Building a pond/waterbox out of wood

[WillyJohan]

I wondering if folks had any thoughts about the best way to build a larger water box/above ground pond (say 10' x 15' x 4') out of wood. Ive got about 50 gpm of water flowing that I'd like to route into the box for various purposes. The box walls would be above ground and the whole thing would be sitting logs to elevate the floor. I don't want to use any liner material and don't mind if it leaks a bit (as long as the leakage rate is less than 50gpm).

Are there any construction techniques that might work for this? 

My original thought was to build full scribe log walls using wood from the property, perhaps adding some sort of gasket material between the logs and stitching the logs together every couple of feet (either with cable bands around the whole wall or deeply countersunk GRK structural screws applied between each subsequent layer) to hold everything tight.

My other thought was to mill some of the large cotton woods that I need to take down anyway into 3" or 4" thick boards and stack them, again with some sort of gasket materiel between the butt joints and vertical strapping every couple feet to keep everything in place.

Would either of these actually hold water if executed properly?

my concerns for the first approach is that it's almost certainty beyond my skills to scribe the logs well enough to achieve a reasonable level of water tightness (though there is a local who could do it for me, if cost was no concern). I also don't have many big trees on the property and i'd rather not cut them down for this silly project. Assuming I was using 8 to 10" logs (likely larch or hemlock, but open to suggestions) how long might such a box lost when filled with water for 5 months out of the year.

For cotton wood, my concerns are about longevity and stability, anyone have a guess as to how long it would take for 3"+ cotton wood boards to rot out if on side were submerged in water for the summer months?

I'm also interested to hear any other ideas about building techniques that might work better.

thanks in advance.

[JJ]

I think a wooden water pool will be pretty water tight once full for few days from the wood swelling.  Maybe make round with vertical boards and metal band on outside.  Many water tank reservoirs and above ground pools were made this way. 

    JJ

[JJ]

Don’t think log construction will work at all at all or for long; what do I know ??

Al above ground pools are not that expensive, like a 1% of what a new pickup truck cost. 

  JJ 

[beenthere]

As JJ says, wood barrels and large tanks have been made for years. Think oak whisky barrels, for one.

Wood boats/sips for another application of wood holding water... just don't let them dry out. 

[Don P]

There is a router bit set for making hot tubs, it makes a convex rounded edge on one edge of a board and then the matching bit makes a concave edge on the other side. There are basically silo rod kits for wrapping around them. I don't know what old silo rod was but it seemed to be really good ductile steel. I've unfolded it out of a farm scrap pile, beat it straight and tied their barn back together with it.

[WillyJohan]

Thanks all for your thoughts.

my concern with going with the vertical stave approach was just the size of the thing, I've seen loads of plans for smaller wood fired hot tubs and what not but never anything particularly large and i was thinking that corralling all those staves into a circle would be a pain. but, now that i think about it, i guess with a larger diameter, my staves could also be wider, so maybe it is a non-issue.

As to above ground pools, unfortunately aesthetics are are going to out weigh cost in this case (within reason), this will be combination a fire protection water drafting source/swimming hole for an off gird camping resort in the mountains and it will be pretty central so we need it to match the overall rustic of the rest of the development.

Anyone have thoughts on using cottonwood? the 42 year old rafters in my house are 2" x 15" rough cut cottonwood and when we recently did some repairs they were in great shape even though the roof has been leaking for years. The lack of splinters and low cost are added benefits. I don't mind if the thing falls apart in a few years if was cheap and easy, but I'd prefer to get 5 or more.

-W


PS for the log approach, I was inspired by one of my favourite places, Burgdorf Hot Springs in Idaho, their pool is made of logs and has been more of less unchanged (other than being discovered by hordes of tourists) in the 40 plus years I've been going, but I'm guessing the whole thing is below the water table so leakage is likely not really an issue:

[beenthere]

All things considered, cottonwood should work just fine for you.

Keep in mind that the upper logs need to be either in water or nearly so. Or plan to replace the upper logs more often. Nice looking log pond in the photo. 

[Chilterns]

Venice is built on larch piles and larch is also used as fishing boat skin planks to keep water out !

Alder wood piles were used for building crannogs in Scotland / Ireland. Alder is normally considered to be perishable but when fully submersed in water it has a proven life expectancy of thousands of years.

Oak & elm are employed in water mill wheels where although not all ways fully submerged have a good long life when operated regularly i.e. constant wetting.

Oak was used for Roman riverside revetment work in London where fully submerged has lasted thousands of years also Henry VIII's Mary Rose built of oak was recovered after 500 years from the Solent.

The timber of choice for canal lock gates is Greenheart (from Guyana) however oak and elm are also used.

The key to long life would appear to be keep wet and exclude oxygen.