EPDM Liner question

[WaterLilly]

Hey guys,

We will dig a large pond.

Dimensions : 30 ft to 15 ft .
Estimated total volume 35k gals.

We will put some rocks on the edges in time but we can't afford some nice ones yet. We don't want to rush and put some bad looking ones now.

My question is , if we don't place rocks at the edges, do you think the EPDM will be pulled in by the weight of the water? Or should we at least put some bricks to hold it?

I don't want to do anything dangerous. A friend suggested me to have 4-5 ft extensions on the edges of EPDM and dig it in the soil.

Not sure.

 

[morewater]

Pond edges are one of the most prone areas to unprofessional finishes and will stand out like a sore thumb.

A rock edge should be partially submerged in order to hide the liner. No liner should show in a professionally-built pond.

Incorporate a shallow, wide shelf around the perimeter of the pond on which to place your perimeter stones. In this manner, the stones will be partially submerged, and partially below the ground surrounding the pond.

Excess liner is simply folded up, pushed up against the back side of the perimeter stone and then backfilled with pea gravel, soil, mulch, whatever.

EPDM won't be "pulled" in by the weight of the water without a perimeter, but will be prone to allowing water to seep under the liner, creating a "hippo".

When you're laying your liner, simply pull it over the excavation, start filling it with water and allow the weight of the water to "pull" the liner into the hole. The liner can be manipulated for quite a while as it fills. This timeframe allows for the "pleating", getting the liner just right, etc.

Line your excavation prior to putting the liner in. Use old carpet, geotextile, whatever as long as it won't disintegrate over time.

Lay your liner out in the sun for a while to "soften" up. They're easier to manipulate when warmed up. For a liner of that size you should have at least three people around. For a liner of that size, hell, you might as well call in a water truck to fill it. It'll take forever with a garden hose and if you feed the three adults beer while it fills, you'll never get anything done (I volunteer, simply send air fare).

Good luck, don't be in a hurry.............

 

[EricV]

Remember, rocks you put in the pond are going to be covered in algae and what-not almost immediately, so go ahead and use cheap, ugly ones for anything that will be submerged. I guess you should stay away from large amounts of limestone to avoid changing the water chemistry too much.

 

[WaterLilly]

Thanks for the very useful info. As a beginner it is good to know all these.

I will have 3 levels.

Level 1 - Perimeter - 10 inches deep - 15 or 25 inches wide
Level 2 - Waterlily pots - Same depth and wideness as level 1
Level 3 - Deepest level


What's the deepest i can go for waterlily pots level?


Can someone please help me understand why in the instructive videos they don't make a perimeter level all around the pond but at some parts of it? As you said if there is no perimeter, the liner will look ugly.

Ty.

 

[mrsclem]

I have some of my lilies at 4 1/2 feet. As long as they get sunlight but check the variety you are planning on. Each one is different. Your liner will get covered with algae over time.

 

[morewater]

As to the perimeter "all around the pond", I stated that a narrow shelf was all that was necessary to hide the liner so that the perimeter rocks rest on the shallow shelf just enough to submerge the perimeter stones.

As to water lilies, most prefer the upper range of the pond. I've seen them growing in water as shallow as 18", but really do think that 2.5-3' is the ideal depth.

Should you wish to have lilies in the deeper part of the pond, this can be accomplished by using milk crates topped with large pieces of flagstone on which to place the pots. These structures provide a hiding spot for the fish as well as raising the lily pots closer to the surface.

In colder climates, it's then easy to simply pick up the pots and lower them to the bottom of the pond for the duration of the winter.

Remember that lilies will do best if fertilized annually with a slow-release aquatic fertilizer.

 

[CometKeith]

Be sure to raise the edges of your pond up otherwise ground water will seep into it with unwanted consequences.

 

[snoozer]

Make your top shelf the 25 inches wide or more. Mine is 24-36 inches and 12 inches deep. The large rocks, the ones that needed the assistance of a skid loader to move are on this shelf. I filled between the boulders with small stone to keep them stable. Smaller various size rocks are on top of these. I will see if I can find a picture to post tomorrow.

 

[Mmathis]

Hello and welcome!

Despite what the instructional videos say....... You can put a shelf all the way around on the the top level. It's really personal preference more than anything. Mine is like that, and it makes it look more natural. I only have that one shelf. And I don't use pots -- I stick my plants bare root in among the edge rocks. They do just fine for my location. My lily pots sit on crates in the pond so I can adjust the depth to suit the plant. As @morewater mentioned, though, if you are in a colder climate, having all your plants in pots is helpful for setting them in deeper water in winter. It's all personal preference more than it is a rule.

 

[Timothy]

Are you anticipating a 10' deep pond? I only mention this because of your perimeter dimensions and estimated gallons. This depth may require a different approach to the sides. To get that many gallons in a 35'X15' perimeter the sides would have to be straight down.

 

[WaterLilly]

Thank you all. Getting to a point already.

I am sorry i am not able respond all because i am in a great rush. Tomorrow this thing has to be done but i read all of them and have been applying all to my project.

This is my new thread. I got some very painful questions . Please check .

https://www.gardenpondforum.com/threads/in-trouble-with-excavation.19946/




Timothy my numbers are not very precise. Maybe i won't achieve that volume.

 

[Mmathis]

@WaterLilly I just read your other thread -- thanks for the link. But I'm having trouble grasping the size.....and your questions. OK, if I have all this wrong, please excuse this post......

I know you're planning on a deep end and a shallow end, is that correct? So about 30 feet long and 15 feet wide, and 9-10 feet deep in the deepest end; 15 inches deep in the shallow end..... Are your sides going to be dirt, or are they going to be reinforced with concrete blocks? Why so deep (just my own curiosity) and how much of the total pond will be that deep?

You mentioned a lot of sharp rocks in the way. Can those be removed with the excavator?

Compacting the dirt around the edges would be a good idea, you can use the excavator for that -- use the bucket to pound with.

If you mean compacting the bottom, no because the weight of the water will do that.

If you are going for dirt sides, if it was me, I would slope the sides instead of having them go straight down. My experience with deep+straight has been that the walls have collapsed.

And what you do to achieve the shelves is is dig like this:

 

[WaterLilly]

Mmathis, it is a bloody good idea to have a slope. I will answer the rest of it on the other thread.

 

[Becky]

Link to parallel topic: https://www.gardenpondforum.com/threads/in-trouble-with-excavation.19946/