For the purpose of responding to calls for service, the City of Bay City has been divided into four geographical areas called districts. Districts are divided by the Saginaw River into east and west sides.

The east side includes Districts 1 and 2. District 1 (blue) is the northeast side of Bay City from Woodside Avenue to Columbus Avenue. It incorporates Downtown Bay City and Center Avenue all the way to Essexville. District 2 (red) is east of the river from Columbus Avenue to McGraw Street.   

The west side is divided into Districts 4 and 5. Euclid Avenue is the dividing road between the city limit and the county.  District 4 (orange) is everything north of North Union Street.  District 4 (green) is everything south of North Union Street.