Small section of pond bank collasped

[Big Lou]

Along time ago the front section of the pond was converted from a small stream waterfall to just the front of the pond. Foolishly I hurriedly used sand to construct the bank. Overtime that sand slid under the liner and pad. Last week the bank could no longer support the top flat stones and the bank completely collapsed. Please note that I am not concerned about the sand that slid under the in pond liner and pad but must rebuild the bank or make an attractive shoreline. The pond is not leaking.

Please view the photo's and teach this old fool how to rebuild the bank. I need to the repair to be as non-invasive as possible and economical. Note: The stones you see on top of the liner are there to hold it in place and hopefully keep water from going under the liner.

Thanks in advance.
Lou

 

[sissy]

rocks would look pretty there with a plant in the middle of the rocks .Something like a mini cattail maybe

 

[Tula]

I had a similar type problem from how my skimmer was originally installed. The sand slid under the liner and the skimmer was sinking

We had it built up with rocks and solid pavers behind the liner, got the skimmer in level and so far, so good!! I was told I didn't want to cement things, in case we ever wanted to change the pond design - which I think was good advice.

 

[DrCase]

i would be mixing a bag of mortar. , kind of thick ,

 

[Big Lou]

Help me better understand Doc. Motar is generally used with bricks and blocks. Did you mean cement? Please provide details.

Thanks

 

[j.w]

I just shoved rocks in some low areas down in the soil to beef mine up in places. Mine's different tho as I have a little short ledge down in the water where my first rocks sit and then around the edge go the top ones.

 

[Priscilla]

I have the SAME problem! In my case, just inexperience and lack of reading up, rushing with the kids helping ...... so many things to blame. Kinda like when I built my deck, and just shoved the liner under it, without making it secure and tight ..... so many issues. In my case, its way too late, till my deck needs to be replaced.

JW, what are those yellow flowers growing into your pond? Love your edging!

 

[Big Lou]

Beautiful pond JW. I have some square stones that may work but I'll have to get the base sand level. Hoping Doc will reply back about his suggestion. Really want to solve this dilemma for good. Priscilla, the stories I could tell you about my novice deck building but hey it has lasted for going on 15 plus years.

 

[DrCase]

What I like about mortar is it has no rocks in
You can shape it real easy , once it dries it will be their until you bust it up with a hammer

 

[Big Lou]

Thanks Doc

 

[j.w]

I have the SAME problem! In my case, just inexperience and lack of reading up, rushing with the kids helping ...... so many things to blame. Kinda like when I built my deck, and just shoved the liner under it, without making it secure and tight ..... so many issues. In my case, its way too late, till my deck needs to be replaced.

JW, what are those yellow flowers growing into your pond? Love your edging!

They are called Creeping Jenny: https://en.wikipedia.org/wiki/Lysimachia_nummularia and can really try to take over but real easy to just clip the runner or pull where you don't want them to travel. Love how it crawls right into the water.

 

[Big Lou]

I can't wait until mine start blooming!

 

[Litzi1964]

I had similar problems with my pond. One area of my lower terrace collapsed, and the ground under the perimeter pavers shifted so much they were loose. In the past year we've had huge amounts of rain and snow, and the ground got soft and it expanded.

In an unrelated problem, my liner tore so I used the opportunity to take everything out and start over. For the lower terrace, I dug until I was at the clay layer, about a foot down. I will be building a support structure out of 40 lb cement blocks and mortar. I told my husband I don't want anything moving unless we have a direct tornado hit or an earthquake.

Adding lime or cement powder is good to harden up clay soils.

 

[Mmathis]

Lou, I couldn't tell much from your pics, but from your description it sounds like the soil [sand] under the liner at the edge gave way and collapsed into the pond -- is that it?

We've recently had a similar situation and the pond is currently "down" as we finish up on the repairs. We have clay and a lot of ground water, so we needed to stabilize the wall edges all around the pond -- lots of hard work for one with only occasional spousal & teen-ager help....! We chose to build a cinder block wall along the 2 sections that had previously collapsed, then a cinder block collar tied those 2 walls together. Won't go into details here, but if you want, I can PM more info.

Actually, the collar part wasn't that hard to do, but did involve a little digging.

But this might be something you can do fairly easily. As one poster has already mentioned use mortar -- I have discovered a technique that uses cement [Portland cement, not concrete mix], sand [mortar is cement + sand], and your native soil. I think it's called "dirt-crete." How creative. But basically what you do is mix your dry soil, sand, & Portland together with a tiller -- don't ask about proportions, though, as I just threw them together. Then use that amended "dirt-crete" mixture to build up your wall, berm, or whatever. Then tamp it down well. I don't have a site that I can refer you to, 'cause most of what I found didn't use it this way, but as walk-ways or backfill.

The addition of the Portland to the native soil acts to stabilize the final product.....we'll see how that works.

So, we have a cinder block collar. The berm will be "dirt-crete," as mentioned above.

 

[Big Lou]

Thanks M, I don't think my problem is that dire but I appreciate the information.