no annual population series for individual suburbs, so that trend describes the surrounding area rather than Dee Why alone.
Is Dee Why an advantaged suburb?
On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Dee Why scores 1071 and sits in decile 9 of 10 nationally and decile 9 within New South Wales - decile 1 being the most disadvantaged tenth of Australian suburbs and decile 10 the least. The national average score is 1000. SEIFA summarises income, education, occupation and housing across the whole suburb, so it describes the area, not any particular household in it.
What is the median household income in Dee Why?
Median household income in Dee Why was $2,106 a week at the 2021 Census, against $2,778 for the typical suburb in Northern Beaches. Median rent was $550 a week and the median mortgage repayment $2,457 a month. These are 2021 Census figures and have not been indexed to today.
Do I need a planning report for a Dee Why property?
A Dee Why planning report pulls every overlay - zoning, flood, bushfire, heritage and environmental - that touches a single lot, on live council and state data. The interactive map preview is free; a full PDF report is $9.
Compare nearby suburbs
| Nearby suburb | Distance | Flood mapped | Bushfire-prone |
|---|---|---|---|
| North Curl Curl | 1.4 km | 39% | 6% |
| Narraweena | 1.4 km | 5% | 8% |
| Collaroy | 2.0 km | Not mapped | 23% |
| Curl Curl | 2.1 km | 45% | 0% |
| Brookvale | 2.2 km | 21% | 18% |
| Collaroy Plateau | 2.3 km | Not mapped | 10% |
| Wheeler Heights | 2.6 km | Not mapped | 13% |
| Beacon Hill | 2.7 km | 2% | 49% |
| Freshwater | 2.8 km | 8% | 0% |
| Cromer | 3.2 km | Not mapped | 55% |