"Single Drop"

With the COVID virus my wife cancelled all our camping reservations over the summer months. We couldn't travel during those times. So I don't know the specific camp site, but I suspect it was in the Canada area if that helps. All I could think is it was a just a single hook up, i.e. one site. But don't know why they needed to say that. I thought I was the newbie and everyone else would know. Surprised no one else had bumped into this previously, but thanks anyhow ....