Claus's article, linked to below, discusses the possibility that 5.9 GHz will be opened up for Wi-Fi.
Dedicated Short-Range Communications (DSRC) is a technology promoted by the Department of Transportation (DoT), but which has never been used much since its inception in 1999. It uses a 75 MHz span in that band. So far there are only a couple thousand devices that use it, compared to the millions of Wi-Fi devices out there.
I'm sure the DoT will raise a stink, if they are asked to vacate it.
Here is a copy of the original FCC announcement in 1999 about it:
DSRC is IEEE Standard 802.11p. I don't know CWNP policy on posting reference links here.
Like all 802.11 technologies, transportation for one (V2V and V2I) do not see DSRC as the correct solution for mission-critical operations focused on safety and reliability. 802.11 technologies are based on CSMA/CA.
Safety and reliability mission/business-critical operations rely on guaranteed QoS. Reason why light rail and railroad rolling stocks worldwide do not use 802.11 technologies on their V2I and V2V infrastructure.
I do have an IEEE WCP as well as CWNP, along with FE/EIT.