According to Deadline, producers have been in the process of casting other roles for "Flint," but the film is still on track to begin production in Toronto next month.
The film is based on Time magazine's February 2016 cover story by Josh Sanburn titled, "The Toxic Tap."
Cher’s role was a Flint resident whose family was impacted by the crisis.
"Flint" is described as "a hard-hitting, fact-based drama that will explore the events that led to the toxic crime and shed light on politics of the poor management and the human element of residents who suffered and were ignored," according to Variety magazine.
Katie Couric will also serve as an executive producer for the Sony TV-produced film.
This week, comedian Amy Schumer announced she will no longer star in another Sony-produced film as previously planned.
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