Sorry I'm a little late to this thread...
VMRC patrols all tidal waters (salt water) in the state and the Potomac River, not just the Chesapeake Bay as was mentioned earlier. They typically transmit in the clear. The James, Mattaponi, and York are right in the thick of it.
About three-ish years ago DWR and DCR (State Park Police) partnered to have a single, centralized dispatch center. With that change, if I remember correctly, both agencies aligned and reallocated some of their talkgroups, which I don't think has ever been reflected accurately in the RR 'STARS' database page. With the co-dispatch, both agencies also upgraded to a singular CAD system, which from what I understand, is robust enough that many calls are dispatched and handled via CAD, and not over the radio.