Iona flood map & planning overlays

The schematic on this page is a Iona flood map: the mapped flood overlays drawn over the suburb's terrain and street grid, covering about 100% of the suburb. Flood lines vary block to block, so for a specific property use the free interactive map - search any Iona address and it shows the flood, zoning and bushfire mapping on the exact lot boundary.

About 100% of Iona falls within a mapped flood overlay, against the council-wide suburb average of 42%. Flood overlays vary block to block, so whether a particular lot is affected needs a property-level check.

Around 100% of Iona is mapped as bushfire-prone, compared with a Cardinia average of 98%. A bushfire-prone designation can trigger additional building requirements, so check the specific address.

The dominant planning zone in Iona is Special Use Zone (SUZ1), though the suburb also includes Green Wedge Zone (GWZ1) and Public Use Zone (PUZ1). Zoning sets what you can build and do on a site, and can differ lot by lot.

Iona has 5 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.

Across 238 surveyed parcels in Iona, the median lot size is about 80,862 m². There are also 20 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.

At the 2021 Census Iona had 240 usual residents, with a median age of 47 and an average household size of 2.8 people. The wider Bunyip - Garfield statistical area, which contains Iona, went from 7,445 people in 2001 to 10,366 in 2025, up 39%. ABS publishes no annual population series for individual suburbs, so that trend describes the surrounding area rather than Iona alone.

On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Iona scores 1001 and sits in decile 6 of 10 nationally and decile 6 within Victoria - 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.

Median household income in Iona was $1,924 a week at the 2021 Census, against $1,976 for the typical suburb in Cardinia. Median rent was $250 a week and the median mortgage repayment $2,140 a month. These are 2021 Census figures and have not been indexed to today.

An Iona planning report pulls every overlay - zoning, flood, bushfire, heritage, environmental and noise - that touches a single lot, on live council and state data. The interactive map preview is free; the full PDF report is $9.