Funny, I was just talking about this with a bud at the office... My father-in-laws old boat house was on those along with the big foam blocks. He donated it to the local police and built a pier style boathouse. I plan on building a 12x12 floating pier on the pond. I can, I've been told get the barrels from the local cola plant... for $8+\- . I still need to figure out how many to buy to support the wait of the dock(wet) and a few bodies.... was thinkin I'd start with 8 or 10 ... one at each corner and the others dispursed as even as possible.
The biggeast problem I see is if one pops and having to drag the thing out to replace or add a barrel if I guessed wrong on the count....
The methode used to be fairly popular around here a few years ago but now every one has seemed to have gone to foam blocks....