7 Steps To Install A Pond Liner In A Square Pond

How To Install A Pond Liner In A Square Pond

A pond is technically any body of water smaller than a lake, and it can be natural or artificial, permanent or temporary. The temporary ponds are called vernal, but your backyard pond is more of a permanent fixture.

Building a water feature is relaxing, and it’s a great way to cool down your space naturally, but how do you install a pond liner in a square pond? I’ll walk you through the process step by step, so your pond won’t leak.

You can easily install a pond liner in a square pond by choosing the right, appropriately sized square liner. Placing it evenly and then filling the pond is relatively straightforward, though it does require attention to detail. The hardest part about installing the liner in a square pond is smoothing out the wrinkles on the sides.

How To Install A Pond Liner In A Square Pond

Installing a pond liner, regardless of the shape, isn’t difficult. Choosing the right shape and size is essential, but once you have the materials you need, it’s a reasonably quick process.

Follow the steps outlined below to install a pond liner in a square pond.

1. Prepare The Area

Digging a pond is relatively simple. You can hire a professional or opt to DIY, but either way, digging is easy unless you’re trying for a tiered, step-down effect inside the pond.

Regardless of style, the most important thing is to ensure that the lip of your pond is level on all sides.

A level bottom looks nice but isn’t necessary. Moreover, once you backfill the base and add your liner, it can help even things out.

However, if one side of your square pond is lower than the others, you’ll have issues with spillage constantly channeling the same direction. This can lead to soil erosion and other problems.

If you need it, a firm, straight board that will lay across the pond from side to side without bending and a carpenter’s level can help you ensure that everything checks out.

Unfortunately, this isn’t a perfect method. A laser level is a superior tool for checking that your pond has even sides.

Since these clever levels use light to measure for you, there’s little question of human error. Laser levels are point and click.

2. Lay Sand

You should allow six to eighteen inches of additional depth for your sand layer on the bottom of a pond. The sand creates a smooth, load-bearing surface.

More importantly, it doesn’t have sharp edges that can puncture our liner, causing leaks.

According to BTLiners, “When considering the type of material necessary, rubbers like PVC and EPDM always require underlayment in their application, whereas RPP and RPE do not.

Choosing a pond liner known for its strength, durability, and puncture resistance can eliminate another costly layer when building your pond.”

Choose either beach sand or mortar sand for the bottom of your pond and get enough for an even layer across the entire bed.

Once your sand is laid, it’s a good idea to treat it with an antifungal spray. By doing this, you can help prevent moisture from the pond or rain from creating a layer of biologically active and potentially toxic material under your water feature.

3. Choose Your Liner

You have two basic choices for a square pond.

First, you can opt for a custom-fitted square liner. Several private companies make custom pond liners.

Secondly, you can choose an oversized liner in any shape and fold it at the corners to fit your space.

The material of your liner also matters. EPDM and PVC are also known for their flexibility, and these materials fold around corners easily.

PVC is also the most cost-effective. However, PVC is often treated with chemicals that can leech toxins into your pond water.

Meanwhile, reinforced polypropylene (RPP) or reinforced polyethylene (RPE) are both highly puncture resistant. EPDM is the best general liner for square ponds, but your circumstances, climate, and specific needs may vary.

When in doubt, consult a professional for advice on your particular pond.

4. Set Your Liner In Place

Working from one side, roll your liner out across the pond. Then go around and even out the edges, so it overlaps roughly the same distance on all sides.

It’s okay if you’re off by an inch or two, so long as the liner overlaps the edges. This is the time to fold your corners neatly.

While the liner should generally be sitting on the bottom of the pond, you don’t need a perfect fit yet.

Another way to line your pond is to fold the liner in half and center it precisely. This method works well on smaller ponds where the overlap is less.

Once you have the folded liner covering exactly half your pond, lift the folded half, weigh down the side that’s in place, and unfold the liner to cover the other side.

Once the liner is in place, adjust any spots that need to be folded. Finally, you should use sandbags or heavy stones to weigh down the edges of the liner and hold it in place.

5. Partial Fill

The next step is one of the easiest. Unless you plan to haul water by hand or you’ve installed a water line, it’s time to hook up your hose and drag it over to the pond.

Put a few inches of water in the bottom of your pond liner.

Doing this will put pressure on the liner and force it to fit the shape of your pond but leave you room to smooth the bottom.

If there’s any air trapped underneath bubbling the liner up, you’ll want to push it out to the side so it can disburse.

Check the bottom of the inside edges of the pond and smooth out any wrinkles that are beginning to form.

6. Fill and Smooth

Filling the rest of your pond is a matter of patience. Fortunately, you can occupy some of your time adjusting the fit of your liner to smooth out any wrinkles.

Once the pond is full you won’t be able to move the liner again, so it’s best to smooth the edges manually as you go.

7. Cover The Liner

Gravel is a common way to cover your square pond liner. It’s important not to leave the overlapping edges exposed.

However, you can also pave around your pond if you prefer a nice, finished, and decidedly human-made look.

Once you’ve finished the edges, you only need to install your pump and add any plants or fish you planned for the space.

Helpful Tips To Know About Installing A Pond Liner In A Square Pond

The nice thing about lining a square pond is that it’s only a few folds different from lining a circular or irregular pond. The process is the same unless you get a custom-fitted liner.

Even then, a custom liner follows the same installation steps, but the difference is that it is made for your exact dimensions.

Here are more helpful tips to know about installing a pond liner in a square pond.

  • Always inspect your liner before you place it. A pond liner that has damage won’t hold water properly, and you’ll end up with a leak.
  • Ensure that you place your pond in an intelligent location. Some shade is a good idea, but a pond needs about five to six hours per day of direct sunlight if you want fish or plants to thrive. However, too much sunlight will encourage algae.
  • For an excellent example of how to fold the corners of a square pond liner, check out this video on boxing the corners of a tablecloth. All you need do is reverse the process, so it’s upside down.

Final Thoughts

Ponds bring a lot of visual interest and benefits to your space. They can up the property value and help keep your temperatures lower in that area through evaporation.

Additionally, growing water plants or keeping fish can be a fantastic way to create a unique feature. So long as your pond has an undamaged liner, it won’t leak water, which will ultimately save you money on your water bill and prevent damage to the pond itself.

Fortunately, installing a pond liner in a square pond isn’t complicated. In fact, if more people knew how easy it is, there would be more private ponds.

The most challenging parts of pond making are pump installation and keeping it clean, but placing the liner is merely a matter of patience.

Drew Thomas

My name is Drew Thomas and I’m the creator of Fun In the Yard, your one stop site for all your outdoor games, sports, party activities, outdoor gear, and lawn & gardening tips.

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