Hi there allygurl,
Above ground ponds are very tricky in that you not only have to make them look nice but you also have to keep them standing. Water weighs around 8 lbs a gallon. Once you stack water up (fill a raised pond) the pressure starts to build. Railroad ties although heavy may not have enough strength to hold back that kind of weight over the long term. You may want to consider using stone and mortar or layering your walls with the ties on the outside and a bit of cement footings or cinder blocks with motor on the inside. I guess it all depends how long you want the pond to be around. I hope this helps. If you get anything out of this reply remember this. Digging a hole in the ground and filling it with water is easy. Making water stay above ground level makes it harder.

joshthepondguy-thanks for your reply. We will stack the corners and joints log cabin style, and drill through the whole thing inserting heavy duty rebar through them and into the ground.In addition, 4X4's will be added to the outside corners and along the sides every 4-6 feet. Then the top board will be secured on top of them and the ties. This should hold everything together,I hope!

I did the same thing, using 4x4's stacked on top of each other, and things have been fine. One note, though- the top board should NOT be treated, as the chemicals would leach into the pond and potentially cause problems. Use a naturally weatherproof wood, such as cedar or redwood, instead.

Here is a link that might be useful: My pond

kponder-beautiful!! That's exactaly what I want! Hubby went and bought the ties, but some were in really bad shape. He took them back. Lowe's was not too pleased with him either! He told them if he could pick the ones he wanted, he'd take them, but they refused to let him in the lumberyard. They were advertised as retaining wall grade, but who wants to build a retaining wall with ties that have large caverns in them? Anyway-I guess we'll have to go 4X4's or 6X6's. If not, my pond dream will once again come to a screaching halt. Thanks for the tip about the top board,had not even thought of that! How deep is your pond?

I like kponder's pond, too.
I am amazed that Lowe's was so difficult. I have been in lumber yards including Lowe's in many states and I was always able to pick out my own materials. In fact just to get the stuff, I had to drive into the yard to where it was stacked and where I was met by an employee. I could always reject bad pieces. Sandy

allygurl-
My pond is 1 1/2 feet above ground and 1 foot below ground, so 2 1/2 ft altogether. I dug down before placing the 4x4's. As long as the 4x4's are securely bolted together at the corners and a couple places in between, they should be plenty strong enough to hold the water. Just make sure your frame is good and level, and the corners are strongly supported underneath by some concrete or at least large bricks (buried in the ground). I think that because of the weight of the half barrel waterfall, one end of the pond has sunk a little- not enough for anyone but me to notice, but still...Then just lay your liner, fill with water, fasten your top plank over the liner where it comes up over the 4x4's, then trim the liner on the underside of the top plank. I'm thinking about adding vertical strips of cedar over the 4x4 sides, to dress it up a bit, or even some brickwork to match my firepit.

Here is a link that might be useful: Firepit

Hi
Have run a 5x10 x3 foot deep pool made of stacked 4x4's
since 1982, 18 inches above ground and 18 below. I even used a fiberglass tarp rather than a liner as the original purpose was a place to collect rainwater but evolved into a garden pool over time. Last year I relined not because it was leaking but because it had become overrun with marshmallow and strangler figs lol.
Used that opportunity to add a 2x6 foot piece of glass to one side as well as an overflow. Only problem has been that the cap has rotted no matter what material I've used. Went with vinyl fencing to which I was going to add a faux finish as well as tile to the sides but have yet to get around to it.
Jury is still out on the glass side .have had no problems with leaks but it faces west, is really too low for good viewing and the plants block that anyway.lol Have yet to come up with a way to clean the glass.
Was surprised at the lack of rot in the 4x4's even those below ground. it had settled at one corner but just leveled it again. I think it's good for another 25 years but not sure I am .lol gary

Thanks for the replies. Looks like 4x4's is the way we will go!I live near the coast,(about 25-30 miles) outside of Charleston,S.C.,and didn't want to go too deep all over. Was thinking of going about a foot down on one end, and about 18"-20" tall. Freezing won't be an issue. I shouldn't say that with all the crazy weather we've had in the last several years! Anyway, normally, it wouldn't be a problem.Like I said, I want to be able to work it with as much ease as possible, due to limited mobility.Thanks again and happy ponding!