New Pond Construction

[Taneli]

Hi Everyone, I stumbled across this forum when researching about liners. I have built a couple of pondless water features in my lifetime and some small ponds but this will be the first for myself. So I got a couple of questions/throwing what i plan to do out there in hopes somebody corrects me if im way off base

1) I have only installed EPDM 45 mil liners in the past. Im about to bite the bullet on buying some HDRPE liner from American Tiliapia. I plan to line the entire pond with a mix of boulders and staked stone walls. I also plan to use and underlayment probably 2 layers (underlayment,liner,underlayment) its cheap enough. Is this a good idea or should i stick with the old EPDM.

2) Pond is dug to a kidney bean shape. Its 10x18 with depth of 32 inches. I have a 30 inch tall waterfall area with an 18 foot stream into the pond. I now want to add a bog. I love a high flow waterfall was planning on using a 8000gph pump. Now the problem is it would be to powerful for the bog i am assuming. I have attached the design with two proposed bogs. Bog 1 lets call it will be bottom feed from 8000GPh pump in skimmer and Wye it be top feed as well to give me desired flow. Bog 2 i can buy a larger liner and have it off to the side that would have its own little low flow water fall back to pond. It would need a seperate pump for that thinking 2-3000GPH. Which one would be more effective at filtration. Im leaning towards Bog 2

3) im located in pennsylvania and our boulders are primarly limestone. Has anybody had a problem balancing ph with lime leaching from the boulders?

 

[Taneli]

Opps forgot question 4. I plan for my stream to be a depth of 6 inches, 1.5-3 feet wide, and have a pitch of 2 inches in 18feet .is that sufficient or will it be to shallow and over flow

 

[GBBUDD]

underlayment,liner,underlayment) its cheap enough. Is this a good idea or should i stick with the old EPDM .............

We have members who have had luck with both and members who have had issues with both.

EPDM IS FAR MORE FORGIVING AS FAR AS MAKING BENDS. like a 90 degree though i recommend pretty much never doing so without slack. so if the ground should compact or move due to water channeling under the liner you need to have enough material to have give and not rip or tear. Pretty much the same thing for hdrpe but it does not like to bend as easily .

If your building a farm pond hdrpe would be my choice it's much lighter than epdm . However what i'm not sold on so much with the hdrpe is there are literally millions of points that can fail it's basically a woven material impregnated to make it waterproof. while rubber can cut very easily hdrpe not so much .

They say you don't need fabric under or over it i say its cheap or relatively cheap insurance. Heck of a lot cheaper to add it then it is to rip appart all your hard work placing stones looking for a leak . if you have nothing but clay or sand i still would add it as there's very little earth in populated areas where the soils haven't already been disturbed at some point , and you never know what just past what you see. Like myself I ran into the old construction dump site every home had one prior to the 70's TONS OF WHISKEY FLASKS glass bottles . metal buckets nails etc. i recommend a 8 oz fabric as a good base if you have lots of sharp rocks that would be my choice or thicker like 12 oz now that stuff is crazy tuff.

2) Pond

Your pretty close to what i built , very close i suggest you give aa read to my show case it may help you avoid a costly mistake or over look something . it's a lessons learned. it is long but there are all kinds of tips throughout first half is just the individual areas explained. the second half is the actual building . https://www.gardenpondforum.com/showcase/12-000-gallon-koi-pond-full-build.141/

limestone

Aquascapes uses primarily weathered lime stone now not all lime stone is created equal while some is crazy soft and some is as hard as the best of them.

 

[GBBUDD]

TO CRITIQUE the pond your sitting area is along side the bog making the waterfall a little hard to see as its sideway to the patio but head on to the fire pit. i would place the bog where you have 10'-3" labeled that way your main waterfall is looking at the patio further away so the volume is not so much you need to yell to talk.

HANDS DOWN I WOULD MAKE THE STREAM PART OF THE POND . its very cool watching the fish swim away and come fly down stream swimming with or against the current. if you only have two inches of pitch than i would have a second drop like 5 to 8 feet away from the falls making a small pool where watching the current drop the 2 inches at once is entertaining in its self.

As far as 6 inches deep i would think that is too shallow yes. mine is a foot in the middle less on the sides and i wish i had made it all 20" deep or so. my stream is my Achilles heel its the one part im not real happy with. i have to find just the right plant or no plants in the stream may be my best solution. I have videos of my build in that blog you'll see what i mean. don't forget a 3 foot wide excavation when it is rocked in is MAYBE 2 feet wide at best and 6 inches deep with gravel is 5 inches

i would look at how modern design aquascaping builds their bog at the surface the let the liner widen larger that the actual bog so they can decorate the bog with boulders and such and no cover the bog.

i imagine you have been watching the you tube videos for ideas i put these videos together for inspiration not so much for the whole build but to take a little of this and a little of that and combine to make your own.

 

[GBBUDD]

Again similar builds but instead of the second bog you can use that extra hp to have a return jet for circulation to the pond.

Lastly 8000 might sound like a lot of water it's really not that much i have a 12000 1 hp pump and with the head loss im probably close to 8000 my recent build of a bakki shower has added more head pressure than i'd like.

What I would also suggest is looking at an intake bay . they can be very handy and you'll never loose a fish in one. and they keep the pond free of leaves

 

[j.w]

@Taneli

 

[combatwombat]

Welcome. I've purchased and installed 3 liners equalling about 5,000 ft2 of hdrpe from American Tilapia in 2020 and 2021. They're tough as hell, but hard to shape to an intricate excavation. I had seepage issues. Where the liner received a lot of traffic around the edges during construction, I had to patch many very small leaks. That said, the sum of the volume of water lost appears to be not a lot more than I could estimate for evaporation. This summer will tell me if the remaining micro-leaks have plugged themselves with sediment as the owner of American Tilapia suggested they would.

By the way, HDRPE is marketing. It's just HD in front of RPE, which several manufacturers sell. The others are all HD as well, they just don't call it that.

I've seen it mentioned on other forums that RPE is more puncture resistant than EPDM, but that it is less abrasion resistant. That rings true with me. It's much harder to poke a knife through it, but if you drag your feet across it a million times over soil with tiny little pebbles in it (my situation) you might end up with some issues.

All in all, I'm pro RPE for the right projects, but wouldn't buy it from American Tilapia again. I'm in the PNW, so I would go with BTL liners. There are others you can choose from. But you might also be better off sticking with EPDM.

As for your 8000 gph into the bog, that is easily fixed by teeing off ahead of the bog and dumping out what you don't want flowing through the bog on top of it.. That way you get the ideal flow for filtration and still get the big waterfall you want.

 

[Hound Heaven]

Looks very ambitious and interesting. And you've gotten some great advice so far - these guys have tons of experience.
FWIW from an old person: you have the equipment --- use it to dig your pond a little deeper especially if your going to rock it.
Bogs are so fun to plant - you can try so many things and they'll all help to filter your pond. This was my go-to article for bog building: https://www.gardenpondforum.com/thr...upflow-filter-eco-filter-wetland-filter.6894/
I used hdrpe this time and it is less agreeable to contours but it is lighter.
One last tidbit - Mosquito Dunks work great and are safe for dogs. Oh and hydrogen peroxide really does help with string algae

Welcome!

 

[addy1]

Bend tarp and liner, in oregon, now makes a epdm type liner. For the past 3 ponds I have used their RPE. I have had deer stuck in the pond digging in with those sharp lil hooves, walknig in our stream, something on the edge left a lot of claw marks trying to get out. Never , yet, have had a leak. That stuff is tough.
Yes hard to shape, but check them out, esp with their new like epdm liner. I am thrilled with the company.

AquaProFlex - Pond Liner

www.btlliners.com

 

[Taneli]

Wow thank you so much for the responses and the copious amount of information thrown my way. So after some research im definitely going to build and intake bay versus using a traditional skimmer, now to decide on a submersible or external pump. or a combination of both if supplying bog with separate pump.

GBBUDD i love you idea of making a deeper stream that the fish can actually swim against the current. I was going to have a 6 inch fall after the stream into the pond but am now thinking of making more like 15-20 inches deep the whole way.

Part of the idea of creating the 6 inch fall into the pond was to allow for overlap of liner from stream to pond with out having to seam the liners with tape. If i go with an RPE liner how is the seaming process vs EPDM which one is better? It would to costly for a liner big enough to make it all one piece without wasting a lot of liner.

Combatwombat did you use any underlayment when installing your RPE liner? There is a pretty substantial cost saving with RPE over EPDM but the headaches of trying to find a miniscule leak in the liner might not be worth the savings.

 

[Taneli]

New design, excuse my kindergarten level art skills lol

 

[combatwombat]

Combatwombat did you use any underlayment when installing your RPE liner? There is a pretty substantial cost saving with RPE over EPDM but the headaches of trying to find a miniscule leak in the liner might not be worth the savings.

I did, but I used a woven underlayment similar to road fabric. I have sandy soil so I felt it was sufficient.

The proper way to seam RPE is to heat weld it. The pros make it look easy, but that has not been my experience. I even bought a proper heat gun and practiced with many scrap pieces but never got a seam I was very thrilled with.

I just completed a seam for a new stream with a couple tubes of Loctite Marine Adhesive sealant. Time will tell how durable it is. Sticky stuff!

 

[Taneli]

I did, but I used a woven underlayment similar to road fabric. I have sandy soil so I felt it was sufficient.

The proper way to seam RPE is to heat weld it. The pros make it look easy, but that has not been my experience. I even bought a proper heat gun and practiced with many scrap pieces but never got a seam I was very thrilled with.

I just completed a seam for a new stream with a couple tubes of Loctite Marine Adhesive sealant. Time will tell how durable it is. Sticky stuff!

So if i have to make a seam you would recommend EPDM?

Do you know if any companies can seam one for you from the factory in an L shape if you give them the measurements?

 

[combatwombat]

So if i have to make a seam you would recommend EPDM?

Not necessarily. You can also use a RPE specific seam tape.

o you know if any companies can seam one for you from the factory in an L shape if you give them the measurements?

Yes, absolutely. It’s called a box-welded liner.

 

[GBBUDD]

New design, excuse my kindergarten level art skills lol

I WOULD SWITCH YOUR INTAKE AND BOG. the bog will push water toward your intake the stream will empty at the intake. plus your second waterfall can be seen for the main patio as well as the fire pit i'd take the intake and follow the shape of the patio making it look like you built around nature not the other way around.

i have never done so but i have heard epdm seam tape can be used on hdrpe. one other trick is to seam your seam tape so you have multiple barrier before water gets past the overlap seam

Seaming EPDM liner

Seaming is not difficult but it does require some foresight and thought. Hopefully this list will help you to create a seam that will last for many, many years, issue free. If you can seam your liners in a driveway or somewhere flat that is by far your best option. The method below is how I...

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