Semaphore flood map & planning overlays
A planning-constraint profile of Semaphore
(City of Port Adelaide Enfield, SA) - 1.24 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
1.24 km² - this suburb is highly constrained by planning overlays.
Elevation hillshade with street names, clipped to Semaphore'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 Semaphore
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 26 Sep 2026
typical observed square 2 a day
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.
Semaphore at a glance
How Semaphore is zoned
Selling in Semaphore? The zone and overlays on this page are the Planning and Design Code controls a Form 1 vendor's statement has to disclose.
Across its 1.24 km², Semaphore is highly constrained by planning overlays. About 23% of the suburb sits within a mapped flood overlay. There are 60 heritage-listed sites on record, and the dominant land-use zone is Established Neighbourhood. The median lot measures about 396 m² across 1,635 parcels.
Who lives in Semaphore
Census 2021 figures published by the ABS for the Semaphore 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 1021, and decile 8 within South Australia. The national average is 1000.
Age profile
Share of Semaphore's 2,749 residents in each ABS age band.
Population trend, 2001 to 2025
Estimated resident population of Largs Bay - Semaphore, the wider ABS statistical area containing Semaphore. There is no annual population series published at suburb level, so this describes the surrounding area rather than Semaphore itself.
13,971 in 2001 to 15,765 in 2025, up 13%.
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.
Semaphore 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 | the South Australian Planning and Design Code and Location SA spatial data |
| Bushfire-prone mapping | Mapped | the South Australian Planning and Design Code and Location SA spatial data |
| Zoning | Mapped | the South Australian Planning and Design Code and Location SA spatial data |
| Heritage and environment | Mapped where published | the South Australian Planning and Design Code and Location SA spatial data |
| Aircraft noise contours (ANEF) | Not held | the South Australian Planning and Design Code and Location SA spatial data, 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 Semaphore 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 91% of Semaphore. 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 Semaphore lot.
See what's in the $9 report →Semaphore planning - frequently asked
Is Semaphore flood-prone?
About 23% of Semaphore falls within a mapped flood overlay, against the council-wide suburb average of 17%.
Is Semaphore bushfire-prone?
Bushfire mapping covers Semaphore and little to none of it is mapped as bushfire-prone.
Is Semaphore under a flight path?
Aircraft were observed below 3,000 ft over about 91% of Semaphore, and over about 100% at any altitude up to 10,000 ft, in the period sampled (4 Sep 2026 to 26 Sep 2026). The lowest measured aircraft was at 500 ft, with an average of 3,000 ft. At the busiest point in the suburb about 2 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 Semaphore?
The dominant planning zone in Semaphore is Established Neighbourhood, though the suburb also includes Open Space and Suburban Activity Centre.
Does Semaphore have heritage-listed places?
Semaphore has 60 heritage-listed places on record.
What is the typical lot size in Semaphore?
Across 1,635 surveyed parcels in Semaphore, the median lot size is about 396 m².
Does Semaphore have a train station?
There is no train station inside Semaphore itself. The suburb is served by 14 bus stops.
What is the population of Semaphore?
At the 2021 Census Semaphore had 2,749 usual residents, with a median age of 50 and an average household size of 2.2 people. The wider Largs Bay - Semaphore statistical area, which contains Semaphore, went from 13,971 people in 2001 to 15,765 in 2025, up 13%.
Is Semaphore an advantaged suburb?
On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Semaphore scores 1021 and sits in decile 7 of 10 nationally and decile 8 within South Australia (decile 1 is the most disadvantaged tenth, decile 10 the least).
What is the median household income in Semaphore?
Median household income in Semaphore was $1,718 a week at the 2021 Census, against $1,459 for the typical suburb in City of Port Adelaide Enfield. Median rent was $320 a week and the median mortgage repayment $1,733 a month.
Compare nearby suburbs
| Nearby suburb | Distance | Flood mapped | Bushfire-prone |
|---|---|---|---|
| Exeter | 0.7 km | 24% | 0% |
| Glanville | 0.9 km | 41% | 0% |
| Semaphore South | 1.0 km | 30% | 0% |
| Ethelton | 1.3 km | 35% | 0% |
| New Port | 1.4 km | 17% | 0% |
| Birkenhead | 1.6 km | 22% | 0% |
| Largs Bay | 1.7 km | 25% | 0% |
| Peterhead | 1.7 km | 38% | 0% |
| Semaphore Park City of Charles Sturt |
2.4 km | 24% | 0% |
| Port Adelaide | 2.7 km | 32% | 0% |