How to create the divider between the bog and the pond?

[Hop-frog]

Here is the latest design plan for my pond. It is not exactly to scale. I shared other ideas in the design previously, but settled on this as simplest and cheapest.

The orange circle is the pond (40 ft across). It uses a wall to keep out deposits from flash floods. So far, about half of the circular wall is constructed.

The bog is the rectangular part in the back (12x20 ft), at the corner of the fence. I'll use cheaper and larger cinder blocks here, and try to bury it such that is as invisible as is possible.

Due to the composition of the soil, being very loose dirt without a single rock in sight anywhere, small leaks quickly turn to disaster. As such, I plan to buy one huge liner shared by both the pond and bog (60 ft by 50 ft if such sizes are even sold). The wall separating the two can be built on top of the liner. It is critical that any chance of some leak developing, especially around the waterfall area, not be possible, hence the use of a single liner.

I suspect that, because the bog is higher than the pond, this will create a 10 foot wide waterfall. I tested the pump and it appears so capable, though I don't know if the bog impacts the return rate of water back into the pond.

Given both the bog and pond are sharing one liner, what is your recommendation for dividing the two compartments? If I am laying bricks on top of the liner, it risks exposing the fish to chemicals in the bricks, brick glue, etc.

 

[GBBUDD]

By the looks of your design you have at least a foot or two between the bog water level and the ponds . with that much a single liner is not necessary bring the pond line up and over the lip of the bog and the bog liner going down to the pond water level. this over lap is more the enough to control the water and insure there's no leak . But a single liner works as well but it can be challenging to get the wrinkles to work with you and not create a bit of a fight. If i caught what your thinking is to use cinderblocks for the down hill edge of the bog You are going to probably have some decent pressures within the bog . That wall should built solid And all edges eased over. Looking at your drawing it appears youll have a exposed down hill edge at 20 feet in length your could have a bit of exposed wall.. Actually this is almost a waste of time you keep showing computer drawings if you want actual help and opinion post some PICTURES of the area

 

[Hop-frog]

Okay, I will try to get some pictures to post at noon.

Yes, the bog is built up from a wall that is almost 3 foot tall. I can't build up to the fence, so the wall continues along the back. I don't know if the weight from the stones will be too much for this wall. It will be cinder blocks reinforced with rebar.

 

[GBBUDD]

Yes cinderblocks can hold the weight if built correctly

 

[Lisak1]

I agree with @GBBUDD - don't be too concerned about a single liner. If done correctly, two liners overlapping are just as effective and MUCH MUCH easier to work with. A liner the size you mentioned would weigh a TON.

 

[Hop-frog]

One thing also, the dirt isn't dug out completely from the center of the pond, I might pack it in the front of the bog, so there is a slope, then cover that with gravel. Not sure if that dirt put in front of the bog will help hold the wall up. But because I must stay 6 ft from the fence, there is that whole wall running parallel to the fence that is about 3 ft high and a straight drop-off. Unfortunately the pond has to be raised due to the flooding issue, so the bog is raised another 6" above that.

 

[Hop-frog]

One advantage of a single liner, is the plumbing can go through. If I have two separate liners, doesn't thepump need to pump up and over from the pond to the bog, meaning I'll have visible pipes?

 

[GBBUDD]

[QUOTE="Hop-frog, post: 452249, member:
Unfortunately the pond has to be raised due to the flooding issue, so the bog is raised another 6" above that.
[/QUOTE]
If you only have 6 inches bog to pond thats about minimal for a overlap between two liners it will work but it's close to where it could make for issues latter.

 

[GBBUDD]

Pipes. Can easily be hidden or you can use grommets for the penetration they have gaskets and theaded to each other tighten it and your done

 

[Lisak1]

Is your plumbing going to be inside your pond?

 

[GBBUDD]

Pipes. Can easily be hidden or you can use grommets for the penetration they have gaskets and theaded to each other tighten it and your done

Whoops not grommets but bulked

 

[Sisha]

If I could build my pond again I'd do a wetland filter and not a bog

 

[GBBUDD]

Um i am unaware of any difference in the builds between those two other then a bog has plants thrown in to the wetland filter.
Or are you referring to a aquablock setup over a peastone and pipe baffle

An why are you unhappy with your bog ?

 

[Lisak1]

If I could build my pond again I'd do a wetland filter and not a bog

That is a confusing statement, as we generally use those terms interchangeably here.

 

[brokensword]

yes, most here don't actually have 'bogs', but it is a term close enough and understandably easier to convey for those wishing a more natural filtration. We basically have an upflow wetland filter. A bog is typically efficient based on size as the water flows over not down and back up as its process. So, wetland and bog are more or less the same but an upflow wetland filter is the better idea relative to backyard ponds.