Newbie—is a liner always necessary?

[Rebecca]

Hi everyone. Boy am I glad to find this site!

We bought a house two years ago with a tiny backyard and a pretty big pond/waterfall. Of course it leaked. We had someone who turned out to be pretty unknowing themselves put in a liner, which it didn’t have, but it didn’t solve the problem, was too high onto the rocks, and was ugly as sin. My husband eventually found that painting the underside of the slate shelf that the water ran off of at the top with water repellant helped a lot, as water was running back under into the rocks.

That liner has been a pain—ugly, floating, not well trimmed, etc. And the big pool seems to hold water without it. My question, do we need it? As I read everyone seems to have one. What is the upside?
Thanks in advance. I’m looking forward to some wisdom in many areas!

 

[j.w]

@Rebecca
What is your pond made of, concrete, clay or? We that have liners usually have them cuz our land is dirt that won't hold water. If you have concrete that cracked perhaps someone here can help w/a sealer. If your pond is clay and held water and now it does not I'm not sure if there is a fix other than adding more clay.

 

[Rebecca]

Thanks for the reply. It’s concrete, is about eight years old, and right now the lower lever seems to be holding water w/o the liner. We’re going to test the upper.

We might want to put sealer in anyway just to be safe. Suggestions for sealers?

 

[Mmathis]

Hello and welcome!

Why not post some pictures of the pond so we can see what it looks like. No, you don’t have to have “a liner” as such, but you do need a way for it to hold water. Concrete (I believe) has to be sealed. Most of us use an EPDM rubber liner (stay away from “plastic” or PVC). Yes, a liner can look like crap (if not planned for and/or installed incorrectly), but there are lots and lots of creative ways to get around that!

Again, post a bunch of pictures for us, and I’m sure we can help you around this!

 

[Rebecca]

Thanks. I’ll do that but it might be a couple of days. Right now the lower oil is full of water and we’re about to test the upper to see if it leaks. I imagine photos with them empty will be far more helpful. We’re just north of Seattle and though there seem to be a fair number of water features around finding someone who’s good at doing work is proving hard, not to mention that year-long break in having people willing. It’s better now, but we’re thinking we can handle it. With good advise.

 

[Rebecca]

*pool* not oil.

 

[brokensword]

*pool* not oil.

don'tcha just love spell correct?

If your ponds are concrete and leaking, imo, I'd not bother with trying to seal. The ground shifts and over time, you get cracks, unless the concrete was put in correctly. Even then, mother nature will do her best to crack it. Imo, it's a lot less hassle and sure fire way to satisfaction if you just line it and figure out how to conceal the overlap on the sides. Pics would help the the basic idea is you'd dig/lay a row of wood/cinder blocks as a top layer on the ground, place your liner under and up the back of this new layer. Then you landscape behind and on this new layer, you'd put your trim rocks. You then fill the pond to halfway up these new trim rocks and voila! your liner is covered. For your waterfall, similar in that you'd put this liner in a bowl shape, up the sides and up the back of your rock waterfall, to catch all and any water that doesn't go where you want.

With a liner, you'll get 20+ years of peaceful bliss. Fixing cracks and sealing, maybe 5 or more, you just can't be sure like you can with a liner.

 

[GBBUDD]

Most concrete ponds are built by weekend warrior's. I believe just about everyone has seen how a concrete pool is built.. lots of rebar gunter skimmed with plaster.. This type of design can last 50 years. Without issue.


Now the weekend warrior's ponds with little to no rebar or compaction can get ten years before something shifts or the plaster or top coat starts to fail.

Waterfalls unfortunately untill recently have usualy looked like a man made stack of rocks trying to direct water down a volcano..

Let's say you want a 4 foot wide with a 4 foot drop that is going to splash water as far as 8 feet from the base of the falls . This will require your sides to control this splash or your pond being wide enough to catch it.
Most build there waterfall as the highest point to the area you never see where the waterfall is on the outside edges and the earth wraps backwards. Mother nature cuts her way into the hill side and those sides control the water. Thats where the liner or concrete has to encompass this area. The falls to the pond it's self is easily controlled by overlapping the liner into the pond.

Wicking is also a big concern to keep in mind that is where your liner is folded over and water can actually get pulled up a inch or two like someone sucking on a straw. Plants can do the same as they can be hollow and as crazy as it sounds water can travel upward without and power source.

 

[poconojoe]

As stated, there are so many ways to conceal a liner. So, don't go through all the work of emptying the pond to remove it until we see what you have.
We can suggest some ideas if you throw up some pictures.
One tip: don't cut off any excess liner material unless you have a ridiculous amount of extra. Fold it up and tuck it under rocks, soil, whatever. You never know when you might need an extra bit of liner and if it's cut too short you'll have a problem. Liners can settle with the weight of the water or you might want a little extra liner to create a different shape or look to the edges.

 

[zeuspaul]

My first choice is well built concrete without a sealer. Mine is made of filled block with rebar. It has Rapid Set mortar applied with a trowel for water proofing. It is ten years old with no problems. Rapid Set is not portland cement based but sticks well to the block. If necessary I can clean the surface and add a coat as necessary which I have not yet had to do. If I applied some kind of paint sealer this would be difficult. Concrete is permanent and difficult to modify.

My second choice is my preformed ponds. They have held up well over time. They have steep slick edges which has caused a lot of death to my native lizards. I have found ways to minimize this.

My last choice is a liner. They have not held up well over time. I have had problems with critters damaging the liners. I know liners are a first choice on this forum. My experience has been different. Certainly they are best in some situations. My primary concern is a permanent solution.

 

[poconojoe]

My first choice is well built concrete without a sealer. Mine is made of filled block with rebar. It has Rapid Set mortar applied with a trowel for water proofing. It is ten years old with no problems. Rapid Set is not portland cement based but sticks well to the block. If necessary I can clean the surface and add a coat as necessary which I have not yet had to do. If I applied some kind of paint sealer this would be difficult. Concrete is permanent and difficult to modify.

My second choice is my preformed ponds. They have held up well over time. They have steep slick edges which has caused a lot of death to my native lizards. I have found ways to minimize this.

My last choice is a liner. They have not held up well over time. I have had problems with critters damaging the liners. I know liners are a first choice on this forum. My experience has been different. Certainly they are best in some situations. My primary concern is a permanent solution.

As always, it's a personal decision.

If you choose the right liner material and it's installed correctly, it will last a couple of decades. 45 mil EPDM is a thick and pretty tough material.
You can design your pond perimeter to prevent critters that may wreak havoc by entering the pond.

Concrete or block and concrete are more of a permanent design which may deter some homeowners from going that route. If you decide down the road that you no longer want a pond, now you have this concrete structure to deal with. A liner can be pulled out and the hole can be filled quite easily.

Then there's the sealing of the concrete. There have been many posts here on that subject. Many people struggling to do this.
However, it appears you have found the solution to that problem. That's your contribution to this forum and we thank you for posting your experience.

Something I heard many times on jobsites...
There are two types of concrete, one that's cracking and one that's going to crack. It takes something like 100 years for concrete to fully cure.

Performs can be a pain. They have to be absolutely level or you'll see that ugly black plastic on the side that is too high. With a flexible liner, you can create a very shallow shelf all around the pond, place stones half submerged there and you'll never see the liner.

Preforms can also shift as they settle or if your ground is not that solid.

Preforms are limited in size too. If you want a 2,000 gallon pond, I don't think you can get a preform that large.

So, whatever makes you happy or works for you. Everyone is different.

Various opinions and experiences will help others decide what's best for them.

 

[zeuspaul]

@poconojoe I was commenting on the OP's statement that everyone seems to have a liner. The OP already has a concrete pond that is holding water I don't see a need for a liner.

In my case my liner pond suffered a racoon attack. The concrete and preforms given the same conditions have held up well. My ponds are primarily for native frogs and I have no need for a large pond or which I agree would be better for large ponds or concrete if a permanent pond was desired.

There are two types of liners, one that's leaking and one that's going to leak.

I agree with just about everything you posted except the 100 year curing time for concrete. It is true that concrete continues to cure for long after it has reached design strength for even more than 100 years. The strength it achieves after 28 days which is the time for normal concrete to cure to design strength is insignificant wrt to ponds and just about anything else.

 

[poconojoe]

@poconojoe I was commenting on the OP's statement that everyone seems to have a liner. The OP already has a concrete pond that is holding water I don't see a need for a liner.

In my case my liner pond suffered a racoon attack. The concrete and preforms given the same conditions have held up well. My ponds are primarily for native frogs and I have no need for a large pond or which I agree would be better for large ponds or concrete if a permanent pond was desired.

There are two types of liners, one that's leaking and one that's going to leak.

I agree with just about everything you posted except the 100 year curing time for concrete. It is true that concrete continues to cure for long after it has reached design strength for even more than 100 years. The strength it achieves after 28 days which is the time for normal concrete to cure to design strength is insignificant wrt to ponds and just about anything else.

Good points.

I can especially see your point about critters damaging your liner as your reason for concrete preference.

Everyone's situation is different. That's what makes the world go 'round, as they say.

And it's great that we have a few choices for holding water in our ponds.

I only meant that concrete continues to cure for a very long time. 100 years is what heard.