New South Wales has been battered by a severe weather system this week, causing widespread disruption across the state and renewing concerns about the growing impact of extreme weather events. From Sydney to the South Coast, cities and towns have faced torrential rainfall, damaging winds, coastal erosion and flash flooding, with the aftermath still unfolding as conditions begin to ease.
A rapidly intensifying storm
The system, which developed rapidly off the east coast, brought a complex mix of hazards to NSW. While the Bureau of Meteorology avoided the more alarmist term “bomb cyclone”, the storm met many of the technical criteria for one. Winds exceeded 130km/h in exposed coastal areas, and multiple locations recorded over 200mm of rain in just 48 hours.
Coastal communities from Seal Rocks to the Victorian border were placed on high alert for hazardous surf and erosion, with Port Kembla and Eden both recording wave heights of up to 13m. Sydney’s coastline, including Batemans Bay and Manly, also experienced significant wave activity, raising concerns about infrastructure resilience in these exposed areas.
Flooding across Greater Sydney and the South Coast
Flooding became a major concern as the storm progressed. The Hawkesbury-Nepean Valley saw rapid rises in river levels, prompting flood warnings in Camden, Penrith and North Richmond. Authorities confirmed that the Warragamba Dam, Sydney’s primary water reservoir, spilled over on Thursday morning following days of persistent rainfall. While the overflow was described as moderate, it echoed similar events in recent years that have impacted communities downstream.
In the Shoalhaven region, localised flash flooding triggered multiple flood rescues. The NSW State Emergency Service responded to more than 3,400 incidents across the state, with fallen trees, damaged roofs and power outages dominating callouts.
Power and transport disruptions
Energy providers Endeavour Energy and Ausgrid reported major outages, with over 35,000 properties affected at the peak of the storm. While the majority of customers have now been reconnected, around 1,600 properties remain without electricity due to complex faults or restricted access. Crews continue to work around the clock to restore power, particularly in the Central Coast and Newcastle regions.
Transport infrastructure also struggled under the strain. Sydney Airport experienced nearly 300 flight cancellations over two days, while fallen trees and power failures disrupted rail and ferry services across Greater Sydney and the Illawarra.
Longer-term implications
Climate scientists have once again drawn attention to the role of warm sea surface temperatures in driving the intensity of this event. With ocean temperatures off Australia’s east coast well above average, low-pressure systems are absorbing more moisture and energy, resulting in stronger, longer-lasting storms. For many NSW communities, particularly those in flood-prone zones, these events are becoming more frequent and more damaging, both financially and psychologically.
The clean-up from the storm chaos in New South Wales will take time, and for some areas, the full impact won’t be known for days. What is clear, however, is that resilience planning, infrastructure investment and climate adaptation will need to remain at the forefront of policy and planning across New South Wales.
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