ive had some good times with waterfall bongs... One time I was at my buddys house who lives in this little neighborhood. We had some weed and decided to toke so we made a waterfall bong (since my piece was at home and he didnt own one). Well we filled a bucket up with water lol and were walking around the neighborhood with a bucket of water and a sobe bottle at night (sketchy much?) and he took me to a place where he usually tokes in the woods on these peoples second driveway on the corner of a 3-way intersection. So we are just sitting there ripping waterfall and a car is coming so we dive into the woods (and my friend whos smart and turned his cell on silent couldnt find it for 10 mins). When we are clear we start ripping again and we can still see the car down the road aways but its all good. Well we were chilling there keepingg an eye on the car and noticed what we hadnt before, the only reason we could still see it was because it was stopped then all of a sudden it went into reverse and started coming our way. So we hid the bucket and we (again) dove into the woods. The car stopped in front of the driveway we were in and scanned it looking for us but didnt see nething so finally moved on. It went and stopped at the same spot it had before so me and my buddy went on a long treck through lots of woods back to his house a few blocks away. We went and we hid behind his pool house and finished ripping there. Once we were done we just dumpped the bucket and snuck back in the house and chillaxed! it was pretty sweet and the adreniline rush we got from those people bothering us was awesome lol.

EDIT: Btw we had the bucket of water because no sink was available so we would just fill up the sobe with water when it was time for the next hit and then let the water flow out into the bucket.