Survivors of a devastating 2009 bushfire in Australia won final court approval Tuesday for a nearly Aus$500 million (US$407 million) payout -- the biggest class action settlement in the nation's history.

The Kilmore East blaze was the largest of the "Black Saturday" February 2009 fires in southern Victoria state that left 173 dead and razed more than 2,000 homes, the nation's worst natural disaster of modern times.

Thousands of people joined an action blaming power company SP AusNet, which until January was majority-owned by Singapore Power, over the Kilmore inferno, which killed 119 people and caused an estimated Aus$1 billion in damage.

Parties including SP AusNet agreed to a settlement of Aus$494.7 million earlier this year, with the power company making the biggest payout, but the agreement needed court approval, which was given Tuesday.

The other parties were Utility Services Corporation Limited, which was contracted by SP AusNet to maintain the power line, and the Victoria state government's Department of Sustainability and Environment for allegedly failing to reduce fuel loads.

Plaintiffs claimed SP AusNet's faulty equipment ignited the blaze. The company has previously said the settlement was reached without admission of liability.

Lead plaintiff Carol Matthews, whose son Sam, 22, burned to death, said the judgment provided a huge relief for her and other survivors of the fire.

"It is a huge relief to know that the court has approved a settlement and that people will finally receive some compensation and justice for what we've all been through," she said.

"Nothing will ever replace what we have lost, but today we have been vindicated for standing up for our rights.

"Hopefully we've played an important role in ensuring large organisations adhere to higher standards in the interests of community safety," she added.

Class action lawyers Maurice Blackburn said the Supreme Court ruling rubber-stamped the sum of money and how it should be distributed.

Maurice Blackburn senior associate Rory Walsh said a settlement on such a scale had never been attempted before in Australia.

"Even with a team of assessors working tirelessly in evaluating claims as quickly as possible in order to get the approved compensation to people, the court has recognised that we will need to fully process around 30 claims per day for 18 months," he said.

The claims were mostly for personal injury and uninsured and underinsured property loss with the payout more than double the previous highest Australian class action settlement of Aus$200 million.