CW's Back Yard Water Garden Begins!

[GBBUDD]

MOLES not good anything that can burrow through soil can easily poke through rubber.
Poisons as a temp fix to keep them away from the liner they will sence it and stay away. But I'd only bet it's a temp fix.
I have also seen where chicken wire was used. But I see that as a potential problem when it rots out and then there's concrete blanket. But I believe that's in 3 foot sheets

 

[addy1]

We have moles, voles, mice, none have gotten though the liner. I have tunnels everywhere in the yard esp after winter.

 

[combatwombat]

@addy1: Glad to hear that. From the research I've done, it seems the most vulnerable areas are around a waterfall where chipmunks/mice will sometimes nest and shred things up/chew holes. That's where I see all the pros investing in hardware cloth or concrete cloth. Down below the water line seems to be less of a risk.

 

[addy1]

So far they have not bothered the waterfalls I have or the stream. It has been 11 years now. We have chipmunks they show up now and then.

 

[combatwombat]

Made the commitment to reversing original pond flow. Old, enormous intake bay now = properly sized wetland filter. Spent all day digging.

Dug the pit down to 30" to accommodate:

• 8" of cobblestone
• 8" of river rock (or cheaper round stuff)
• 8" of pea gravel
• 3" of water
• 3" of freeboard

Then sloped the base down to 36" at the center to allow drainage of solids to the centipede, which will be a 12" HDPE drainage pipe sitting in a trench of the same depth, sloped 1/4" per foot towards one side in order to drain solids into the snorkel—an 18" drain pipe—to be pumped out as needed.

Here's the wetland area w/ the centipede trench dug:

Bottom of 18" snorkel is 12" below bottom of centipede trench to allow collection of solids:

Leveling the snorkel (it'll get cut down to water level once rock is in place and pond is full.):

Still figuring out how tall the snorkel should be. The Aquascape literature and all the pros I watch on Youtube say that it should be just above water level. But the tutorial at bogfiltration.com specifically instructs you to set it just below water level to prevent mosquitos from nesting in in the still water inside.

The extra digging produced a pretty big mound of dirt, which I just threw to the side of the pit. That space is supposed to be where I place a gravel patio and fire pit, but now I'm eying it as a potential waterfall location. Might be tough to sell the wife on that change order, though. Going to have to paint a good picture of where that space can be if I take it over for a waterfall.

The mound is much too volcano/ant hill looking at the moment, so cutting it down and fanning it out towards the back corner of the property.

Once that's done, will reposition the liner and move onto digging the new intake bay at the other end of the pond.

Off to drink a beer and start again tomorrow.

 

[brokensword]

Made the commitment to reversing original pond flow. Old, enormous intake bay now = properly sized wetland filter. Spent all day digging.

Dug the pit down to 30" to accommodate:

• 8" of cobblestone
• 8" of river rock (or cheaper round stuff)
• 8" of pea gravel
• 3" of water
• 3" of freeboard

Then sloped the base down to 36" at the center to allow drainage of solids to the centipede, which will be a 12" HDPE drainage pipe sitting in a trench of the same depth, sloped 1/4" per foot towards one side in order to drain solids into the snorkel—an 18" drain pipe—to be pumped out as needed.

Here's the wetland area w/ the centipede trench dug:

View attachment 137910

Bottom of 18" snorkel is 12" below bottom of centipede trench to allow collection of solids:

View attachment 137911

Leveling the snorkel (it'll get cut down to water level once rock is in place and pond is full.):

View attachment 137912

Still figuring out how tall the snorkel should be. The Aquascape literature and all the pros I watch on Youtube say that it should be just above water level. But the tutorial at bogfiltration.com specifically instructs you to set it just below water level to prevent mosquitos from nesting in in the still water inside.

The extra digging produced a pretty big mound of dirt, which I just threw to the side of the pit. That space is supposed to be where I place a gravel patio and fire pit, but now I'm eying it as a potential waterfall location. Might be tough to sell the wife on that change order, though. Going to have to paint a good picture of where that space can be if I take it over for a waterfall.

The mound is much too volcano/ant hill looking at the moment, so cutting it down and fanning it out towards the back corner of the property.

Once that's done, will reposition the liner and move onto digging the new intake bay at the other end of the pond.

Off to drink a beer and start again tomorrow.

I know you may not want to hear this, but take a moment to consider; with a cleanout/vault system, it'll work a LOT better if you slant your floor toward your vault, too. Not just have a lower area for solids. And, though you may or may not have this option, you should slant your walls that way too. Make the walls/floor into a V shape. This is the reason; when/if you ever have to clean your bog out, it won't necessarily be from solids on the bottom, it will probably be because the bottom of your topmost layer (the pea gravel, and I'd recommend 12" min, not 8") will be clogged. The way you clean a bog is to backflush using a feed from your pond pump. It needs to he a hard, heavy flow to do the job. When you backflush, you'll push the water now from the top, forcing the clogging to loosen and drop to the lowest area, and if you sloped everything right, to a single low channel then a lowest point. This is where you vault/cleanout is. When you drop another pump then into this cleanout, you'll get everything; the solids and the smaller clogging pieces. You'll pump it out, backflush again, pump it out, backflush and repeat until you get clear water flowing out. I was told by a pond professional it usually takes 2-3 backflushes. I've never had to do this, though I did dig up the whole bog v1 to clean it. MY mistake was not in the lower trench/cleanout portion but in making my walls straight down. That's why I 'm suggesting the V shape so EVERYTHING goes toward the trench and then to the cleanout.

Your main trench pipe is the 'centipede' with the slits. The same guy told me to place the slits up, this is so when you backflush, the swirling/dropping particulate can get into the center tube and is sucked into the cleanout as you pump it out.

So, IF you can, I'd suggest altering your bog area as described above for maximum effect.

re the height and top; I also was told to have the top just below, with a hole in the cap. What I found is this; the water, since it's NOT under any backforce of pressure as there's no stone in your cleanout, can easily be forced up through this cleanout while avoiding the gravel you so desperately want the water to rise up through. In effect, bypassing the bog. So, I put some foam padding and even a layer of pea gravel INSIDE the snorkel portion to stop this.

Now, IF you have the cleanout snorkel higher than your bog level, the water should NOT be able to be forced. So, my recommendation is to make it higher, as high as 12" and you'll make the water's path of choice be the bog/gravel as there'll be more head via the snorkel than through the gravel.

Almost forgot; with the height above the water, you can make your own top out of anything you can cut and just zip tie it to the culvert tube. Can do the same below the gravel, if you go that way. My diy cleanout was a bunch of buckets stacked with cut out bottoms, so I could use an original lid. This was for bog v1. With my bog v2, I used a plastic garbage can and have it raised above the gravel and filled it with more gravel for some iris. I'll have to dig the gravel out if I ever have to clean, but it isn't much more than about 5 buckets of pea gravel and easy enough to scoop out to gain access for the aux pump. The aim is to never have to do this!

 

[combatwombat]

@brokensword: I'm a little confused. The way that you're describing the slope of the bog sounds like how I did it. My walls are not slanted to the center (not sure why that would matter?) but the floor is. And then the centipede trench is slanted towards the snorkel. End result should be that anything that settles or is backflushed should make it to the snorkel.

If you're describing something different, maybe you have some pics you could reference? I'm basically following the instructions from bogfiltration.com.

That's interesting about the snorkel becoming a pathway for the water to channel through instead of the gravel. I have heard about that problem. So, if snorkel terminates above water, no problem? And if it terminates below water, potential problem?

Why not terminate under water and fab up some kind of plug for a cap? Ponds are pretty low pressure systems, so I imagine a cap would not have to withstand much pressure? Maybe that would be an instance where paying $50 for a cap designed for these drainage pipes would be worth it.

 

[Lisak1]

Not sure if this is helpful, but our snorkel in the bog is installed so the cap is just above water level. The top of the snorkel is right at water level. To me, putting it below water level means you could have issues with gravel falling in when you remove the cap, no?

 

[brokensword]

@brokensword: I'm a little confused. The way that you're describing the slope of the bog sounds like how I did it. My walls are not slanted to the center (not sure why that would matter?) but the floor is. And then the centipede trench is slanted towards the snorkel. End result should be that anything that settles or is backflushed should make it to the snorkel.

If you're describing something different, maybe you have some pics you could reference? I'm basically following the instructions from bogfiltration.com.

That's interesting about the snorkel becoming a pathway for the water to channel through instead of the gravel. I have heard about that problem. So, if snorkel terminates above water, no problem? And if it terminates below water, potential problem?

Why not terminate under water and fab up some kind of plug for a cap? Ponds are pretty low pressure systems, so I imagine a cap would not have to withstand much pressure? Maybe that would be an instance where paying $50 for a cap designed for these drainage pipes would be worth it.

I can't tell that from your pics, so I assumed you did a flat bottom (and straight sides) while having your trench angle to your cleanout (which is correct). The pro I got my directions from mentions slanting the sides, too, to form more a V. Says it helps with the backflush and I could see if anything gets dislodged from underneath the upper gravel layer, that it might indeed be harder to move into your center trench low area and out to the cleanout. Remember, you're using a top flow to move anything toward your center tube then to the clean out and unless you have a very powerful alt pump in the cleanout, you're depending on suction to grab anything on the edges. A flat bottom or even one only slightly angled, is asking a lot. A V shape uses engineering to help that problem.

Just looking again at your sides again, they seem pretty straight to me as well as your bottom sure doesn't show much pitch toward the center. This was the one area I regretted (upon learning of my error) that I wished I'd known before hand. The pro's directions were not that clear and I did not do as I'm telling you; it wasn't until I talked to him via phone personally that I understood he should have delineated that fact more clearly (I saved all his pics and there's only a small reference to the V shape). So, that's why I'm at least informing you at a stage you can still do something about it, if you want to. Otherwise, it looks great.

And yes, I'd have the top higher than the gravel, by at least 6", to help the problem go away. I did the pad/stuff the tube trick and it doesn't work as well as you'd think unless you fully plan on sealing it. I was also told to leave a small hole near the top (I forget the reason why; think it had something to do with mosquitoes, but I digress) which didn't help the problem. If you can totally seal off the vault top, this shouldn't be a problem but water pushing up and encountering rock that might get clogged (even partially) is going to put more pressure on any avenue with less restriction (your vault cleanout tube), so make sure the top is able to handle this. You're not just working against rising water, there's a pump pushing behind it.

Still, your system looks really good; just trying to show how to modify if you want even better efficiency/ease of cleaning.

 

[GBBUDD]

3" of freeboard

I would double this number

 

[combatwombat]

@Lisak1: Yeah, that would be one of the hazards. I think the idea is to gradually slope the gravel around the snorkel so that there is still a lip above the gravel to prevent that from happening.

@brokensword: Okay, I think I understand now. My pics are probably deceptive. The floor slopes 6" over 4' which is pretty aggressive, I think. I could probably make it even more aggressive without much effort, so I'll plan to do that before placing the liner. Doesn't hurt!

I would double this number

I would, too. However, I've already raised the grade at that location beyond what I think looks very good, so raising it even more would present a real space + aesthetic challenge. Would probably have to construct a short retaining wall to achieve that. If I can come up with a way to do it that still looks good, I'll do it!

Everyone says the additional freeboard is a good safety measure, but as a newbie to bog building, I don't totally get why it's necessary. If your spillway is 3" below your liner edge, how does the water get so backed up that you need more freeboard? Is it that the plants grow into the spillway and dam it up or something?

 

[combatwombat]

Alright, knocked down the volcano this morning and starting to see how I could have a very cool 10' stream cascading about 12-18". Not exactly niagra falls, but could look and sound great w/ enough water running over it.

After planting the berm up, I think it would look really natural. Now I just have to figure out where to move the fire pit and sell the vision to the wife. Wish me luck.

 

[addy1]

I'm basically following the instructions from bogfiltration.com.

Just went and looked at that site, lots of info. Nothing like that around when I did my basic, but works great bog.

 

[brokensword]

Alright, knocked down the volcano this morning and starting to see how I could have a very cool 10' stream cascading about 12-18". Not exactly niagra falls, but could look and sound great w/ enough water running over it.

After planting the berm up, I think it would look really natural. Now I just have to figure out where to move the fire pit and sell the vision to the wife. Wish me luck.

View attachment 137931

mention all the great looking and smelling flowers that'll be dotting the new landscape, all the flowers YOU'LL be picking for her...then casually insert the new stream...something like that!

 

[brokensword]

Everyone says the additional freeboard is a good safety measure, but as a newbie to bog building, I don't totally get why it's necessary. If your spillway is 3" below your liner edge, how does the water get so backed up that you need more freeboard? Is it that the plants grow into the spillway and dam it up or something?

you'd be surprised how aggressive roots of the bog plants and possible clogging down below can push the water level higher than you'd expect. Remember, the pump will keep pushing despite this. I know I'd have a minimum of 6" extra liner to take care of this potential problem, hence my back and sides of my bog v2 are that way. It's an easy thing to do now and a lot more issue if one develops later, to fix.