Flood Risk in Onslow, WA: 2026 Assessment

Onslow, located in Western 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 Western Australia.

Onslow is located on a coastal floodplain, making it susceptible to flooding from both riverine and coastal sources.

Onslow faces a moderate risk of flooding, primarily from heavy rainfall events and storm surges. The town's low-lying coastal location makes it vulnerable to inundation.

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.

Onslow sits within ClimateNest's suburb-level hazard model for flood risk. 4.2% of the suburb's land area is mapped in high-risk flood zones and 69.5% 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 Onslow.

Onslow (postcode 6710) 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 (9.2% of land in high-risk zones), surface flood (6.1% of land in high-risk zones), extreme wind (5.2% of land in high-risk zones). Exposure is not uniform across Onslow — individual properties can sit well above or below these averages, so an address-level check is recommended before buying, selling or insuring.