Calgary Mayor Jeromy Farkas says there's a "ticking time bomb" under the city's streets, and that means a new reality for residents moving forward.

"This Bearspaw feeder main served Calgarians for many years, but right now, it is at end-of-life," Farkas told CBC Radio's Calgary Eyeopener on Monday.

"No amount of short-term fixes, no amount of patchwork will be able to get this back into a reliable condition."

Last Tuesday, Calgary saw its second "catastrophic" water main break in the northwest in less than two years. That led to water restrictions and a boil-water advisory for several northwest communities, which were lifted late on Sunday.