OP, it's easy to find dog friendly places on AirBnb or VRBO.
We have stayed with pets on the Shenandoah river... Example:
https://www.airbnb.com/rooms/19909471?source_impression_id=p3_1738849809_P3ShQFSmll39tP9Q
And a place at Saint Michaels on the water with its own pool. And at Lake Ana (we didn't go into the water but rented a boat for a few days, and went fishing etc).
Tons of options.