There are very few digital frequencies in Salt Lake. One or two Narc frequencies and that's about it.
All the police, fire, medical etc are on Motorola Smartzone. There are 2 systems in the Salt Lake Valley. There is the Salt Lake City system, which includes SLC police, fire and a few county police frequencies. Then there is the UCAN system which is highway patrol and out-lying metro police forces. UCAN also covers most of northern Utah. It's all in the DB here on the site.
Most of northern Utah has gone to Motorola Trunking, but pure digital is sparse here. A digitial capable scanner doesn't get you much.