Chestermere appears to be the fastest growing town in Canada, growing by 148% since 2001 to 9564.
Milton, Ontario grew by 71.4% to 53,939, however it is still classified as a town, so it would appear that Airdrie is technically the fastest growing city, up 41.8% to 28,927.
Calgary grew just over 12% to 988k.
Okotoks grew by 46.7% to 17,145. Cochrane up only 14.3% to 13,760. Strathmore up 34% to 10,225.
Grande Prairie is nearly 50,000 people now. Red Deer over 80,000.
http://www12.statcan.ca/english/census/index.cfm