St Helens Plains flood map & planning overlays
A 35.5% flood share puts St Helens Plains 4th of 35 in Horsham.
Free map preview, then PDF reports from $9 - about the price of an iced latte on a public holiday.
A planning-constraint profile of St Helens Plains
(Horsham, VIC) - 134.58 km², mapped from live council and
state overlay data. This suburb is highly constrained.
Profile updated 24 October 2026.
Constraint readout
134.58 km² - this suburb is highly constrained by planning overlays.
Elevation hillshade with street names, clipped to St Helens Plains'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 St Helens Plains
The ANEF contour is a published planning forecast and observed overflight is what a sampled tracking feed recorded - neither describes any individual property.
Observed overflight - sampled 4 Sep to 24 Oct 2026
Night movements: observed, lowest 8,500 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.
How this is measured
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.
St Helens Plains at a glance
How St Helens Plains is zoned
Selling in St Helens Plains? The zoning and planning overlays on this page are the controls a Section 32 vendor statement discloses.
Across its 134.58 km², St Helens Plains is highly constrained by planning overlays. About 36% of the suburb sits within a mapped flood overlay, and 99% is flagged bushfire-prone. The dominant land-use zone is Farming Zone (FZ). The median lot measures about 161,908 m² across 462 parcels.
Who lives in St Helens Plains
Census 2021 figures published by the ABS for the St Helens Plains 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 1041, and decile 8 within Victoria. The national average is 1000.
Population trend, 2001 to 2025
Estimated resident population of Horsham Surrounds, the wider ABS statistical area containing St Helens Plains. There is no annual population series published at suburb level, so this describes the surrounding area rather than St Helens Plains itself.
3,565 in 2001 to 3,399 in 2025, down 5%.
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.
St Helens Plains 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 | Vicmap Planning and Victorian Government spatial services |
| Bushfire-prone mapping | Mapped | Vicmap Planning and Victorian Government spatial services |
| Zoning | Mapped | Vicmap Planning and Victorian Government spatial services |
| Heritage and environment | Mapped where published | Vicmap Planning and Victorian Government spatial services |
| Aircraft noise contours (ANEF) | Not held | Vicmap Planning and Victorian Government spatial services, 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 24 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 St Helens Plains 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 →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 the indicative soil reactivity range to expect for a St Helens Plains lot.
St Helens Plains planning - frequently asked
Is St Helens Plains flood-prone?
About 36% of St Helens Plains falls within a mapped flood overlay, against the council-wide suburb average of 16%.
Is St Helens Plains bushfire-prone?
Around 99% of St Helens Plains is mapped as bushfire-prone, compared with a Horsham average of 98%.
Is St Helens Plains under a flight path?
Aircraft were observed over about 2% of St Helens Plains in the period sampled, but only above 3,000 ft - the lowest measured was 6,000 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 St Helens Plains?
The dominant planning zone in St Helens Plains is Farming Zone (FZ), though the suburb also includes Public Conservation and Resource Zone (PCRZ) and Public Use Zone (PUZ1).
Does St Helens Plains have heritage-listed places?
No heritage-listed places are on record within St Helens Plains.
What is the typical lot size in St Helens Plains?
Across 462 surveyed parcels in St Helens Plains, the median lot size is about 161,908 m². There are also 42 registered easements mapped in the suburb.
Is St Helens Plains an advantaged suburb?
On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), St Helens Plains scores 1041 and sits in decile 8 of 10 nationally and decile 8 within Victoria (decile 1 is the most disadvantaged tenth, decile 10 the least).
Compare nearby suburbs
| Nearby suburb | Distance | Flood mapped | Bushfire-prone |
|---|---|---|---|
| Drung | 9.6 km | 29% | 100% |
| Lubeck Yarriambiack |
11.3 km | 22% | 100% |
| Longerenong | 13.1 km | 60% | 100% |
| Bungalally | 15.3 km | 9% | 100% |
| Wal Wal Northern Grampians |
15.4 km | 40% | 100% |
| Dadswells Bridge | 15.5 km | 47% | 100% |
| Riverside | 17.6 km | 72% | 100% |
| Laharum | 18.2 km | 10% | 100% |
| Murtoa Yarriambiack |
20.3 km | 8% | 100% |
| Haven | 21.1 km | 11% | 100% |