Ten Ton Pond

The story of our garden design and build

Let the work commence!

This is how things looked at the end of Day 1. You can see that the concrete slab is gone. You can't see that he's demolished the steps that led up to the garden (to get the digger in). We set up a camera in the bedroom window that overlooks the garden on a tripod and took a photo every day. It didn't stay in exactly the same place through the work, but having this record means that we have the pictures to show progress from a common viewpoint.

At the end of the next day, the upper part of the garden was being levelled and a couple of large cedar tree stumps (there's one on the right of the picture) had been taken out. A couple more skips had been filled and the hole for the pond is beginning to appear.

At this stage, things are really beginning to take shape. The hole for the pond has been completed and also the foundations holes for the gazebo structure are there. The gazebo 'kit' had been moved up from the front garden and is up on the left of the picture.

If you look carefully you can see leveling pegs at the bottom of the pond hole, along with the reinforcing mesh. The slightly deeper trough along the width of the hole is where we stumbled across an old land drain. This was lucky, as we were able to use this to feed the drainage from the filter area. Otherwise, we would have had to dig a soakaway, or find some other means of getting rid of dirty water from filter cleaning. Note that this picture is a bit misleading: the base wasn't actually ready for concreting as there is no pipework for the bottom drain (if you don't know what I'm talking about, look at the 'Technical' section).

Here, you can see that the base for the pond has been concreted. The orange pipe standing at the far end will go to the filter and although it isn't visible, the bottom drain is in the centre of the concrete base, which is slightly 'benched' - that is, sloped towards the drain. There would be more concrete in the hole though, as the filter bay would also have a concrete base. On the right are the blocks that will form the pond structure.

On the left, you can see that the foundations for the gazebo are also in place, with a single course of bricks. (well, you can see two of them). you can also see the builder's level marking where our decking will be.

More excellent progress! All of the blocks in the bottom of the pond are actually holding out the boards that were used to pour more concrete. This forms the foundations of the walls, and reinforcing rods are there to give strength to the finished structure.

The next activity was to build up the walls, threading the hollow blocks onto the rods as the layers were built, and then filling the void with concrete.

And here, we see quite a lot of progress. the front wall of the pond is to its final height - and the oak gazebo structure is up! You can see that it sits on brick pillars on top of the concrete foundations. This isn't going anywhere! You can see (just) the lead capping on the brick pillars but you can't see the stainless steel rod that locates the uprights in place. This is a very heavy structure; the long horizontal beams are 4m x 20cm x 20cm, so that's 0.16 m³. Given that green oak has around the same density as water (1,000kg/m³) each one weighed about 160kg. They had to be raised 2m from the ground.

Some time later, the project really looks as though it's taking shape. The walls of the pond are complete and the joists for the decking are (mostly) in place. We made the decking the same length as the longest boards that we could find (4.8m).

You can see at the front of the picture the nosings for the steps being assembled and there's one on the pond wall. These too are green oak, which is an excellent material to use as it is rot-resistant without treatment, very strong and surprisingly easy to work. Here, I must say a word of praise for our builders, who were fantastic. They helped me enormously with design decisions, advising where there I was proposing to do something that was gong to end up being un-necessarily expensive and then did exactly what they'd agreed. Most often, where there was a decision to be made, they proposed just the solution that I had wanted. And I feel sure that the garden will prove be a lasting testimony to their work.

Here's a different perspective. You can, I hope, see part of what inspired us with this space - we are very lucky and have a lovely view across a valley. Immediately below us is an allotment ground, which means that the view is a nice open one. This view is south-westerly, so the garden gets plenty of sun. At the edge of the garden is a drop of about 1.5m, where there is a lane that leads to some garages - so we're elevated above the allotments.

Anyway, under the decking joists you can see weed-suppressant matting. The oak structure is beginning to 'bleed' tannin, as evidenced by the dark brown stain on the brick pillar foundation.

This picture shows more-or-less how the steps are constructed. They're made from green oak sleepers, and are assembled with cross-halving joints (with invisible fixings - the builders' attention to detail was superb!) They sit on notched joists that are in turn bedded into concrete foundations.

This seemed to me a bit messy at this stage. This was really due to the slope of the garden. Next to the pond, the steps are built onto a large lump of concrete, which you can see is being temporarily shored up as it sets. Also, on the left is a piece of wall that re-uses some of the ashlar blocks from the 'step' in the old garden.

I included this picture just because it shows better how the steps are built.

I spent quite a lot of time in the filter end of the pond, just puzzling how best to do things. There's a lot to think about with this, from deciding what types of filters to have, through to the practical issues of ensuring that the services are convenient and won't be too difficult when we come to the regular maintenance that will need to be done when the pond is in service. The pond needs water, air and electricity. I haven't plumbed a water supply to my pond though - I'll have to use a hosepipe to supply water for top-ups and filter changes.

The grey circular thing looking like a dustbin is the filtration unit. It is a Nexus Eazy Pod and depending on who you talk to is either the bees' knees, or a gimmicky waste of money. If you're interested in why I chose it then look at the 'Technical' section (though there's a clue in the very limited space that I have available!).

I bought an EPDM 'box liner' to keep the pond water-tight. I'd read lots and lots of pond build stories and know that people like to use fibreglass, but it's quite a bit more expensive and the 'rubber' liner comes with a 30 year warranty, so I plumped for that.

The pale grey material is a sort of man-made fibre felt underlay that is supplied along with the liner. I'd previously thought of using some old carpet for this, but of course light lining was very inexpensive and was much easier and quicker to fit. Fitting the underlay and liner only took me a few hours (and I'm a slow worker!). The liner was heavy and somewhat unwieldy, but otherwise was very simple. In the picture you can see the water inlet to the pond on the far wall. This position was really dictated by the position of the filter, pump and ultra-violet steriliser.

It simply wasn't possible to fit the liner with no sags or creases - I don't know what the answer to this is. Our liner was 'flanged - had a fitted lip to go over the pond edge and I guess it might be easier with a non-flanged liner, but I did like it that the corners of the pond were really nicely finished (even if this detail isn't really visible!).

I would imagine that trying to do this with a single sheet liner would be really trying!

At the end of the day, the pond is ready to be filled. I felt good.

The only nerve-wracking part of the job of fitting the liner was cutting holes in the liner for the bottom drain and the water inlet. But it has to be said that modern materials that are available are brilliant, and it was all done without any real drama.

I was very pleased to finally be filling my pond with water! Turning on the hose was a great moment.

Within 15 minutes of turning on the water, we had a visitor! It's a shame in a way that this couldn't also be a wildlife pond, but with our design it's just not possible as there's no way out for ampihibians.

As the pond filled, I spent some time screwing on the deck...

... and it's no mean feat. There were about a thousand screws to be driven home. What with cutting the boards around the legs of the gazebo, it took the best part of two weekends.

After the pond had filled, the sun came out... The pond water looked so nice and black, and the pyracantha berries look lovely and bright. This picture gives a misleading illusion of completeness though. There was still a lot of work to be done.

Once the decking was done, things felt much more complete. In this picture, you can see the coping stones ready for fitting - there are a couple on the corner of the pond and a pile of them on the right.

Nearly there! The coping stones are fixed and the outside of the pond has been rendered. We had originally thought about making the outside from reconstituted stone blocks, but this was really expensive (and interestingly not that much cheaper than using actual cut stone!). The render was done with white render made with yellow-ish sand. It's quite a good colour match to the coping stones and we're very pleased with it.

This is where the builders stopped work. We felt that the rest of the work was within our (my) capability to do without assistance.

What you don't see from this picture is that we'd done a lot of work levelling the top part of the garden. We used the excess soil to fill and level elsewhere. It's not particularly difficult, but it is quite hard work!

This detail shows the decking extended over the filter area. I think it makes the whole of this end look properly finished. You can also see that the decking edge is brought over the lip of the pond, which makes it neat

The bottom edge of the coping stone lines up nicely with the decking. I think that these details make a big difference. There are actually few details for the pond that haven't worked out quite nicely.

Levelling the garden after the rendering was a bit of a chore, which involved wheelbarrowing and shovelling 8 tons of soil. I'm very lucky in having a fit wife and mother in law! All I had to do was rake out the heaps of soil and tell them where to put each barrow-load.

I love this picture - you can imagine that all of the work is done! There's no sign of mud and it all looks very peaceful.

This picture looks so serene... It is very misleading!! When the turf was delivered on the Friday evening, it was in a heavy and prolonged cloud-burst. The turves were very, very heavy and very soggy and very slippery. The topsoil that we'd raked out was soft and spongy (to say the least!) and the work of turfing was tedious. But it does seem to be coming together, even though looking at the picture makes my back ache with the memory!

The edging around the bottom of the pond walls is a 'mowing edge' that's supposed to make mowing the grass a breeze - no need for a strimmer! You can also see how the steps are supposed to work - they're as wide as the lawnmower, so you just run it along the oak nosing and they'll look nice and neat in just a few minutes. Well, that's the idea.

Here's a nice picture of the detail at the top corner of the gazebo. Isn't it lovely?

This is how the pond looks at the moment (January 2012). We are very thrilled with it. It does have fish in it, but they're not easy to photograph, especially as in the winter they hardly eat and so don't come to the surface when I arrive with food... they just dive deep and stay there.

It's been very mild - the grass is even in flower. I'm sure it's not supposed to do that!

This picture is from another angle and shows how nice the turf is. In January, things usually look very scruffy, don't they? But this all looks nice and lush and green. Brilliant.