MileCheckHow do dispatchers find the highway mile marker for a caller's location?
They match the caller's GPS position against a map layer of mile markers. A 911 center usually has its own county or state layer. Towing, roadside assistance and fleet dispatch teams that work across states need markers for every state, which is what the MileCheck API and dataset provide.
Two ways a location comes in
- The caller reads a sign. "Eastbound I-90, mile 52." This works when the driver can see a marker and knows the direction.
- The phone or truck sends coordinates. A wireless 911 call usually arrives with an estimated location from the phone, and fleet trucks report GPS from their telematics unit. Coordinates have to be turned into a highway and mile before a tow driver or crew can use them.
What dispatch centers use today
- 911 centers load a mile marker layer into their dispatch map. Counties often keep their own, such as Roanoke County's layer for I-81. These layers usually stop at the county or state line.
- Towing dispatch software such as Towbook lets a dispatcher enter a highway and mile marker to place a call on the map.
- Roadside programs and fleets that cover many states have to stitch together a layer for every state, or buy one.
Where MileCheck fits
- The API turns a GPS point into the nearest route, mile marker and direction in all 50 states, one call at a time.
- The dataset loads every marker into your own dispatch map or system, so lookups work without a network call.
- Both come from state DOT data. Marker positions are approximate. Some states survey each sign and others place points along the route line at each mile.
MileCheck is not a 911 service and does not dispatch help. Drivers who need help should call 911.
Questions people ask
Does a 911 call include the caller's mile marker?
No. A wireless 911 call usually carries an estimated location from the phone. The dispatch map turns that into a road and nearest mile marker if it has a mile marker layer loaded.
Why do mile marker layers stop at the county line?
Counties and states each keep their own GIS data for their own area. A team that dispatches across many counties or states needs data that covers all of them.
Can a towing or roadside company use the MileCheck data?
Yes. The API returns the nearest marker for a GPS point, and the yearly dataset license covers showing markers in your own dispatch tools.