Pond Project

[JacqG]

Hi everyone! Merry Christmas 😎

I created a trio pond project a few years back, had it looking wonderful with pond lining (many hundreds of dollars worth), was growing Lillies etc and it was all fabulous. But I had not reckoned on kangaroos jumping through the ponds at night; consequently the lining was ripped and useless! I am living rural on the south coast of NSW.

SO. I took the lining away and started researching what a "wilder" pond project would look like. I heard about Bentonite clay, read about it and reckoned it would work.

It didn't. The pond is clay so I do not know why the water eventually just ran away or underground or where ever it went!?

There are no large stones in the clay... can anyone assist?

I used  50.5 kilos of the stuff all over the empty dry pond...

What am I doing wrong? And is there another solution?

Thanks everyone (Pics are taking long to load...)

[Jewelleryrescue]

Hi @JacqG 

Have built a  100% water proof  pond that is UV stable and all but in destructable.

Can I ask how  deep is the pond?

What are the side walls made of?

Is there a concrete base currently?

50kg  clay sounds like a small area pond?    What are approx dimentions  Just say 1m x 1 m round or sqare etc it is just a mental pic for me.

The solution part 1.

I would concrete in the base of the pond for a solid base Thickness of concrete is depth dependant on water depth. 75mm to 150mm If kangaroos using it for a foot wash 75 min.

Then depending on the side materials  place a woven renforced mesh into the side wall cement floor join (inexpensive) and then paint a cement layer  mixed with silasec a remake of bondcrete that is totally water proof and sets harder the concrete itself.

This concrete  paint is is also  good  on water tanks with potable water.

I always thought it would add fire protection to timber too from embers  but not direct flames as painted timber would get heated through the concrete when thin.  I always  wanted to try that i you have wooden structures.

So this idea  is farm friendly and doable and cost effective.

Sound  like a  plan to you we  can  talk  more  details,

Plan B there is an Austrlian company that makes a polymere product that seals  whole earth ponds when it is sprinkled  ontop of the clay and earth.

A previously leaking /weaping pond acres  big will stop leaking through  hidden drain holes.   But kangaroo paws might disrupt  the base of the pond to leaking again.  Cement  wont.

[JacobZ]

Hi @JacqG,

I'm sorry to hear of the issues you're having with your pond.

There is almost certainly a gap in the clay that is allowing water to drain through it. Depending on the dimensions of the pond, 50kg of clay is probably not enough to create a thick enough layer to really seal the water in.

Unfortunately, this is outside of my expertise and is likely something you would need to speak with a pond builder about. 

Allow me to tag @Dave-1, @Nailbag and @Noyade to see if they have any advice they can offer.

Jacob

[Dave-1]

Afternoon @JacqG 

What a pain and have been there with ponds leaking as well.

I had an old style sandy concrete styled pond, it ended up have a few cracks in it due to age, things being dropped in it "kerplunk" and the water pipe for the house running an inch below the surface of the concrete....

I have given lots of thought to ponds leaking and what to do to stop it and how to as well. I want an outside stream that runs via solar but also can handle storm instances and absorb runnoff I have chosen that pond liner you have mentioned but I will line the lined with large rounded pebbles, What I loose in height of the water I will gain in longativity of the lining as less damage should happen to it. If you have pebbles down even if the kangaroos come on back fro a drink or two it should stand up better.

With the Clay, you need to have a solid wall of clay, think probarly 20cm thick for a pond at a minimun. 50kg wont really work. Other clays that people use for dams may be an option depending on where you live, the walls and base just need to be thicker.

Dave

[Nailbag]

Sorry @JacqG this is also outside my area of expertise. The only thing close enough that I have built was just a shallow 300mm moat style pond in the front of a house I once had. I used an additive to the concrete mix and then applied a rubberised sealant to the inside walls. There are quite a lot of newer products now available on the market since my build 10+ years ago.

Nailbag

 

[Jewelleryrescue]

Hi @JacqG 

Sorry  your pond cracked @Dave-1 alot of  people beginners at ponds under estimate the strength , water weight   and reinforcing required to have a pond not  crack.  This  includes me I had my learning curve too.   I  just built my biggest strongest pond  ever but  I still  needed to allow  water weight testing time before tiles added (Easier  to see and find fail  points, in exposed  new concrete.) 

 Your pond is concrete and totally  fixable  by the way I am sure those  cracks  can  be filled you may need some steel  in the base and another 50mm of cement followed by Silasec  and pure cement  paint. To try  reinforce possible weak points sight un seen.   Bondcretes can  be used into the admix to make  sure things  stay together . and would be good  between the  old pond base and the new.  Bondcrete is like aquadere in its  use but for cement.

Pro landscapers can  use  plastic pond shell and dig it into the ground is easest of  all.  I might have done this but my area needed a  custom built shape.

Pond liners yes Some pros  landscaper use them good for 5 years.  I have being there done that too.  Rarely will liners sit flat with out some sort of need to fold the  quality plastic liner on itself creating crease lines where i seams to crack and leak from first and totally fail  re 100% water proof  Maybe the ideal shape for a flat liner is a dish shaped dug out  ground pond with no corners and folds.

Swimming pool liners are custom shaped to the pool with seam sealed  side to floor  joins so last alot  longer with thinner materials no stone in them  either.

Rubber spray on shells To  expensive  for pros landscapers to use : 

 The next evolution is  sprayed in rubber like compound on  concrete or timber form work this  makes a 4 to 5mm thick walled custom  pond  base Expensive  but good and  you wont hurt it with rocks in it, and standing on it like pond liner sheeting.   But this  can break down over time to UV you might paint it as a sort of sunscreen to slow this down

As for clay pond bases I have never hear of any that being successful  I mean totally water tight unless it was  treated with polymers as mentioned in farm ponds on that scale.  I dug my pond into near pure ground clay this stuff you could pick it up and start making model  shapes out of it but it fill in rainy days but it drain with in 24 Hours. So water will find it way.  I suspect clay ponds will leak a  percentage into the ground? Ok if you dont have to pay the water bills.

Just to give you some credentials  as to a successful build.  Pros landscapers rarly use  due to expense and time to make.  Lets  face it they want to make faster bucks for a cheaper outlay in out thanks for your money.

9000L cement and brick pond no cracks

9000L Cement and brick pond built to last and not fail like under designed concrete ponds  often do in earlier attempts  as water is  very heavy that is 9 tonnes of water on top of a cement slab need to get that one right first time.

So how thick should the concrete be  for my pond.?  

   I used 300 mm thick double steel reenfored concrete for the cement base with  half round fillet corners with mesh webbing to transition water weight/pressure gradually to brick walls ,  Gravity  goes straight down so regular double brick walls are not under huge strain. 

Will it  fail? NO I build to have it out last me and  beyond  no short cuts on key structural projects.  Back yard  pools tend to be around 150 to 200mm in the base depending on the concreter.

Stage  1 is the top section of the  pond build when I had less ideas of fishes needs.  Gold fish  where fine koi where wallowing in the shallows. I did have a 10mm thick aquarium glass front originally. To explain the wings of bricks in the pond.  It looked  good.

Stage 2 is the lower section  Koi need a deeper cooler water for higher fishy happiness.  Koi treated right can live 30 plus years thats  longer than cats dogs and many pets and they do learn and remember  people contrary to many peoples thoughts of brainless animals.

It was challenging marrying the  two pond stages as I had to undo bricks and interlock them so it wasn't a Butt join doomed to a leak failure.

Cut some holes in the brick  wings for better water flow  also for fish interest rather than a box of water. 

I fully  filled the pond to test the concrete for  2 months  Rock Solid  is the verdict , Stage one is 15 years old stood the test of water and time,  Now I am starting to add a purly cosmetic layer of glass tiles.  AS why go to all this trouble just  to look at concrete.

The Rendered looking coating  is several layers of Silasec over the top of bondcrete sealing layers this stuff is pure gold as it is UV safe as all concrete surfaces. Totally water proof was my goal for a long lasting pond solution all else  are fails.

This journey  began in  earnist as the first pond stage was painted with  crommelin blue waterproofing made for ponds was  not stated as UV proof. 2 years later and it peeled and  failed.  Never assume a product is UV  safe  unless they state clearly it is.   So I was badly bitten.