A class action representing 6,800 group members has been successful in its claim against the Queensland Government, Seqwater, and Sunwater, relating to their management of floodwaters from the 2011 Queensland Floods.

The lead plaintiff is a sporting goods store that was flooded when the shopping centre it was located in became inundated with floodwaters from the Brisbane River.

The plaintiff alleged that the defendants' engineers had negligently managed the Wivenhoe and Somerset Dams during an extended period of heavy rainfall, as dam engineers prioritised keeping downstream bridges rather than avoiding urban flooding, and had failed to factor in extraordinary rainfall forecasts in deciding how to respond to the flood event. The Court ultimately found that the defendants had breached their duty of care, causing the plaintiff to incur losses.

Some scientists believe the heavy rainfall was exacerbated by a combination of the 'La Nina' weather system and climate change (read more about this here).

As climate change modelling predicts increased likelihood of extreme weather events, such as storms and floods, this provides a timely reminder to insurers, businesses, and government of the necessity to consider the potential impacts of climate change on their operational decisions and risk management. For example, infrastructure operators and businesses should ensure their plans of management include appropriate contingencies to manage the modelled extreme weather events, particularly if global temperature rises exceed 1.5oC.

Likewise, insurers can expect not only first party claims for property damage and business interruption during extreme weather, but also professional indemnity and third party claims relating to mismanagement of extreme weather risks or inadequately engineered infrastructure.

Almost 7,000 Queenslanders have won a class action over the state’s devastating 2011 floods, with a judge finding they were victims of negligence. ...

About 23,000 homes and businesses went under in Brisbane and Ipswich when authorities released huge amounts of water to protect the dams’ structural integrity. ...

Beech-Jones agreed with victims’ claims that engineers negligently managed the dams and that they did not factor in extraordinary rainfall forecasts in deciding how best to respond to the flood event.

https://www.theguardian.com/australia-news/2019/nov/29/thousands-queenslanders-win-class-action-dams-2011-floods