Pond Build

Paschendale52

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Hi all!

I'm finally working on a pond at our new house here in Albuquerque, NM. The excavation is done and I'm currently working on getting concrete footings poured for the walls. The pond will be basically a 20' x 10' square with dog ears in opposite corners. The walls will be ~2.5' tall and constructed from 2x lumber resting internally against rebar embedded in the footings on ~30" spacing. The horizontal boards will also be screwed into vertical 4x6s which will encase the rebar so that any forces would have to cantilever the 4x6 on its long edge and bend rebar. The footing and walls are about 12" below grade and the pond is excavated to ~3' beyond that, so a total height of 5' in the deep areas and 2.5' deep in the shallow areas. I'll probably have a ramp to a relatively large basking area so that there are areas that are in the neighborhood of 1' deep too. In the picture below I havn't yet backfilled and tamped the dirt in for the footing from where I over excavated (p.s. driving an excavator is a ton of fun....). As you may have guessed from the lumber construction rather than CMU, I'm going with EPDM liner rather than a concrete shell. I may revisit in a decade or so, we'll see. I also plan to have 2 windows which are ~5' x 2' mounted in aluminum Z-bar, one in the long edge and one in the dog ear which are on the far side of the picture (facing the house).

The current plan when I finish, hopefully in August or so, is to get some Bluegill and similar fish and move a couple of my turtles from indoors (180 gallon tank with 1 southern painted, 1 razorback musk, and 4 Mississippi maps) to the outdoor tank.

This brings me to my first big question. I'd like to have all native turtles in the pond, here in New Mexico which according to the all-knowing internet (definitely sarcasm) includes: Big Bend Slider, Midland Smooth Softshell, Eastern Spiny Softshell, Sonora Mud Turtle, Yellow Mud Turtle, Rio Grande Cooter, and the Western Painted.

The plan will be to get hatchlings and grow them out in the indoor aquarium for a couple years before transferring outside. I'm also strongly considering getting a couple adults immediately.

Does anyone have any recommendations for (a) which turtles specifically to aim for and (b) a reputable breeder from which to get said turtles?

I look forward hearing people's thoughts and I'll share more details as the build progresses!

Framing


P.S. If the mods think this is more suited to enclosures than water turtles, feel free to move it. I figured ponds and water turtle related things were more niche than enclosures in general so I'd put it where a more focused audience would see it.
 

Moozillion

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Hi all!

I'm finally working on a pond at our new house here in Albuquerque, NM. The excavation is done and I'm currently working on getting concrete footings poured for the walls. The pond will be basically a 20' x 10' square with dog ears in opposite corners. The walls will be ~2.5' tall and constructed from 2x lumber resting internally against rebar embedded in the footings on ~30" spacing. The horizontal boards will also be screwed into vertical 4x6s which will encase the rebar so that any forces would have to cantilever the 4x6 on its long edge and bend rebar. The footing and walls are about 12" below grade and the pond is excavated to ~3' beyond that, so a total height of 5' in the deep areas and 2.5' deep in the shallow areas. I'll probably have a ramp to a relatively large basking area so that there are areas that are in the neighborhood of 1' deep too. In the picture below I havn't yet backfilled and tamped the dirt in for the footing from where I over excavated (p.s. driving an excavator is a ton of fun....). As you may have guessed from the lumber construction rather than CMU, I'm going with EPDM liner rather than a concrete shell. I may revisit in a decade or so, we'll see. I also plan to have 2 windows which are ~5' x 2' mounted in aluminum Z-bar, one in the long edge and one in the dog ear which are on the far side of the picture (facing the house).

The current plan when I finish, hopefully in August or so, is to get some Bluegill and similar fish and move a couple of my turtles from indoors (180 gallon tank with 1 southern painted, 1 razorback musk, and 4 Mississippi maps) to the outdoor tank.

This brings me to my first big question. I'd like to have all native turtles in the pond, here in New Mexico which according to the all-knowing internet (definitely sarcasm) includes: Big Bend Slider, Midland Smooth Softshell, Eastern Spiny Softshell, Sonora Mud Turtle, Yellow Mud Turtle, Rio Grande Cooter, and the Western Painted.

The plan will be to get hatchlings and grow them out in the indoor aquarium for a couple years before transferring outside. I'm also strongly considering getting a couple adults immediately.

Does anyone have any recommendations for (a) which turtles specifically to aim for and (b) a reputable breeder from which to get said turtles?

I look forward hearing people's thoughts and I'll share more details as the build progresses!

View attachment 346074


P.S. If the mods think this is more suited to enclosures than water turtles, feel free to move it. I figured ponds and water turtle related things were more niche than enclosures in general so I'd put it where a more focused audience would see it.
WOWIE-ZOWIE!!!! This is gonna be SOOOOO COOOOOL!!!! :cool:
 

wellington

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Wow, very excited for you. Keep up with pics and postings. Love seeing pond builds. Can't wait to see it finished too
 

Paschendale52

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Rebar is in! 2 sets of horizontal rebar, wire tied in place at joints and such. Vertical rebar is in on 30" spacing most places and 25" spacing on the dog ear corners with 2 pieces at each corner. If you look closely you can see the 2 short rebar pieces are where the windows will be. 2 acrylic windows stretching from the two vertical rebars that are tall on either side of the short ones. I'm now ready for concrete, but we'll have to see what the timing for that is with travel and the rains and all.

Rebar1

From this angle you can see the 2 sets of horizontal rebar and vertical rebars. You can also see the "deep end" with the bottom drain covered up. It will get sunken in concrete during the pour. There are 2 bottom drains, one in the deep end, one in the shallow end which I'm planning on having a ramp up to the basking area which will be the far side. My hope is that with the shallow bottom drain being exactly below the transition from water to land, it will draw water and act as a bit of a skimmer since I don't currently have a skimmer installed. The nice thing about a lumber wall is that if I determine I need a skimmer later, I can cut it into the lumber wall and plumb it to the pump chamber later.

Rebar2
 

Paschendale52

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The concrete pour for the collar/bond beam went in today. I'll have pictures up in a week and a half or so when I get back from travel.

All in all it wasn't a complete disaster, but it didn't go well. The concrete mix was very dry and didn't flow as much as I thought it would. So being by myself and smoothing ~60' of footer wasn't possible. I have about 1/2 of footer with reasonably smooth (but not great) surfaces and about 1/2 of it with clear aggregate on top and basically not smoothed at all. From pour to too set for working or smoothing was around 45 minutes and I couldn't work fast enough. Luckily all of the footer will either by covered by the pond on the inside or gravel on the outside.

The other bummer about the footer is that because the concrete moved so little after pouring and flattening the best I could, there are several places where the horizontal reinforcements are aligning the bar that the concrete didn't flow under hardly at all. I removed a couple of the horizontal form reinforcement pieces and you can see the concrete didn't fill in much. The rebar in those areas still has some wiggle, which tells me that the hook in the rebar isn't fully encased in concrete.

I figure I'll have a better look at it in a couple weeks when I take the forms out. My current thought is to pour mortar or more concrete into the voids where the rebar is loose to try to strengthen it up. Does anyone have any advice for this sort of thing? @Markw84 perhaps.

I'm not super concerned about it because the walls are only 2.5' above grade so the pressure isn't so high and probably 24/28 of the rebar verticals are solid, but I'd like to fix it if I can.

For now I have the whole thing under a polyethylene tarp for the next 10 days or so.
 

Markw84

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Sorry, but just saw this post now for the first time with your tagging me. You are way too far along for me to offer much suggestions of value at this time.

I cannot visualize how you plan on anchoring the wall and stabilizing it. Looks like #4 rebar, and that is not much support just tied to a post on 30" centers. 30" of water against a straight wall is quite a bit of pressure. I only went 16" high and used cinderblock with #4 rebar on 16" center and every cell filled solid with concrete. The concrete could bond with the concrete footer and that creates the resistance to tipping with the rebar embedded in solid concrete all the way through the wall and through the footing.

I would definitely advise on putting in a skimmer. I would do 2 at opposite ends. A bottom drain even in 6" of water will do nothing to keep the debris off the top of the pond and the foam that forms as the filter goes through good times to a bit overload times. The most important is a skimmer at the end the prevailing winds will blow all surface debris to.

A bottom drain close to the farthest end from the waterfall/water return will encourage proper water circulation. The 4" piping is a great asset. I also used 3-4" lines as I used gravity feed into my filter chamber.

Loose rebar in a footing poured too dry is not good. No way to fix without breaking out enough concrete to re-pour concrete around the rebar. Concrete bonds well to concrete, but there must be enough room to get the voids to fill and tamp vigorously to fill / eliminate any voids once filled.

A window is a nightmare to place in a EPDM liner. It is easy to set into the frame and make that seal totally waterproof, but the issue is always the frame to the pond wall or liner. With a liner, you will need a large flange to pinch the liner into without absolutely any folds.
 

Paschendale52

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5 Year Member
Joined
Apr 23, 2015
Messages
138
Sorry, but just saw this post now for the first time with your tagging me. You are way too far along for me to offer much suggestions of value at this time.

I cannot visualize how you plan on anchoring the wall and stabilizing it. Looks like #4 rebar, and that is not much support just tied to a post on 30" centers. 30" of water against a straight wall is quite a bit of pressure. I only went 16" high and used cinderblock with #4 rebar on 16" center and every cell filled solid with concrete. The concrete could bond with the concrete footer and that creates the resistance to tipping with the rebar embedded in solid concrete all the way through the wall and through the footing.

I would definitely advise on putting in a skimmer. I would do 2 at opposite ends. A bottom drain even in 6" of water will do nothing to keep the debris off the top of the pond and the foam that forms as the filter goes through good times to a bit overload times. The most important is a skimmer at the end the prevailing winds will blow all surface debris to.

A bottom drain close to the farthest end from the waterfall/water return will encourage proper water circulation. The 4" piping is a great asset. I also used 3-4" lines as I used gravity feed into my filter chamber.

Loose rebar in a footing poured too dry is not good. No way to fix without breaking out enough concrete to re-pour concrete around the rebar. Concrete bonds well to concrete, but there must be enough room to get the voids to fill and tamp vigorously to fill / eliminate any voids once filled.

A window is a nightmare to place in a EPDM liner. It is easy to set into the frame and make that seal totally waterproof, but the issue is always the frame to the pond wall or liner. With a liner, you will need a large flange to pinch the liner into without absolutely any folds.
Thanks for the thoughts Mark!

I'll add in a skimmer. I was thinking the entire back wall would be basking area, but it will be easy enough to adjust that plan to account for one. It would be at the opposite end of the pond from the waterfall/bog filter return.

I think the plan for now will probably be to get a demo hammer and break out the bad concrete near the loose rebars, and any other I find when removing the mold, and then pour bag concrete mix to repour those section to get all the way around the rebar and ensure full encasement and strength.

I'm thinking now that I will add a 3/4" sheet of ground contact pressure treated CDX plywood all the way around the interior to bulk the final thickness of the walls to 2 1/4". My thought on the 30" centers is that pressure won't be that high for my depth, my plywood aquariums have always been rock solid with no flex using either 2 layers of 3/4" plywood or 3/4" plywood and 1/2" glass. The hydrostatic pressure at 3ft of water is only 1.3 psi. so the pressure trying to bend the bottom 2x6 is only ~220 lbs which evenly distributed across 2 1/4" of lumber is not much pressure at all.

I've worried some about the corner joints holding the thing together, which will be the stabilization against bending the rebar supports outward and tipping, but since the pressure is higher at the bottom than at the top the force will be trying to push the walls out where they're strongest, where the rebar enters the concrete footer. I'll still add wooden brackets to screw into with lag screws at the corners and possible steel brackets on the outside painted to match the lumber. But as long as I think about things in terms of my plywood aquariums from a pressure and force perspective at these depths I feel fairly comfortable. I'm open to further critique on the matter of course.

My plan for the window is below. I'll screw a 1" wide (each leg) piece of aluminum Z-channel to the 2x frame and then silicone in the glass to it on the front side. On the back the EPDM will go over the back of the glass and get sandwhiched by a flat bracket on the back side which is bolted to the z-extrusion. It should be just like the seal you see on liner-designed skimmers and waterfall boxes commercially available. If you have thoughts on this I'd love to hear them.

Pond window seal
 
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