District 4 is adding location markers to the MacArthur Maze (I-80/I-580/I-880). They are white letters on a blue background painted on the bridge railings. Each ramp in the interchange has a letter prefix. The East 80 to East 80/West 580 ramp is "A". The markers are posted every 100 feet and increase sequentially -- A1, A2, etc.
In the last few days they've started to add signs to areas where there are no concrete barriers. These signs also have white letters on a blue background. They remind me of a simplified version of the driver location signs (https://en.wikipedia.org/wiki/Driver_location_sign#Driver_location_signs) used in the UK.
Along with the enhanced mile markers on Highway 17 (https://www.aaroads.com/forum/index.php?topic=27944.0) it seems like District 4 is trying out new ways for drivers report their locations.
Does anyone know anything about this project?