The original run was for 6 years on CTV---and the show has been off the air for at least 2 or 3 years now.
Probably the most successful recent Canadian program on one of their commercial networks. Look for spinoffs that may be playing on CTV 2, such as Dan for Mayor and Hiccups, which feature some of the Corner Gas cast.
Brent Butt and Nancy Robertson are married to each other in real life.
If you are new to Canadian TV, you might want to also check out AMI on the C-band side of ANIK F1R for Murdoch Mysteries (captioned audio overlaid onto the program). It's playing its final commercial season on the CITY-TV network, which you can find on the C-band side of 111 West (SCN, in the evenings. Murdoch is getting picked up by CBC next season. AMI also has classic Canadian series such as North of 60, DaVinci's Inquest, and even reruns of the Rockford Files. Little known fact: the actor that played Angel on Rockford Files is a well-known Canadian actor that has since played on a number of Canadian series, in addition to work in Hollywood.