at this point it is the first i too have seen them though i heard about them. the area is still slowly coming out if the hibernation of the lockdown. most other images i see do not have running water though i like you feel it is intended.
the temp there when i walked to it was 95deg with a heat index of 106deg with inappropriately high humidity. that being said i did not spend that much time there. no details just yet on this scouting trip.
remember they originally referred to DC as the swamp because that was exactly what it was not just those who occupied it.
as a well known general once said "i shall return" just when its a little cooler
