don't know i have only fished on the potomac one time and that was last fall me a nd 2 friends went down for a full day of bass and what ever else we caught .
we went to four locks or big pool ( might be the same place )
but am for sure going to be back this summer with the family most likly for a weekend trip fishing and camping .
have never fished below that area but hear there are saome monster cats and such further south i think down where you are talking about ( d.c. area )

Scott