I through DTE went through Consumer's Trunk System?
http://www.radioreference.com/apps/db/?sid=1579
You will see Northville which is in Wayne county. I know they do this in Kent county in the G.R. area.
From the list:
Metro Detroit Gas Talkgroups
DEC AFS Mode Description Tag
2002 15-102 A Livingston County Gas Operations Utilities
2003 15-103 A SW Oakland County / NE Washtenaw County Gas Operations Utilities
2005 15-105 A Unit-to-Unit Utilities
2007 15-107 A Wayne County Gas Operations Utilities
2008 15-110 A E. Oakland County Gas Crews Utilities
2009 15-111 A Oakland County Gas Crews Utilities
2010 15-112 A Macomb County Utilities
2011 15-113 A Macomb County Gas Operations Utilities