He said the process for the film began three or four years ago when he started following certain people and their outcomes.
"We had about 600 hours of footage to fit into 90 minutes. We chose the story of the central city, how do you rebuild a central city, the changing nature of a central city. We made that the story really."
Smythe said the central government stepped in after the quake and decided to rebuild the city in a certain way.
"Unfortunately that happened at a time when the nature of city centers was changing.
"Because of the malls, we no longer go to the city like we used to. It's no longer a CBD, it's a place where people can live."
He does not think the story is over yet, Smythe said.
"I reckon it's half time, I reckon it's time for us to take stock and for the people, the little guys, to come in.
"We can get back to having a buzzing city."
• To find out more about the documentary go to www.facebook.com/whenacityrises/