Darksaber Pond - My Next Adventure

[GBBUDD]

I'm digging his stats its much as i felt that 3/8 pea stone was a fit to fine. I mixed 3/4 river rock with 3/8 river rock for my bog.

 

[milonedp]

More rocks, shaping the pond, grading, and digging out more of the wetland filter.

 

[milonedp]

I have a question for everyone. The plan has them putting sand between the wall and the ground on the side, this would be behind the second layer of geo-liner but inside the pond liner. There's no way for fish or debris to get to it so there wouldn't be waste there to decay.

Does anyone see an issue with this becoming anaerobic? Other issues / thoughts?

 

[Lisak1]

So underlayment, liner, sand, then more underlayment? Did they explain why?

 

[Lisak1]

Also... this is day four of digging? My knowledge of this kind of stuff is limited to my own pond. We paid for excavation and to have some big rocks moved and set, and help with the underlayment and liner. They were done in two days. I'm curious why it's taking them so much longer to dig your pond.

 

[milonedp]

So underlayment, liner, sand, then more underlayment? Did they explain why?

Yes, the sand inside the liner is to better lock in the walls, we are using the stacked slate walls to maximize the swim area for the girls.

As for the time, it's a few reasons, the days are short because the company isn't close to me so because of travel time they don't typically start till after 10 and finish around 4:30 because of travel time, they also aren't doing only digging, the truckloads of rocks had to be unloaded. The dirt (if you want to call it that, is a lot of partially weathered rock) which is terrible to dig in.

 

[Lisak1]

Ah... I forgot you were using stacked slate walls to line the interior. That makes more sense. My first thought was "how will they support the sand behind the underlayment?" Typically you would use sand between the ground and another solid surface - for example, a stack of Aquablox in a bog.

So they are backfilling between the underlayment and the liner. The stacked slate is a relatively new product to use in the way they are using it - if you have any questions or concerns I would call Aquascape directly. They are very, very helpful and can either reassure you that they are doing the correct install, or help you to explain to your contractor why they need to shift directions. We had them on speed dial when we were doing our pond build.

As soon as I asked you "what's taking so long?" it occurred to me that we have about 14 minutes of daylight right now! I'm sure they're doing just fine!

 

[milonedp]

Thanks. It's not so much the stacked slate that had me questioning things it was the depth of San that's be in the water and behind the wall. In reef aquariums we have to manage a deep sand bed so that it's either cleaned regularly or remains undisturbed as it can go anaerobic. I want sure about that with the pond. Aquascape has a video of their CAC in Australia that used a couple feet of sand in a beach so that'd have the same impact. Are anaerobic spots not as much a concern in ponds?

 

[Lisak1]

Oh they definitely are a concern!

My suggestion was to check with Aquascape to see if perhaps this is how they are recommending these walls be installed inside a pond. I would share your concern and wonder why the sand can't stay on the outside of the liner. I'd do (from the inside out) stacked slate, then underlay, then liner, then underlay, then sand, then ground. But that's just a guess based on standard pond building. We used sand to backfill our rain exchange and it was outside of the liner.

 

[milonedp]

Thanks, yes I've got a call into them as well, I appreciate that suggestion as I hadn't thought of that.

 

[GBBUDD]

i understand why they want to place the sand behind the stacked slate but to me i'd much rather see the stacked slate set on underlayment possibly doubled up and i would check the edges of the stacked slate as they could be sharp and i would ease the edges. but then have your liner and have the liner pulled over the stacked slate and the protection layer to the ruber and place the sand between those rocky walls and the base underlayment. fold back the liner and you should be pretty tight to the stacked slate . that would be my take but i have not used the stacked slate before. But having the sand outside the liner means its not going anywhere and your helping protect the liner in a big way from all those rocks.
But as far as the sand being a problem i would say not it is dense and will not allow sediment to mix in without being disturbed.

My question is what oz of non woven fabric are they using as underlayment or what are they using. That stone puncturing the liner is a real concern

 

[milonedp]

Thanks I appreciate the input.

I don't know the oz of the under and overlayment, I can ask. What should it be?

It's not stone though, technically its partially weathered rock, in all but one area in the wetland it's so weathered that it's not strong enough to puncture the liner, it looks jagged and terrible but without too much force it compresses. They completely packed the sides and bottom before the underlayment went down. The upper part that still looked rough will be backfilled with dirt or not part of the pond as there is going to be a retaining wall that runs against part of that back side.

 

[GBBUDD]

I know weathered rock and it can be very deceiving well i guess your very lucky in that regard. If it is highly weathered then a standard underlayment would do the job as like you said highly weathered is not strong enough to puncture anything i had some on a job site where the rocks were almost a foot thick and I took a chunk and said i could split it with my hand with a karate chop i bet the few guys around i could do it and made a couple buck when the second it hit it it just fell apart yet looked very much like a standard rock. i would still hope they plan on compacting the soils flattening everything weathered or not it can have a solid piece here and there

 

[GBBUDD]

The one thing i will suggest is planting pockets all they are is depressions in the excavation where the rubber and the gravel in the planting area can be deeper and you can remove the pots for lilies and such and still control them to a degree

 

[milonedp]

Yeah there are a couple of spots in the yard that aren't so weathered but most of it would tear right up, might be tougher than a karate chop but can certainly be compressed. Yes, they are compressing everything that'll be touching the underlayment, and any bad spots they said they'd use some of the sand.

I've asked them to is planting pockets at the edges in some areas, the way I asked though was for them to pull back the liner further from the edge then have rocks in front and back, some should be in the stream as well as the backside of the pond, in front of the retaining wall.

I wasn't thinking about using pots though, my wife doesn't like the lilies cause they grow all over, so I wasn't going to use them but if I understand what you are saying a pot would help control them from spreading?

I really appreciate all the input!