Queensland flood victims could miss out on $440 million in compensation after a massive court win for government-owned dam operator Seqwater.

Victims say a NSW Court of Appeal decision has let the prime offender responsible for exacerbating the 2011 floods off the hook.

They’ve already foreshadowed a High Court challenge, saying they’ve waited a decade for compensation so what’s a few more years.

The court has ruled in favour of Seqwater, which appealed a 2019 NSW Supreme Court decision that it failed almost 7000 Brisbane and Ipswich residents during the floods.

The 2019 decision found Seqwater, the Queensland government and another state-owned dam operator SunWater exacerbated flooding by failing to properly operate Wivenhoe and Somerset dams.

In all, about 23,000 homes and businesses went under after huge water releases to make sure the dams did not fail.

The Queensland government and SunWater accepted the 2019 ruling, and have agreed to pay $440 million to compensate victims.

But Seqwater vowed to appeal and won that battle on Wednesday.

If victims cannot overturn Wednesday’s ruling in the High Court, they will miss out on a further $440 million, Ipswich flood victim Paul Tully says.

“This decision defies common sense and logic given that SunWater and the state government have already accepted they were jointly liable for the flood,” he’s told reporters.

“We now have the bizarre situation where the state government and SunWater have agreed to pay $440 million as their assessed 50 per cent liability while Seqwater has squirmed out of its responsibility …”

He later said the only course of action was to go to the High Court.

“Who bloody cares now, it’s already been 10 years. Another couple of years won’t make a difference.”

Law firm Maurice Blackburn led the case, which was heard in NSW because at the time it began class actions weren’t allowed in Queensland.

The firm said it would carefully review Wednesday’s decision before deciding whether to launch a High Court appeal.

Mr Tully said he and other victims could take some comfort from a deal that guarantees them a share of $440 million from SunWater and the Queensland government.

“That’s unaffected. That money will flow next year, they can’t review that, and that can’t be appealed,” he said

-AAP