The announcement is being made today at the launch of the program for the State Government’s “Open State”, a 10-day collection of events from October 18-27 that will include the festival.

Festival of Ideas founder and chairman Greg Mackie said the popularity of the Oscar-winning film Erin Brockovich had made the woman after whom it was named “one of the best-known citizen activist voices in the world”.

“She worked with the system and achieved a spectacular win for public accountability and the environment,” he told InDaily.

“She has an excellent reputation [as a public speaker] and we can promise the audience an in-depth experience.”

While working as a law clerk in California in the 1990s, Brockovich carried out an investigation into claims that the Pacific Gas and Electric company had been poisoning a town’s ground water for more than 30 years – leading to a record court settlement of $333 million in damages to 600 residents.

Since Roberts’ portrayal of her in the film dramatisation, she has published several books, hosted television programs, championed numerous other causes and become president of Brockovich Research & Consulting.

Mackie said Brockovich’s appearance at the Festival of Ideas would be “a significant national moment”.

She has visited Australia previously to speak about environment issues and has also been involved in several cases in this country. She reportedly recently replied to a letter from a resident affected by Adelaide’s Clovelly Park soil contamination controversy saying she would be happy to lend her name to their fight for compensation.

Although it is not known what issues Brockovich might discuss in Adelaide, Mackie said: “With the 2016 Festival of Ideas being plumb in the middle of Open State, the opportunity to draw inspiration from somebody who has not only talked the talk but walked the walk is relevant to a whole range of public interest issues.”

The Adelaide Festival of Ideas was held every two years from 1999, and was due to be run this spring before it lost its government funding. However, Mackie and other supporters resurrected the event, with InDaily as media partner, after establishing a not-for-profit organisation to oversee it. In March, it was announced that the re-booted festival would partner with Open State.

Open State will feature more than 50 separate events covering topics such as smart cities, entrepreneurship, the new economy and engagement, setting out to explore “how enterprise and innovative leadership can address the complex challenges of the future”.

Further speakers for the Festival of Ideas will be announced in the coming weeks, with the full program to be released mid-September.