I know this is old but thought I'd comment anyway.
There's a new SC going in Rehoboth but has not started construction yet AFAIK:
Rehoboth Beach, DE | Tesla
Also, there is one just to the East of the Bay Bridge (Queenstown, MD) now which is under construction and looks like it's almost done:
Future Queenstown MD Supercharger moved to Grasonville.
When we were in Rehoboth this July, both city-provided chargers were broken. Very frustrating! I charged from 110v whenever my car was not in use (which was most of the time) and was able to get up to 100% before the trip home. Also, if you're there, check PlugShare because there is a nice guy who lives just off of Rehoboth Ave. who offers his charger to those in need.