Flood Risk in Semaphore South, SA: 2026 Assessment

Semaphore South, South Australia· UNKNOWN
Semaphore South faces a moderate risk of flooding, primarily from heavy rainfall and potential stormwater runoff. The flat topography and proximity to coastal areas contribute to this risk.Updated 3 Apr 2026

Flood Risk Score

6.0/10

Semaphore South faces a moderate risk of flooding, primarily from heavy rainfall and potential stormwater runoff. The flat topography and proximity to coastal areas contribute to this risk.

Key Facts

Flood Risk
Semaphore South faces a moderate risk of flooding, primarily from heavy rainfall and potential stormwater runoff. The flat topography and proximity to coastal areas contribute to this risk.
Trend
increasing
Suburb
Semaphore South, SA
Overall Risk
Medium
Postcode
5019
Highest high-risk exposure
22.4% of land (bushfire)

Flood Risk Analysis

Semaphore South, located in South Australia, has a notable flood risk profile based on available data including proximity to waterways, elevation, and historical flood events. The Bureau of Meteorology (BOM) maintains river height and flood warning data for catchments across South Australia.

The area is susceptible to tidal inundation and stormwater flooding.

Semaphore South faces a moderate risk of flooding, primarily from heavy rainfall and potential stormwater runoff. The flat topography and proximity to coastal areas contribute to this risk.

For a comprehensive property-specific flood assessment including address-level elevation data, flood overlay mapping, and insurance cost estimates, use the ClimateNest full analysis tool. General suburb data cannot replace a site-specific evaluation.

Semaphore South sits within ClimateNest's suburb-level hazard model for flood risk. 2.9% of the suburb's land area is mapped in high-risk flood zones and 91.2% in moderate-risk zones, based on the national hazard overlay. Exposure at this scale varies street by street, which is why an address-level check matters before you buy or insure a specific property in Semaphore South.

Semaphore South (postcode 5019) is tracked in ClimateNest's suburb hazard model, which maps the share of the suburb's land exposed to each hazard at high and moderate levels. The suburb's highest high-risk exposures are bushfire (22.4% of land in high-risk zones), surface flood (11.8% of land in high-risk zones), riverine flood (2.9% of land in high-risk zones). Exposure is not uniform across Semaphore South — individual properties can sit well above or below these averages, so an address-level check is recommended before buying, selling or insuring.

Local Hazard Evidence

Nearest WaterwayPort River
Elevation Range0-5 meters
Flood Zone ClassificationCoastal Flood Zone

Historical Events

2022
Minor

Heavy rainfall caused localized flooding in low-lying areas.

Adaptation & Mitigation Actions

Improve stormwater drainage

Near-term

Upgrade stormwater infrastructure to reduce the risk of flash flooding.

Est. cost: Medium

Implement heatwave early warning system

Immediate

Develop a system to alert vulnerable residents during extreme heat events.

Est. cost: Low

Protect coastal areas

Long-term

Invest in coastal protection measures to mitigate erosion and sea level rise impacts.

Est. cost: High

Promote water conservation

Near-term

Encourage residents to conserve water to reduce strain on water resources during droughts.

Est. cost: Low

Council & Emergency Services

City of Port Adelaide Enfield
Emergency Services

Data last updated: 3 April 2026

Explore Semaphore South Risk Reports

Frequently Asked Questions

Is Semaphore South at risk of flooding?

Based on available data, Semaphore South has a notable flood risk profile. Flood risk varies by address — check your specific property for precise flood zone mapping and elevation data with ClimateNest.

What flood insurance costs can I expect in Semaphore South?

Insurance costs for flood cover in Semaphore South depend on the property's flood zone classification, elevation, and proximity to waterways. ClimateNest provides address-level insurance cost estimates based on your property's specific hazard exposure.

Does flood risk affect property values in Semaphore South?

Yes, flood risk can affect property values in Semaphore South. Properties in mapped flood zones may experience lower buyer demand, reduced valuations, and higher insurance costs. Lenders increasingly assess flood exposure as part of mortgage risk evaluation.

How does elevation affect flood risk in Semaphore South?

Elevation is a critical factor in flood risk. Properties at higher elevations within Semaphore South typically have lower flood exposure than those near waterways or in low-lying areas. Address-level elevation data combined with BOM flood mapping provides the most accurate picture.

What share of Semaphore South is exposed to high bushfire risk?

ClimateNest's hazard overlay maps 22.4% of Semaphore South in high-risk zones for bushfire, with a further 59.2% in moderate-risk zones. Suburb-level exposure is not uniform — individual properties can differ from these averages, so an address-level check is recommended.

Is Semaphore South Safe from Climate Risk?

Enter your address below for an instant climate risk assessment for Semaphore South, South Australia, covering flood, bushfire, sea level rise and more.

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What A$69 could save you from

$7.2B
2022 insured disaster losses*
$300B+
climate risk to property by 2050*
30-120%
insurance premium increases in high-risk areas*

*Industry sources: ICA, APRA, RBA

Full report from A$69 · Australian addresses only · 8 hazard scores · Insurance trajectory · 2030 & 2050 projections