IGEM Report 1: 2017-18 - THE CYCLONE DEBBIE REVIEW

The Cyclone Debbie Review

By around 3.00pm the storm tide figures had moderated slightly to a worse case of 2.5 metres and most likely tide of 0.8 metres. Around 6.15pm on Monday 27 March, and after discussion between state and local officials, advice to residents was further revised. As a consequence directed evacuations of those in the Green and Red zones in the Mackay area and associated beaches commenced. The Mackay group requested an EA to convey the direction to evacuate immediately to family and friends. These messages were reiterated on the council’s Facebook page. Although Debbie crossed the coast north of Mackay, there were areas that were substantially impacted by the event. The area suffered the most power outages in the north but around 40 per cent of it remained connected. 42 While the ports remained closed, by Wednesday 29 March its airport was open with restrictions. 43 Thunderstorms exacerbated widespread rainfall totals of 250-700mm in 48 hours in the Pioneer River catchment. The Pioneer reached a minor flood peak in Mackay and major flood levels 30 kilometres to the west at Mirani. On the Sarina Range a number of residents were isolated. The Mackay local group also had challenges with trecord flooding that affected Eton and other areas, and outflows from the Kinchant Dam. The IGEM recognises that a separate assessment of the issues surrounding Kinchant Dam has been undertaken by the Office of the Chief Scientist. We note that the independent report found that the Kinchant Dam would have had little or no significant impact on local flooding following Debbie.

Isaac

The three concurrent events

Isaac Regional Council also experienced the effects of dangerous winds, extraordinary high intensity rainfall and rapid onset flooding across the majority of the region. Although only few residential properties were damaged, significant social and economic impacts have been felt. A number of agricultural properties, a school and a small business, such as the service station, became isolated due to flooding. Significant damage to transport infrastructure (road and rail) was evident. This caused major disruption to supply and product movements. Response and recovery efforts were challenged, exacerbated by communication and power failures. As a result, major economic impacts of state significance are evident in the local agricultural and mining industries. The Isaac LDMG had undertaken some planning activities in conjunction with regional mining companies. Subsequent to the event, the group has identified that improved integration of plans will enhance operational activity. This will lead to decisions that are better informed and enhance the understanding of local capacity, including the utilisation of resources (e.g. equipment) in response. The LDMG has also identified a number of other challenges that will require longer term partnerships and a strategic outlook to mitigate the effects of future disaster events. Unlike recent severe tropical cyclones experienced in Queensland, Debbie moved comparatively slowly, maintaining cyclone strength for over 24 hours in some areas. The slowness in crossing the coast resulted in staff on duty for days in some cases, and put particular pressure on key people for an extended period. Despite the pressure, we heard the early activation of recovery groups and associated planning was effective across North Queensland. All groups identified early the importance of rapid damage assessment for recovery planning. A common experience A challenge for all involved was the time Debbie took to cross the coast.

North Queensland

State-level operations

Central Queensland

South East Queensland

4.30am • “Approx. 4000-5000 guests/ staff on Hamilton Island, 430 guests/staff on Daydream Island and 607 guests/ staff/contractors on Hayman Island”taff/ contractors on Hayman Island” Morning (approx. 10.30am) • TC crossed over Whitsunday islands 12.40pm • TC Debbie made landfall Airlie Beach as a category 4 1.00pm • TC crossed over Proserpine as a category 3 From 3.00pm • BoM advised gale force winds to impact Ayr 10.00pm • TC crossed over Collinsville as a category 2 Bowen and Proserpine cyclone shelters transitioned to evacuation centres Early hours • System dissipated to a tropical low south west of Collinsville Townsville LDMG stood down Mackay airport reopened with restrictions 3.00pm • Whitsunday Pilotage Area reopened Commercial flights arranged from Hamilton Island to Cairns, Sydney and Bowen Whitsunday PCYC opened as evacuation centre pm • Navy evacuates 200 from Daydream Island to Airlie Beach 5.00pm • Police assist evacuation flights on Hamilton Island 9.30pm • Last 100 evacuees from Daydream Island move from Airlie Beach to Townsville Late evening • Private charter takes Hayman Island guests to Sydney via Hamilton Island

28 March

29 March

30 March

31 March Burdekin LDMG stood down 3 April

Whitsunday LDMG transitioned to recovery

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4 THE THREE CONCURRENT EVENTS

North Queensland: Whitsunday • Mackay • Isaac