How To Repair Pond Liner That Is Leaking

How To Repair Pond Liner That Is Leaking

Anthony Barnes

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A drop of water level in your pond can mean a lot of things, but the first you’d think of, and potentially the most problematic is there being  a hole or tear in the pond liner.

In this article we’ll be discussing this problem, and how you can go about fixing your pond liner in a few easy steps. So without further ado let’s get started.

But first, be sure to check that your liner is leaking, and nothing else is causing the water level in your pond (see also ‘The Ultimate Guide To Pond Water Level Control‘) to reduce.

Pond liners are expensive and tricky to work with, so it’s always a good idea to check for any other issues before you get started on this job. 

Is There A Leak In My Pond Liner?

The first thing to consider as we said above, is if the issue is directly related to your pond liner, and nothing else, so let’s take a look at some other potential issues you may have.

First off, evaporation of water is a consistent issue seen with ponds, especially in the warmer summer months of the year.

If you can see that your pond is slowly losing water over a matter of days, then it’s more than likely evaporation affecting your pool.

This is completely normal of course, and won’t be as large of an issue as if you had an actual leak in your pond liner.

Instead you can expect to lose around 1-2 inches of water per week if you’re seeing symptoms of evaporation, and you could quite happily top your pond off with some extra water, but usually this is naturally repaired with rainwater, and shouldn’t be too much to worry about.

However if you have a water feature in your pond and you’re experiencing some extreme heat, it’s not uncommon to see 8 inches of water loss every week instead, this alone is because of your water feature meaning there’s more surface area of water that’s exposed to air and heat, allowing for more evaporation to take place, your best bet is going to be to turn your water feature off during extremely warm days, or simply replace the pond water after a drastic loss. 

There’s other causes of water loss too, including objects blocking waterfalls you may have in your pond, leaks within your circulation system, and improperly installed water skimmers.

All of these issues are going to be easily fixed once you find them, it’s just important to thoroughly check all of your pond’s systems to see if any of these are the culprit. 

If there’s a leak in your pond liner, the loss of water from your pond should seem disastrous at the best of times.

You won’t see the same gradual water loss as you would from basic evaporation, but instead you’ll see a rapid and uneven dispersion of water flowing out of your pond, and into the soil below.

If you’ve read these above points and you’re certain that your issue is your pond liner leaking, then there’s a simple test you can do to be certain. Simply:

  • Fill your pond back up to an appropriate level
  • Unplug all pond equipment, including the pump.
  • Allow your pond to sit for a day
  • If you see a noticeably large difference in water quantity between these two days then you’re looking at a leak in your pond liner.

How To Locate Leaks In Your Pond Liner

So now that you know that you’ve got a leak in your pond liner, the next step is to locate where exactly your leak is coming from.

Pond liners can be large things, so being able to precisely pinpoint where your issue is is going to be an enormous help in repairing your pond.

The simplest, and probably easiest way to locate a leak in your pond liner is simply to let the water inside of the pond escape, until it stops.

This will allow you to see at what level exactly your leak is located, which makes it much easier to find it once you’re up close, if you’re having trouble finding the leak as it’s small, then look for where your water is flowing whilst it drains, or even small bubbles as the water escapes out of the leak. 

If you’re still having trouble after this, then you can add a small amount of condensed milk to the water, which is much clearer, and will allow you to see where exactly the water is flowing to whilst it drains from the pond.

Be sure to only use a small amount of milk though, and don’t worry, this much milk won’t affect the health of your pond in any way.

Some drawbacks to this method are notable though, if you have fish you’d be best holding them in another tank for a little while, as the leak could be on the bottom of your liner, meaning that the fish don’t have enough water to survive once you’ve located the leak.

As well as this, this method intentionally wastes a lot of water, as you’re essentially just emptying the contents of your pond out into your garden, so be prepared for some unwanted wet side effects. 

Repair, Or Replace My Liner?

Repair, Or Replace My Liner?

Once you’ve found your leak, you’ll probably be wondering if it’s best to try to repair the damage, or simply buy a new pond liner, whilst this will obviously be different with every leak, it’s good to generally consider that small tears in your liner are easily repairable, but larger holes inside of the liner are just going to break again, meaning you’re going to have to buy another pond liner.

Remember that these are expensive too, so if you can help it you’re probably going to want to repair your leak instead of replacing it. Below are some of the best methods you can use to repair your pond liner:

Pond Liner Kits

Best Used For Small To Medium Sized Leaks

Pros

  • Simple, all in one solution that you can easily apply to your liner
  • Really easily repairs smaller holes
  • Once settled it blends with the liner great, you’d never know you’d have a leak.

Cons

  • Not going to work for larger, more extensive damage done to your liner
  • Requires a dry application, so you’ll have to fully dry out your liner.

If you’ve got a small to medium leak in your liner then there’s really no better choice than a pond liner repair kit.

They’re relatively inexpensive and come with absolutely everything you need to repair your pond liner.

They also come with instructions so they’re perfect for inexperienced people wanting to save some money by repairing their liners instead of buying a whole new one.

Generally these kits come with a patch, which you can stick over the leak, after a little while the patch will be completely stuck to the liner with a waterproof seal.

After that it’s easy as giving your pond liner one more look over to inspect for any other forms of damage, and then getting it back in your pond. 

These patches can come in all sorts of measurements, all the way from 2×2 inches to 30×30 inches wide, and if you’ve got a larger patch then you can cut them down to fit the size of your leak, no waste! 

Make sure before you jump in though, check that the area with the leak is completely dry, and use the primer that’s included in the kit to ensure that the patch fully sticks to the liner.

Once your patch is attached you can use the roller to ensure that any air that was stuck inside of the patch is removed, so you can be sure that you won’t get another leak in the same spot again. To summarize in a few key points:

  • Cut a patch for the leak, circle shapes are the most durable
  • Locate the tear in the liner and clean the area with primer
  • Press the patch over the hole and hold firmly for a few seconds
  • Once rigid, roll over the patch with the included roller, and you’re good to go.

Pond Liner Joining Tape

Best Used For Fixing Leaks Where Extra Pond Lining Is Needed

Pros

  • Great for when you have a leak at the top of your liner, where having extra pond lining would be useful
  • Can be used for general small repairs elsewhere
  • Good for sealing anything you may have inside of your pond, such as a pond skimmer box

Cons

  • Not designed for sealing larger tears or rips.
  • Can be difficult to apply, you probably need 2 people
  • Both sides of the tape are sticky, resulting in debris collecting in an undesired location

Pond liner joining tape is useful for niche scenarios but it does repair them extremely well.

If you have a leak in the top of your pond, or just have a lack of pond liner, you can use the tape to fill out any leaks that you might have.

It’s as simple as priming the two surfaces you’re joining, and applying the tape to the edge of your liner, or over any smaller leaks that you might have inside the liner itself.

The tape is durable, and will last a long time without any fuss, but it’s not going to be effective at anything much larger than a small tear.

The joining tape is also great at providing more liner for equipment that hasn’t been setup too well, simply apply it in the same way you’d apply it anywhere else and you can fix any equipment you may have in your pond easily. 

Pond Liner Repair Sealants 

Pond Liner Repair Sealants 

Great For Very Small Holes And Rips In Your Liner

Pros

  • Really effective at filling in small holes and rips
  • Cheap!
  • Really easy to do

Cons

  • Not as durable as the patches
  • Takes a long time to fully set whilst being completely dry
  • Will only work on very small leaks.

If you didn’t want to use patches, then your next port of call would be Pond liner repair sealant, as it’s the most cost effective method on our list, and is great for filling in tiny leaks, up to around 2 inches in diameter.

To use the sealant, you need to drain the pond (see guide on how to drain a garden pond) and make sure your leak is completely dry, then apply the sealant directly to the tear using the nozzle on the can that you’re using.

You’ll have to wait up to 8 hours for the sealant to gradually cure, and fill the hole that you’re covering, but after that time you’ll be delighted at its waterproof and durable qualities, with it being so easy to do. 

You’d be surprised that the sealant is completely fish and plant friendly, and won’t do any harm to them whatsoever, and it can be used for all sorts of problems you might have with your pond.

If you need extra lining on a waterfall or fountain, simply apply it and wait.

Repair sealant is convenient and so simple, you’ll be surprised at how effective it is with very little effort!

Replacing Your Pond Liner

Your Only Option For Large Tears, Or Rips In Your Pond Liner

Pros

  • From all of these options, this is the only option that will truly last the longest, a brand new high quality liner can last up to 25+ years, and won’t let you down.
  • Best and essentially only solution for larger holes in your pond liner
  • If you replace your pond liner you can be certain that no other issues remain.

Cons

  • The most expensive solution to your leaking problem
  • Requires the most work, as you’ll have to drain and empty your pond and start again from scratch.
  • Completely overkill for anything smaller than a large leak. Don’t replace your pond liner unless it’s a large leak!

If you’d just prefer a fresh start, or have a leak that’s too large to fix, then simply buying a replacement pond liner is going to be your best option.

But bear in mind that if you have small rips or tears in your lining then there’s absolutely no need to replace your entire pond lining at all, just choose some of the options above and you’ll save yourself money and the time and effort it takes to replace an entire pond liner. 

When purchasing a new pond liner you should consider what type of material you’re going for.

There’s loads of options available to you so you should consider all of the advantages and disadvantages that come with the many different materials, but in general, rubber based liners are going to withstand tears and general damage that’s done over the years you’ll own it.

PVC and LPDE are also options that you can take a look at, which add a lot of flexibility to your pond, which may be an advantage if you can see yourself doing a lot of work with it over the years.

HPDE is also a great choice due to its resilience to chemicals, and can last upwards of 36 years if treated right, so there’s loads of options you can choose from. 

Whatever your choice, buying an all new pond liner can be an expensive and critical decision for the longevity of your pond, so make sure you research the materials properly, and make the decision that suits your needs best.

Preventing Pond Liner Leaks

The main issue that lies with pond liner leaks and tears is that it’s really hard to work out what caused them.

Due to most pond liners nowadays being durable and able to withstand a good amount of pressure, usually if a pond liner tears it’s because of some foreign entity that’s pierced through the liner itself, or it’s just exceeded its best of date.

Because of this, it’s really hard to tell what specifically breaks pond liners, but it’s important to try and understand how it broke so that it doesn’t happen again.

Below are some common reasons as to why pond liners break, and solutions to stop it from happening ever again.

Add Netting To Your Pond

A relatively cheap and simple way to increase the durability of your pond is by adding high quality netting to the surface of your pond.

This reduces the amount of debris that can fall in your pond, which reduces the overall sludge that builds up in your pond over time, this sludge if left unattended will build up over time no matter how great your netting is, and things like sharp sticks and stones will eventually cause damage to your pond lining.

By adding a net though you can reduce this amount of buildup massively.

As well as this nets stop predators from attacking your fish from the pond’s edge, as birds such as herons do.

Herons are large predatory birds that will attempt to catch fish from your pond with their sharp beaks, as you could imagine this can cause huge damage to your pond, as well as being a large reason why holes are poked in your netting.

By adding a net the herons cannot poke through to the water anymore, so don’t bother going near your pond. 

Nets are extremely cheap but you can really see the difference that they make. If you don’t have netting over your pond i’d strongly suggest getting some as soon as possible.

Remove Sharp Stones From Around Your Pond

Many people choose to decorate their pond with stones around the edge of the water.

Whilst this looks great, sharp stones can be knocked from their places into the water, or the pond lining, which can easily puncture it, resulting in a leak.

Even if stones are directly inside of the pond, they will sink to the bottom and scrape along the pond floor, which over time will wear down the lining of your pond.

Instead look for rounded, smooth stones to line your pond, and if you see any that have fallen in, just net them out to remove the risk of punctures.

Use Underliner

Pond underliner is a great way to add some reinforcement to your pond, without compromising the look of it.

Underliner is similar to lining, but goes underneath it, and is much more flexible whilst retaining a lot of that durability.

It cushions the pond liner from both sides, and really reduces the risk of leaks due to all of the extra durability that it adds.

If you’re choosing to replace your pond liner it’s a great idea to purchase a good quality pond underliner that you can wrap around your liner.

It’ll increase the longevity of your liner, stop punctures, and do both of those things without looking any different from above. Underliner is a great way to buff up your pond!

Ensure That Your Liner Is Secure Around The Edges

Your pond liner is most fragile around the top of your pond, usually where you disguise it with stones or plants.

So make sure that all of the top of your liner is completely secured, that can be with stones, plants or anything that suits your garden, you’ll reduce the risk of the top of your liner tearing if you keep it secured behind another strong surface, and if you need anymore of it added, simply use joining tape to add more.

Final Thoughts

Pond lining nowadays is not a fragile thing, new liners are incredibly durable, and can last decades long.

But that doesn’t mean that things don’t go wrong, so just in case that they do you can always come back to this guide to find a solution to your problems.

Remember that every pond is different, and you’ll prioritize different things for your own pond, so be sure to do research before you buy anything! 

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By Anthony Barnes

Anthony Barnes is the founder of Water Heater Hub and a second-generation plumber by profession. Before developing Water Heater Hub, Anthony Barnes was a full-time plumber, and he has undertaken a wide variety of projects over the decades. As a second-generation plumber, it was easy for Anthony to get used to the technicalities of all from a tender age