Raised ponds have many benefits. They don’t have to involve digging and they can be built in a day, no problem!

A raised pond can prevent pets, children and wildlife from falling in. They look great too, and can really enhance a garden or patio. You can even disassemble and move house with them.

What materials do you need for a raised pond?

The easiest way to build a raised pond is with railway sleepers. New or old, railway sleepers are very strong, meaning that they will hold back the pressure of the water without bowing when joined with sealant, while also providing a formal, architectural wall for your raised pond.

New railway sleepers typically come in set lengths like 6’ and 3’, so it's easy to create a 6’x6’ pond with them, without any cutting, or a 6’x3’. Get creative and you could use a combination of 6’and 3’ railway sleepers to create an L-shaped pond. Other timber can be used for wooden ponds too, just make sure it's at least 2” thick to be strong enough to hold back the water without bending. 

Brick or block-built ponds are the ultimate raised garden ponds in strength and are the best if building a large koi pond. Concrete blocks can be rendered on the outside or a rustic brick can make a newly built raised pond look instantly aged. Any bricklayer will be able to build you a raised brick or block pond.

The creative pond builder can use any rigid structure in combination with a pond liner, to hold water, and then clad the outside with a covering of their choice. At the small end tractor tyres can be used, half barrels or bathtubs. Even a Belfast sink can be turned into a raised pond, albeit a small one.

IBCs are commercial water-holding vessels that are purpose-built and widely available. Euro pallet-sized plastic containers originally designed for holding fruit can also make a great basis for a cheap raised pond. They are tough and safe for use as fish ponds. They just need disguising on the outside.

Alternatively, you can select a pond from our range of pre-built or self-assembly feature ponds that require little work to be ready for use in your garden.

Getting started with raised garden ponds

The first thing to consider is placement. A raised pond should be near the house to take advantage of an outdoor socket (although remember that you will need to wire the plugs on many pond electricals) and even enable viewing from the house when you're inside. Great for cold winter days (when you might need to use a pond heater). Place a raised pond at the bottom of the garden and you won’t be able to see the fish from the house, nor will you want to cross a muddy lawn to inspect it in autumn and winter. 

Next, ensure the site is level. Use a long length of timber and a spirit level to level up the area across its length, width and diagonal. The great thing about a raised timber pond is that you can build the first layer from four sleepers in a square shape, for example, fasten them together and then raise the frame in one corner to get it perfectly level.

Use shims made from thin slivers of timber to get the frame perfectly level at the base, and then every layer on top of that will be level too. This is especially important with raised formal ponds as if the frame isn’t level, the water always will be, so there will be differing amounts of pond liner and frame exposed at one end to the other and it won’t look right.  

Rocks and roots puncture pond liners

Unless your proposed pond will have a solid concrete base, you’ll also need to prepare the base of the pond for pond liner just as you would for a standard in-ground pond. Clear the base of tree roots, sharp objects, rocks and stones and anything that could pierce the liner. Use pond liner underlay on the base and sides just as you would with other garden ponds.

Fastening railway sleepers together

The taller you build your raised pond, the more outward pressure the water will place on the perimeter. Sleepers should be fastened together with 90-degree angle brackets or if you’re handy with timber, coach bolts.

If you’re not using thick sleepers you could use vertical timber stakes or wooden fence posts in each of the four corners and then clad the timber frame around those, screwing the frame to the posts like you would with a raised vegetable bed. They’re built in exactly the same way. Make sure that no screw or nail tips are exposed which will puncture the liner. 

Ensure that every joint is sealed with pond paint or sealant to ensure that it is watertight, especially if the wood is irregularly shaped.

How to line a raised pond

Calculate the pond liner size by measuring the depth, doubling it, and adding that number to the length and width of the pond. So if the pond is 6’long by 6’ wide by 2’ high, double the depth to 4’ then add that to the 6’ in each direction. Give yourself a bit of an overhang at the top and you’ll need a liner which is about 12’x12’, or 4 metres by 4 metres in metric, and underlay to match. If you’re not sure about calculating your pond liner, check out our ready-made pond liner calculator.

Place the underlay in first then, using two people to carry the liner like you would a bedsheet, stretch it flat before loosely, and carefully draping it over the frame. Place a hosepipe in the pond as it starts to fill with water, and apply gentle pressure to each side of the liner to stretch it out and enable neat folds in the corners. Fill to the top.

Capping for raised ponds

The great thing about raised ponds is how easy it is to hide and disguise the liner at the top. With your pond filled the spare liner will be draped around the outside edges. Take another layer of sleepers to create one final frame on top of the liner, fit, and then trim the liner on the outsides of the pond.

If you are using any other timber frame, timber capping is available from timber merchants or DIY stores, and for brick, another layer of brick, small flags or concrete capping can be used. Fit the final capping layer then trim the exposed liner on the outside of the pond for a neat, professional-looking job. 

Raised pond filtration

If you want to add fish to your raised pond you’ll need some form of filtration. A pump, filter and UV clarifier will keep the water clear of debris, break down fish waste and clear green water, but you want a discrete filtration solution at the same time which won’t spoil your vista.

For small ponds of 1000 litres or less, an all-in-one pump, filter and UV is the neatest solution where everything is built into the pump unit and is placed in the middle of the pond. These compact filters will provide a decorative fountain or run water features too. 

For larger raised ponds the best solution is a pressurised filter with built-in UV. Unlike gravity-fed filters and black box filters, pressurised filters can be placed beneath the pond surface, behind the pond, or some distance away. They can even be buried up to their lids in the soil. Place a solids handling filter pump in the middle of the raised pond, run a hose to the filter, and then from the filter back to the pond. Many pressurised filters can also run dirty water to waste or a flowerbed when being cleaned.  

Once you have created the perfect raised pond, take a look at our range of outstanding pond plants to create a beautiful and vibrant water garden, we even offer baskets, soil and fertiliser so you can find everything you need.