When I lived in Michigan, WEMU was a public radio station that primarily played jazz on weekdays and blues and R&B on weekends. Looking at their schedule, it looks like that's still pretty much what they do.
The greater Detroit area was at one time a phenomenal place for jazz on the radio, with multiple 24-hour jazz stations playing all possible jazz genres from all eras, but it's been slowly losing that local character for a while now. If there was going to be anywhere in the country where an all-blues station could make a go of it, Detroit would be a prime candidate, and as far as I know it never happened.
The greater Detroit area was at one time a phenomenal place for jazz on the radio, with multiple 24-hour jazz stations playing all possible jazz genres from all eras, but it's been slowly losing that local character for a while now. If there was going to be anywhere in the country where an all-blues station could make a go of it, Detroit would be a prime candidate, and as far as I know it never happened.