Design wise you should never rely on sealing up rocks to contain water. That is the job of the liner and why the edges always have to be above the water line even at the falls.

Large rocks can be used on the outside of the liner to support the vertical portion of the U shaped cross section needed. Large rocks on the outside work best for structural support and to address the elevation change.

On the inside of the liner use large flat rocks to form any steps and the spillway. Then smaller rocks to hide the inside of the liner on the vertical surfaces. Use black waterfall foam under the all the rocks inside the liner. This is done so most of the water flows over the rocks rather than under them.

The key to a beautiful natural looking waterfall is to use different size and shape rocks, dry fit them before foaming them in place and think of how water flows. Shingle the rocks over the rocks and the liner over the pond liner. This requires working from the bottom up and outside in.

When you start laying out the outside structure for the liner support, keep in mind to make it large enough to account for rocks on the inside or the water way will be too small. Trim off any exposed foam and your done.

Mike K

Thanks! :)

My thought for using the glue would be to have the liner basically attach to the outside of the inside rocks. Forming the u/cup shape. So overlap and then fold up. That way the rocks are supporting the liner but are within the liner, not outside it.

One side of the falls is against a fence, so the liner isn't going to be visible on that side. On the other I was going to hide the visibility of the liner by putting more rocks along the outside edge. I also got a very small (pondmaster 1000) waterfall filter box, so I need to incorporate that into my design.

The liner I was using was leftover and not nearly large enough. I got a new liner so I'll have plenty to work with. I also am going to overlap into the pond more to hopefully eliminate any gaps.

I'm actually amazed at how much water can leak without leaving more than some damp earth on each side of the falls. I was losing over a foot in depth within 6-8 hours. Took the pump hose out of the falls and just have it running directly back into the pond. Don't think I have seen any noticeable loss in water level.

Lesson learned. :)

YOU GOTTA SHOW PICS!!!lol! We LOVE pics!! I was going to suggest the pond foam stuff too, Luv that stuff! Good to go with a bigger liner too, so sounds like you have it under control! I had an issue with the fact that I built a part of my pond wall with burlap sacks, filled with sand. Well, the winter weather/rain, came and rotted the burlap and when I drained the pond to clean it...yup, you guessed...it all collapsed!! Arg! So esson learned....rebuilt it with cement and building blocks, now is perfect and better! The lesson this year, so far, for me, is that an otter has been back and yes, ate my babies, but was very rude about it, and pushed some rocks...the only ones I didn't cement in, or pond foam in place, they are laying in the pond...grrr, and they will stay there till the weather warms up, cuz I ain't going in there till that water is warm!lol! Live and learn....

Rebuilt it today. So far so good, no water loss noticeable. Also now have the waterfall filter, a more powerful pump, and a submersible filter.

I also have black waterfall foam everywhere, LOL. Once I cut it back I'm thinking I'll put some silicone on the visible parts and throw some sand on it to hopefully make it more visually appealing.

I'll see if I can get some pictures tomorrow. :)

Good Job! I forgot to tell you a little foam goes a long way. looking forward to the pic's.

{{gwi:201177}}

Pardon the hose, yorkie (she was like-- "whoa, this is the biggest water dish I've ever seen!"), and the plants that I stuck in the falls stream till I can get them planted.

Obviously I still need to work on masking the liner in the waterfall. Also all the traipsing around the bog pushed my retaining wall out of line. Going to need to dig down and reposition the bricks-- and fish the one that just fell into the pond last night out.

Are there any plants that would work in small netpots along the edges of the stream?