Highway Call Boxes? 150.800mhz

[RayAir]

The VHF-HI band was open pretty good last night. I am located in Oakland County and was receiving a never heard before frequency. It sounded like it was from highway call boxes and had a computer voice talking. It went something like this:
150.800 mhz:
computer voice: " emergency call route 416......emergency call route 226.......... acknowledged by (persons name).........DCM has been powered up.........

Any ideas where this was coming from? I have never seen a call box on a highway in Michigan.

 

[gus88]

Does Ohio have them?
Northern Ohio was coming in the last coupleof nights.

Russ