Originally the setting Cameron is standing was intended to be a mountain cliff edge. But upon review the slope of the mountain didnt look threatening enough. It was during post-production the shots of the dam were taken and actors added in.
The film was entirely shot on the Mount Ainslie lookout in Canberra, except for the few shots of the dam.
Colin Giles, who plays The Director, is known as a talented comedic improviser on sets. However he has said he was anxious to get his lines word perfect during his scenes as he enjoyed the written dialogue so much, particularly his monologue.