Do not worry.
As you know,I had to replace my skimmer due to a crack and it had bowed.
The new skimmer holes did not match the old and the weir plate and sikaflex silicone took care of it.
I will try to come up with some suggestions.
If you have EPDM, it will stretch quite a bit more than my liner!

Hi, I to had skimmer problems, we had to reset it due to a power outage and the water backflowed into the pump and it overflowed and dislogged the skimmer, when I came home it had almost completely overturned into the pond, I didn't figure it out until it happened again the next time we turned off the pump all the water from the pipe leading to the bio falls and all came rushing back down the hill and overflowed my skimmer. then it came clear what had happened, sorry for my rambling but.......we had to reset it..what a mess.......If when you built your pond you made sure to leave alot of slack in your liner under the skimmer, you should be ok. I don't know why they dont make a bar or something to hold the sides apart, as I have noticed ours bowing a little from the pressure of the soil around it....seems like they should have thought of this. Oh well, good luck with your job, btw, remember you have to lower the water level under the skimmer level to re set it.

goodluck..

Ouch, Mike. That moving groundwater could be a continuous problem in disturbed clay. Can you install some kind of frame to divert the groundwater until you have time and a plan to use concrete? Maybe a window well frame would work. Sandy

How about digging out around the sinking side and pouring in tiny pea gravel?
If you dig enough around the sunk in side to lift it just a little the pea gravel may settle under that side of the skimmer( Or you can force the pea gravel with a small shovel) and raise it enough to do the job until you can redo it. What would be even better is if you could get a friend to lift it a little while you force the pea grave in place.
It will be a little tricky as even with the 900 pro skimmer drained and the weir closed, the closed weir still leaks enough water so that you will have to keep draining it a little as you work.

Hey Mike as i told someone else in another post response " why dont you just throw in a couple of piranha" that should take care of it. LOL only kidding good luck!
BTW you were asking about my pond pics when i answered your recent pics thread i posted there and also have some in my recent post of "windy city plants"
again good luck glad i dont have those probs with my little pond (yet)
Mike R

Any way you can just drop the water level in the pond for repairs? You may be able to just jack it back into the correct position, shore it up with pieces of treated lumber and pour a a bunch of concrete under it without taking it loose from the liner.

I can drop the water no problem. Of course my reluctantly added fish now are an issue! On one side is the end of a row of stones containing a stream-lots of big ones. There also is the end of a concrete retaining wall I had to install to hold back the viscuous clay threatening to wipe out one fallstone. Behind and to the other side I am OK, I think, have to be careful of some plumbing.

I can't recall if the liner was fixed to the skimmer with some adhesive or not. Maybe silicon for some reason? Can't find instructions here or on-line, and I would have followed carefully. Any thoughts?

There is such suction with the wet clay that I will need to dig out all around to get it loose, I think. A fair sized job I only want to do once. This Pondsweep is 29" deep.

I wonder if I pour concrete under if it will sink also? I could put in a little drain, but that is a real job.

Also considering a stainless steet frame under the lip of the skimmer once it is level again if I can get in good footers. This is a steel town so I can find most anything.

Welcoming ideas, can see it coming together with all the good help. The liner glued to skimmer and do concrete pads sink are issues I hope can be addressed.

Thanks - Mike

If you followed the original instructions, there would be a bead of black silicone between the faceplate and liner. Then the faceplate had silver self drilling screws holding it to the skimmer box. It all can be reused except for new silicone. There is no glue.

I still have the original instruction booklet if you need to reinstall it. I

Thanks - all great info and ideas. I think I will lower the pond and inspect it all more carefully. Right now my thought is remove the skimmer out the front, depending on how the liner is arranged, and then work the skimmer pit by leveling and making plumb, do whatever concrete work and slide the skimmer back in.

Does this work? Easier than digging it out all around.

All of this seems to have happened abruptly, sinking, sides bulging in all around--I only hope I can wait til fall when fish are removed. Maybe dig some out now to relieve pressure?

I have two 5-7" fantail comets (is that a fish?). What size tub would be good for temporary quarters and for winter in the basement? Could I put them in an aquarium?

Two steps forward, one step back. My hobby.
Mike

Uh, Mike. You are supposed to leave the fish in the pond. They do just fine under the ice. Sandy

I think I have a handle on my skimmer problem but would like some advice. Much of the work here is mine but some was completed by another person--double trouble

{{gwi:223134}}

In digging around I discovered/remembered the skimmer was installed with lots of good gravel all around. This picture shows some of the problems.

The skimmer is surrounded by the end of a concrete retaining wall, heavy stone wall and two suction lines on the left, and a dock post in 18" of concrete, suction line, and overflow on the right.

The right front corner has sunk almost an inch. The material that was under the skimmer there has collapsed and made a big bulge or two in the liner. Disturbed material from digging out for skimmer and overflow is all that was behind the liner, nothing in front. Thus the slumping and developing bulges. Then the liner is locked in place by thick mortared stone.

In the fall, when the fish are in their winter home, I will empty the pond, unfasten the liner on the skimmer for the little slack I can have, and try to remove all the collapsed material from the bulges. I think I can level and shore the skimmer without a lot of digging (maybe) but I need help finding a way to stop the slumping, a way to get something rigid inside the liner at this location to hold back the material--treated planks, some other rigid bulkhead/sheathing. I see no reason to remove the skimmer and put in more gravel or concrete--what is there is working fine if it stays in place.

With a picture and description of conditions, along with the culprit process at work, any advice on approaching the problem, materials to use is most welcome. It seems pretty straight-forward; it is all the constraints that stymie me.

Thanks as always - Mike

Mike, I am no expert on anything but I am wondering if compacting the fill when you were installing the skimmer would have helped? Sandy

on anything, Sandy? Not in the opinion of anyone around here. That's all.

The contractor I hired/fired presented me with a lined pond, coping shelves of free and mortared stones, overflow installed, and a muddy, gooey unexcavated slot for the skimmer to go in. This soil was native and a bit like jello to tamp.

We compacted as much as possible, no machinery, all efforts constantly pushing mud down inside the liner to be removed by reaching in. The skimmer installation instructions said not to compact near the skimmer except lightly by hand--bulging and all that good stuff. So I followed the instructions and now the lightly compacted material is slumped behind the liner.

Your idea is something I should have thought more about back then, found a way to create stability, what I guess I need to do now hindsight being perfect vision.

Mike

Here is the non-expert again(lol)suggesting something that would normally make me cringe. Usually when someone tells me they did this I get the collywobbles. How about putting in a layer of clay and then (get this, my MG membership just may be revoked with this one)pounding in a layer of sand, then clay and then sand again.
I usually say this is a process to be avoided since it turns garden soil into building materials but in this case brick may be just what you need. ;) Sandy

Mike,

I feel for you, We have had similar problems as the posts I read of yours, The dirt is like gooey jello muck. I believe we had our trouble because it had rained quite a bit while we were building, digging our pond, I had some slumping around the pond edge that we had to scoop back up and it has been quite more of a challenge than my last pond build. I believe part of the problem lies with mine in the drainage around the pond area. It's bad, and we have already planned to run a length of corrgated drain pipe in a gravel base around the pond edges to try to keep the ground water around the pond at a minimum. The home we purchased had some french drains installed around the permitter and our back yard is on a slope, the pond is fairly close to the house. The pond filled up with rain water while in the digging process, 3 ft or so and it never did go down on it's own, at all....we had to pump it out, twice, It has been a real LARGE and sometimes painful project, my husband isn't a pond nut, so it's been a long summer...and has led to some squabbles between us. He has now kinda burnt out on helping me so I am finsihing it at a real snails pace. We still have much to do and don't know if it will get done this year. So don't feel bad, your not alone. We all share in your pain!
but we love our ponds....

I have a PS Pro900 also. The skimmer must be supported by the bottom - excessive side compaction will result in a smashed/deformed or broken box.
Besides the lousy clay foundation, you also have differential settlement due to proximity and liner attachment to adjacent concrete wall.

As for a fix - no amount of "shoring" will permanetly solve, it will eventually tilt. The ideal fix would be to totally remove and excavate for a concrete foundation using some thick plywood to support and protect your liner. If the foundation is constructed on clay it is a "floating foundation" and must steel reinforced and sized accordinly - I'd guessimate minimum 2' square 6"-8" thick.

Another option would be to compensate for the differential settlement. Can you use the existing wall to support whole box using some type of frame for support? Or build a similar concrete wall, or other support, on the other side. The box may still float but will remain level and functional.

Good luck.

hi sandyut--thanks for the advice and insight. I have a question if you are still reading this. You mention the differential settling caused in part by the concrete wall that is adjacent and attached by liner. Are you saying that ground water flowing behind the wall is channeled against the skimmer and the material can't settle on this side due to tight liner and lack of space beteen skimmer and wall? Or is it more than this?

I started with the idea of a concrete box but got tired just thinking about it. I'm now thinking to remove the skimmer at fall draw-down, put in plenty of gravel on the bottom and backdirt, connected to a 4" perforated drain pipe perpendicular to the concrete wall, intercepting water from uphill and draining skimmer area gravel with the idea of water taking the route of least resistance.

A lot of coulda-woulda-shoulda at this pond

Hi kittcatt - sympathy and shared experience is welcome to me. I just took some soil cores around the exposed perimeter of the pond and found conditions good, my under pond drainage working. Initially I had water at the surface, pre-pond, and that is gone. But I do think I need more, shallower drainage at the base of the hill near my skimmer.

Like you, part of our yard has lots of old drainage structure in it, uncovered with pond digging. Sounds like you are on the right track with new, additional drainage. Good luck--water is a formidable foe. Be sure to keep diverting water away from your house!

Of all the things I don't want to do again, digging is at the top of the list! Oh well, its a "hobby."
Mike

Mike,
I am glad to see your still in good humor, my husband has had his moments as well as I. Since it has stopped raining for several weeks, as of now were kinda dry here, things are much better, I would like to get more finished while it's dryer but time is short, we have so many things that take us away from this project, and then sometimes we just don't feel like digging ect. Were tired after work. So we just try to do what we can...last nite we went to my dads and got more rocks. I think if we don't get interupted tonite we may lay a few around.
Kitt