Good morning from the Left Coast...
CHP and CAL FIRE have dispatch centers scattered around the state; they use the city or community name the center is located in, with the only exceptions I can think of being "Golden Gate" for the Bay area CHP, and "Border" for the San Diego area CHP centers.
Local government agencies, both police and fire, vary from one end of the spectrum to the other. There are various versions of "Dispatch", "Control", "SO", "Fire Dispatch", etc. Many use geographic references; ie. Placer County Fire and SO is "Placer"; Nevada County SO is "Nevada County".
A couple that stand out in my memory is "Main" for some Sacramento area PD's and Sac SO (before they went to trunking; now they just use the officer ID) and "Allessandro" for Riverside County Sheriff back in the day, because their center was located on Allessandro Road in western Riverside County. Haven't heard them in years, so I don't know if they are still using that.
When they were still on analog VHF, San Bernardino SO used the geographic location of their dispatch centers (Barstow, Victorville, Morongo (for the Morongo Basin), except for their Metro area dispatch, which was "Control". When they went 800 trunked in the early 90's, they consolidated to two dispatch centers, and began just using the deputy's callsign...however, you would occasionally "Control" or "Victorville" being used, especially when they wouldn't answer the deputy after several tries.
If I would have to hazard a guess, I imagine a significant number of agencies use some form of geographic or location-based reference.