Gabion Stone Retaining Wall, Hillside Pond Optional

A gabion is simply a wire basket filled with stones. They can have many different uses, and if you have a stone yard nearby, they can be quite affordable. My 20 cubic feet were only $80, to create this 30’ long 2’ high wall!

I also make spiral shaped herb gardens with a similar technique. The possibilities are endless, and the skill level required is quite low! When you want an affordable stone wall, that is very attractive, and long lasting, this might be the project for you!

Supplies

Post hole digger, or gas auger, level, 4x6 pressure treated posts, Concrete for posts. 1x1” galvanized welded wire fencing(I used 24” tall, 4 rolls of 15’ length). Lag bolts with large head, or washers +than 1”. A roll of cheap landscape fabric (to help hold soil behind wall). Stones of your choice. A crowbar, staple gun.

Step 1: Pick Your Location!

Where do you want to build a wall? I like to follow the contour of the land, just at the base of a steep spot I want to flatten out behind the wall. I used a laser level to place flags every 5 feet on contour (level). My wall is 30’ long, so I needed 7, 4’ tall posts (half to be buried).

Step 2: Flatten Area

You will be putting the welded wire fencing on both sides of your posts, which will make a 3.5” gap that will be filled with your stones. It’s important to have a nice flat section for the bottom of your fence to set on the ground. You also will need soil to put behind your new wall when it’s finished, so whatever you dig out can be tossed up hill.

Step 3: Dig Post Holes

I placed posts 5’ apart to support the wire fencing. A gas powered auger really makes this step easier. Just be sure the length of your fence works with the spacing of your posts. Since I used 15’ rolls of fencing, 5’ apart, on center, worked for me. There will also be internal wire supports, so the weight of the stone doesn’t make your wall bulge.

Step 4: Pour Concrete and Plumb Posts.

I used about 40lbs of concrete for each post, and used a 2’ level to make sure they were plumb.

Step 5: Attach Fencing to Back Side of Post.

I used 1.5” lag bolts with a 1.25” wide galvanized washer with an electric drill to attach wire to the back of the fence. Make sure to keep your fencing level with the tops of your posts. The back of your wall will be back filled, so the spacing doesn’t have to be perfect, or quite so pretty on the backside. I had a helper with a crowbar to help keep the wire tight, but a couple ratchet straps could work, if your working alone. If your fencing is a tad wavy from unrolling it, don’t stress too much, the weight of the stones will straighten it out in the end, just attach it as tight as possible. Once the fencing is attached to your posts, you can attach your landscape fabric with a staple gun (to posts), on top of the fence (backside of wall) to help keep your soil from “leaking” through the stone overtime.

Step 6: Make and Attach Internal Supports

With scrap welded wire fencing, make supports that will hold the maximum distance between your two layers of fencing at 4”. To do this, count 4, 1” squares on your fencing, and then cut 2” wide pieces with 1” wire tabs on both sides (just short of the next weld) that will be folded around your two main fences (that are attached to both sides of your posts).

You will add these wire supports once you’ve attached the fencing to the back of your posts. Once they are attached, one every 6” of height vertically, and every foot horizontally, you are ready to attach the fencing to the front side of your posts. Just lay the internal supports flat, so they stay out of the way, they should swing like a hinge.

Step 7: Attach Front Fence Section(s) and Attach Supports

Since the front fencing sections will be visible, the symmetrical placement of the lag bolts/washers will be more important. I recommend 5 bolts per post (or every 6”). You can attach all of the front fence sections before attaching the internal supports. With the internal supports already attached to the back fence sections, you just need to swing the internal supports to the front sections as close to perpendicular as possible, poke your ends/tabs through front fence and folding around the wires of front fencing, making the maximum gap between the two fencing layers 4”.

Step 8: Fill With Stone!

The moment you’ve been waiting for! The beauty of your retaining wall gets revealed as you start adding the stone between your two layers of fencing. Let me know if you have questions, or what you think of this project!

Step 9: Add Ends, Backfill With Good Soil

In order to completely backfill soil all the way to the top of the ends of the wall, I added 4x6 posts, tipped on there sides, cut at an angle back into the hillside. The lowest piece was 10” long, angle cut, ground leveled, then screwed to the end post with 3” screws. Each post stacked on top was 10” longer than the previous, and screwed to the end post, and to the one below.

Comments

[Lighthouse]

It looks nice now, but most gambions that I've seen are more "cubical" in shape. I'm wondering if you really have the mass to prevent that hillside from eventually pushing through that relatively thin stone barrier by hydrostatic pressure.

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[Robnelson]

The landscape fabric will block dirt but allow water to seep through so hydrostatic pressure should not be an issue. The mesh and posts really do the supporting not the stone. I’m sure the gravel/stone still weighs a few tons.

[TimothyR11]

It took about one wheelbarrow load more than a ton for this wall, lol. Depending on how accurate the giant scoop of pond stone was. I think my math was about 20ft3.

[TimothyR11]

The landscape fabric on the back of the wall is there to hold soil back. Only the smallest particles would leak through that, and most of those clay particles are fairly sticky.

[Chimonger]

This wall was only 2’ high, and a gentle slope behind it...not too bad.
There really is a thing called “hill creep” by some, though.
To do a better job of holding back any more hill than this, I’d set the posts slightly tilted back towards the hill. You’d know when it was getting overwhelmed by hill creep, when the retaining wall started to look more vertical at any point.
Also, for taller retaining walls, the bottom can be made wider than the top, with that extra width slanted in on the hill side of the wall; that reduces the wet-load behind the wall, which reduces the “creep” of a wet dirt mass.

[obillo]

Great stuff, Tim, but are you certain it will hold? Gabion structure I've seen almost always have three or more rows in terraces. Maybe your locale is dry enough that you don';t have soaking rains?

[TimothyR11]

Thanks, we get quite a bit of rain here, but I think the wall is pretty solid. Water can just flow through the stones. In hindsight I might have put two rows of the bolts on the front posts/fence to reduce the stress on the wire where the bolts are, but all the internal supports hold it together well. The posts are quite solid being two feet in the ground. I have thought about adding a second shorter wall higher up the hill, just because there is room for another, but we’ll see.

[AndreasM2]

Very nice!

[TimothyR11]

Thanks :o)

[Brian1159]

Great project, I have a stretch of bank that I have been scratching my head for a while wondering what to do with it and you sir have given me the answer, so thank you and thank you for sharing.

[TimothyR11]

Thanks so much for the comment! Was my project in an email or something? I got a ton of views a comments all of a sudden.

[doncrush]

Can you share the spiral herb garden approach?

[TimothyR11]

Here is a picture. The basic idea is the same, just a bit more complicated geometry. It has internal supports in the 2" thick wall, as well as longer supports inside where the soil goes (around 1' long). I've made quite a few of them, and none are exactly the same, but similar. Let me know if you give either a try!

[hberryman.8]

Hi! I'm planning to build a gabion wall with hopefully 2"-3" stones, and so larger wire fencing, of course. Do you know if your design would work for that size stones too? It will be the same height as your wall. I also will be using STEEL tubing posts (in concrete) of almost the same dimensions as your wooden posts. Thanks.

[TimothyR11]

The diameter of the stones shouldn't change the weight much. My only question would be attaching the fencing to the steel would be a little more challenging than drilling into wood, but other than that it should be fine! Let me know how it turns out!

[tytower]

So what happens in 12 months when the wires rust through . Will it continue to stand on its own or will it all fall down "and all the kings men"

[TimothyR11]

You do bring out another strength of the whole concept though. The whole project only cost around $300 and about 1/3 of that is the stones themselves, which last forever. If/when the 4x6 posts rot or the fence corrodes beyond use, I’m guessing in around 15-20years, you still have the rocks to rebuild!

[JamesA41]

I've seen in MO where they just dig a pond on the hillside and what is dugout is used at the outer retaining wall for the pond built up a little more sloping like the gabion. Basically, all the clay sand or whatever that clayier soil is. Not other materials required. My guess if sandy or gravelly soil... then add the clay layer so the expense is in the clay layer or even maybe a pond liner material. Thinking can probably even use like a portland rammed earth outer wall or lining. Figured I'd toss out some ideas on the mind post reading the comments regarding cost effective ways that are longer term. Thanks for sharing!

[TimothyR11]

I have about a 10k gallon pond in the front yard. This wall was less about the pond and more about flattening the area to make it more usable, someone gave the me the little pond, and I like water features and might house a few ducks in the future, that could fertilize the fruit trees downhill. Hopefully it will all work out in the long run, thanks for the nice comment :)

[lushua12]

Any posts I bury or any part that is going to be in the ground, I always coat with roofing tar. It helps with prolonging the wood rot issue