Queensland water authorities found negligient in 2011 flood victims class action

New South Wales Supreme Court Justice Robert Beech-Jones found that the Queensland government, Seqwater and SunWater were negligent in their conduct during the flooding that came when rain of "biblical proportions" fell around January 11, 2011.

The class action alleged that flood engineers were obliged to release water from Wivenhoe and Somerset Dams ahead of predicted heavy rainfall but failed to do so during the early days of January, exacerbating flooding that devastated homes and businesses near the Brisbane River, lower Bremer River and the lower part of Lockyer Creek.

In handing down the decision, Justice Beech-Jones said flood engineers ignored rainfall forecasts and did not follow procedures set out in the flood manual they had roles in creating.

Justice Beech-Jones said while there was potential for honest mistakes to have been made during the stress and exhaustion of flood operations, the engineers' failings did not concern heat of the moment decisions.

"Instead, they derive from a failure of approach, specifically a failure to follow the very manual that they had drafted or participated in drafting almost 18 months previously," he said.

He said the engineers "never determined the applicable flood strategy in the manual based on a predicted reservoir level (much less a predicted reservoir level that utilised a rainfall forecast), never determined to release water because rainfall was forecast to fall in catchments above the dams, never determined a volume of water to be evacuated based on a rainfall forecast, never determined to increase releases because of a concern that forecast rain might fall downstream at a later time and impede releases at that time and did not undertake any modelling that used forecast rainfall as the basis for flood operations".

"In substance, the flood engineers' actions were, at best, only determined by rain on the ground assessments.

"In particular, the amount of water they determined to evacuate was always only based on a rain on the ground assessment which was directed to a planning horizon of no more than 12 to 15 hours ahead.

"That period was far too short having regard to both dams' capacity and the catchment flow times above and below the dams."

The court heard that flood operations had ceased on January 2 and while another flood event was declared on the morning of January 6, releases did not start until the afternoon of January 7.

During that week both dams were above their full supply levels, substantial rain was predicted and significant rainfalls started on January 5.

"The failure to commence releases earlier was an instance of the flood engineers subverting the priorities of the manual by seeking to avoid the inconvenience occasioned by bridge closures at the expense of guarding against the risk of urban inundation," Justice Beech-Jones said.

He added that even after releases started, up until midnight on January 10, the flood engineers prioritised keeping bridges open.

"By that time, the amount of rain that had fallen, the prevailing rainfall forecasts and the reservoir levels pointed to the virtual certainty that flooding of urban areas would occur," he said.

While the flood victims won their negligence case, cases of trespass and nuisance failed.

The next stage of proceedings has been stood over until February 2020.