"We have been conscious that we want a memorial in a location that can be meaningful for all those who were affected by the tragedy rather than placing any emphasis on any particular site where lives were lost."
Mayor Lianne Dalziel said February 22 had had an "immeasurable impact" on the people of Christchurch and affected people throughout the world.
"Choosing a site for the memorial is a significant step forward to having a dedicated special place where people can come and reflect and remember all those we lost, and everything that people everywhere have been through on that day, and since."
Mr Solomon said the Avon River was an appropriate place for the people of Canterbury, having been a meeting place for centuries.
The Government has set aside up to $10 million for the project, to be combined with $1 million from the Mayoral Relief Fund.
The shape of the memorial will be decided through a three-stage open design process, the first stage which was launched today.
'Ideas to Remember' asks people to submit their own ideas for the memorial and is open to anyone anywhere in the world.
The second stage will narrow the submissions to six, one of which will be chosen as the design.