Crazy question #1 - building the rectangle

[Jimmy Gibson]

I'm 60. Figure I can make pond walls out of paper towel tubes and probably be OK.

Seriously though, more than a few times I've just dry stacked block, once bales of straw, and I've used billboard plastic and thin hardware store plastic as liner for a temp pond. I agree, build for what you need. But, imo, people researching should be given the limitations and standard methods so they can choose.

But also think about the lay of the land..... Flowing water is a powerful thing..... Not everyone has a good flat peice of ground..... But they can still have a pond

 

[Alisonvalley]

Believe it or not, I'm making progress ... putting my thoughts together to post soon. And to talk to a construction crew on Friday Cost is a consideration, but so is my going-on-60-year-old back!
In the meantime, thanks all -- you're giving me good food for thought. CeeJayH, I love your pond -- it's a simple design, elegant, naturalistic. Sissy, husband and I made our first ever visit to Springdale last week! They're still getting set up for the season. Looks like a good source to buy a water lily, when the time is right.

 

[CeeJayH]

Cost is a consideration, but so is my going-on-60-year-old back!
In the meantime, thanks all -- you're giving me good food for thought. CeeJayH, I love your pond -- it's a simple design, elegant, naturalistic. Sissy, husband and I made our first ever visit to Springdale last week! They're still getting set up for the season. Looks like a good source to buy a water lily, when the time is right.

My back was one reason why I decided on a raised pond. I deliberately built the wall at the patio end a full 9" wide, and topped it with slate so it's possible to sit on it. It means we can get close to the fish without having to get down to ground level.

Thanks for your kind comments regarding my pond. I must post recent pics, it's naturalised very well,

 

[sissy]

My pond is half below and about half above ground on 3 sides since t is built into a slope .I just used concrete block with my heavy clay soil packed in them with some rebar .Then I built and outside wall of retaining wall block

 

[Waterbug]

With curved and roundish ponds stress is more evenly distributed around the pond so there is less risk skipping the rebar. But in 90 degree corners the entire length of a wall pushes out focusing a lot of stress in the corners.

Took me awhile to find this pic...

This pic is a rectangular pond I think it was something like 4' above ground level. This was posted in another forum years ago by a very brave person. Most people don't like to admit failure or listen to dozens of "experts" say "I told you so". We learn better from failure.

This pond failed pretty fast as I remember, first few weeks. What's impressive is it didn't completely fail.

The builder knew to use rebar and did...but not in the corners. That's where it's most important and important to be done correctly. The builder also didn't use bond beam block or fill the block with concrete.

For most DIYers setting block with mortar joints is scary and difficult. It's a skill. But block can be simply dry stacked and then filled with concrete. Very little skill is required. Mortared joints add very little strength. They were first used to keep courses level because manufactured blocks weren't very uniform like they are today. And it uses less material but only when structure doesn't require certain stresses.

The pond was fixed by adding buttress walls and also a lot of steel was strapped around the outside to hold it all together. Probably about the same cost as ripping it down and starting over.

 

[Alisonvalley]

The latest version! for strength purposes the front of the rectangle has been curved. We're planning on using Diamond Pro" block -- 75 pounds, hollow core. The back straight wall I think could be CMU's, bond beam with rebar especially on the top course. Question: Given that pond enclosure is buried on three sides by soil, do I need to tie the back wall to the block wall, or will ground pressure keep it tight enough? I'd add two cinderblock units (at the question marks in the drawing) to help keep the side walls from bowing out.

getting closer to a pond that will make me happy, and have a chance of lasting a good long time... comments welcome...

 

[sissy]

main reason I did a block wall outside of my block wall .Plus I could Insulate between the 2 walls

 

[Waterbug]

Assuming you're going to concrete fill the hollow core what I would do is cut the ribs down a bit so you can lay a horizontal strand of rebar. Where the ?? are the rebar is bent and goes into the bond beam block. You want like at least 3' of continuous rebar in each wall. It should overlap the other rebar by like 20" and tied together with proper rebar wire. Cheap enough and easy to work with.

Because you'd just be cutting into the block enough to get the rebar in I'd cover the rebar where it cross block surface with anchor cement. Should help stop rust and it's pretty cheap. I'd fill the course hollow with concrete, set the rebar and then fill the joint where rebar crosses block so the filled concrete blocks the anchor cement from running out. You want to smooth the top fast as the anchor cement is very hard and sets very fast, so the next course can go on. The rebar course should have at least one course above it.

If you run horizontal rebar all the way round a course you will have very good insurance. Two courses and it should last 100 years. Your call.

The block deal where you have the ?? is called a buttress wall if you wanted to research more. Without horizontal rebar it wouldn't help much. It would only hold that one vertical column of block. Once we're talking rebar you can just tie into that back wall and you're done.

Ground offers so little outward resistance I would not even consider it. Horizontal rebar is the best option...not to say it's 100% required.