Pond liner and concrete wall

[GBBUDD]

Okay. Will do. I feel like okay I’m feeling better about this now. One other thing I’m going to start reshaping and cleaning the inside of pond to get ready to lay liner. The dirt from under the cement I laid has washed away. Since I’ve left partially uncovered through a few rain spells and water seeped under tarp. The circled marks is no longer under the concrete. It’s just the concrete shelf now. Dirt washed down into pond. How do I fill up under the concrete wall? Any suggestions? Not sure if it’s possible to backfill soil some how? How can I clean this up and add the shelves back? Thank you so much. You always give great advice. You helped me add my shelves back to that other side in an earlier post when I first signed on. Appreciate it again

You are getting a problem too much soils has washed out. That concrete looks like it is already failing and falling in. Not being there I would pour an other concrete pad below it at lest 4 inches thick if not 6 then apply a nailer on it running along the lower new slab. Install some 3,/4 ply wood vertcly but you'll have to support it without using the concrete above for the most part as you'll need to get concrete in there. You can use braces into the new pad below and few in the pad above.
I had similar but much worse happen s my excavation was a good 7 fet deep but not by the time winter was over and mother nature filled it in a bit washing out under my patio. I had to build a retaining wall of concrete blocks to keep the patio from falling in. It's in my blog below this post.

 

[GBBUDD]

Okay. Will do. I feel like okay I’m feeling better about this now. One other thing I’m going to start reshaping and cleaning the inside of pond to get ready to lay liner. The dirt from under the cement I laid has washed away. Since I’ve left partially uncovered through a few rain spells and water seeped under tarp. The circled marks is no longer under the concrete. It’s just the concrete shelf now. Dirt washed down into pond. How do I fill up under the concrete wall? Any suggestions? Not sure if it’s possible to backfill soil some how? How can I clean this up and add the shelves back? Thank you so much. You always give great advice. You helped me add my shelves back to that other side in an earlier post when I first signed on. Appreciate it again

You are getting a proem too much soils has washed out. That concrete looks like it is already failing and falling in. Not being there I would pour an other concrete pad below it then apply a nailer on it running along the lower new slab. Install some sheet of 3,/4 ply wood vertcly but you'll have to support it without using the concrete above for the most part as you'll need to get concrete in there.

Or you could try and dig out and stuff bricks in there but that's a bit dangerous. That slab looks ready to fall in now.
Baby blue is 3/4 ply wood
Yellow is braces tap coned to the concrete or what ever way is easiest to secure the plywood to hold back the weight of the concrete.
Purple are nailer

 

[newponddiyer]

When you start your pond…..you want it to be right, from the start. That was my reason for the pond rebuild with a collar. Clay ”soil” slippage and water hippos (where water from the water table creeps under the liner and pushes up on the liner.). I had a good berm built, but gravity was stronger than my berm. I know what you mean about rain and clay.

Personally, if it was my pond — and I’m sure you have a LOT of time and effort invested already — I would TRY to start over. Don’t worry about underfilling the concrete — I honestly don’t think that is going to work for you — but that’s just MHO. When I redid my pond, in order to make things work, I had to go bigger, wider, to make up for what wasn’t there anymore. You need a good level, solid foundation for that concrete.

Are you using rebar with the cement?

I wouldn’t mind starting over. The people that were going to add to the concrete I already have is using rebar. The little bit that’s poured already doesn’t have any. It was poured so there wasn’t just dirt under the liner to hold the soil. How would I start over? Thanks again.

 

[newponddiyer]

You are getting a proem too much soils has washed out. That concrete looks like it is already failing and falling in. Not being there I would pour an other concrete pad below it then apply a nailer on it running along the lower new slab. Install some sheet of 3,/4 ply wood vertcly but you'll have to support it without using the concrete above for the most part as you'll need to get concrete in there.

Or you could try and dig out and stuff bricks in there but that's a bit dangerous. That slab looks ready to fall in now.
Baby blue is 3/4 ply wood
Yellow is braces tap coned to the concrete or what ever way is easiest to secure the plywood to hold back the weight of the concrete.
Purple are nailer

Good info. I’ll see if it can be fixed or secured it had dirt under that I refilled so it as concrete poured over loose dirt and then the rain washed it away the refilled dirt. I could just cut the concrete back to align with the dirt it’s on top of. We shall see. Work in progress. I’m patient. Appreciate the tip!

 

[GBBUDD]

The only loose soils will compete over time then the slab will want to fall in the pond or Crack either way when it to is covered in stone the last thing you want is to have things falling into the pond