Victims of south-east Queensland’s 2011 floods have finally won a partial, $440 million payout a decade after the negligent operation of two dams saw thousands of homes and businesses swamped.

The Queensland government and state-owned dam operator SunWater have agreed to the payout, which is about half of what’s owed to more than 6500 class action members.

But there’s been no settlement with the other dam operator, state-owned Seqwater.

Class action law firm Maurice Blackburn said Seqwater would continue to appeal the NSW Supreme Court’s 2019 decision that it failed to operate the dams properly, or take into account rainfall forecasts when releasing water.

Principal Rebecca Gilsenan said flood victims had endured a long and arduous legal battle that was not partially resolved.

“We hope [it] will bring some much-needed closure to our clients, who have had to endure significant uncertainty and frustration while the defendants fought this case at every turn,” Ms Gilsenan said on Friday.

“Of course, complete closure can only happen for our clients when Seqwater also settles, or Seqwater’s appeal is finalised.

“The class will continue to vigorously fight Seqwater’s appeal, buoyed by today’s substantial settlement reached with the other two defendants.”

The settlement is subject to approval by the NSW Supreme Court and agreement on terms, with an approval hearing likely to happen before Seqwater’s appeal starts in May.

The case was heard in a NSW court because it was initiated before class actions were allowed in Queensland in 2017.

-AAP