'Ridges' all over vinyl pool bottom

[araczynski]

I've inherited this above ground pool when we bought the house last january, so I've been working with it for 2 summers now. First summer was a learning experience, made much easier after discovering this forum (Thank you). This summer has been much much easier. Been using mostly regular chlorine/bleach from wallymart and occasionally those hockey puck sized chlorine tablets that I got last summer during the learning process. The pool chemistry seems 'good' to me based on the testing kit (forgot the name of it, but has all the normal tests (ph/alkalinity/calcium/chlorine/etc), blue box container with handle) anywho....

Seems since starting last summer and through this summer, the pool bottom (vinyl liner, 15x30 feet) has been developing these ridges all over. A small part of me thinks they might be roots of trees (pool is surrounded by them on 2 sides), but they're 'growing' too fast to be roots, plus the way some of the ridges intersect/end makes me think it can't be 'natural'.

In any case, i've attached some pictures of what I'm talking about. I'm not sure whether this is a chemical reaction to something, or if the sand bottom is moving around due to water pressure or what, anyone clue me in?

Since its getting to be closing time in my neck of the woods (omaha NE), i'm debating on whether I should drain completely and see what might be going on to try to fix. Not sure how often (if at all) the sand/bottom has to be 'reset'?

TIA

 

[kimkats]

If you press down on it with your foot what happens? Have you tried to use a rolling pin to smooth out?

Any idea how deep the sand is?

Worm? Moles? Roots?

Kim

 

[araczynski]

If you press down on it with your foot what happens? Have you tried to use a rolling pin to smooth out?

Any idea how deep the sand is?

Worm? Moles? Roots?

Kim

seems to be pretty hard, as if roots, haven't tried rolling it out, but only because judging by the hardness when pressing on it with my hand or foot it would take a seriously heavy roller to 'squish'. ridges might as well be cement, they don't budge.

its very compressed, even the tiny ones. i would think if it was moles/rodents, then the ridges would instead be little 'valleys', since the water pressure would make the earth/sand/etc fall down to take up the slack.

could be roots, but not sure why they'd be coming up so fast since i started with the pool last year, can they sense all that deliciously bleached water or something? plus if it was roots, i'd figure they'd rip through the vinyl by now, as high as the ridges are.

 

[kimkats]

Roots would be my guess as well with it being hard to the touch.

Can you shoot a pic of the area around the pool? Just how close are the trees? Could you trench around the pool to cut the roots of the trees?

I agree that if it were moles or such the tunnel would collapse.

It is up to you if you want to drain but I THINK (not sure) that you would have to get a new liner due to the old one drying out.

Keep us posted with what you fine out!

Maybe someone else will have some ideas.

Kim

 

[araczynski]

sorry didn't reply sooner, was a busy weekend/work day today. the pines (big/tall/old) are about 8 to 10 feet away from the pool. i'll try to shoot a pic tomorrow after work to give an idea. i don't have a problem replacing the liner, so not worried about it drying out or anything. i was thinking i'd have to reset the sand underneath anyway, but if its roots doing this then i'm not sure what I'd have to do, besides cutting them somewhere outside the pool and then digging all of the ones under the pool out.

would pouring a concrete bed be a solution (afterwards). then probably putting down more sand on top/etc. although with a 15x30 pool i'm guessing it'd have to be contracted to pour sounds like a big/$$$ project...

might just have to do some digging by the deck close to the pool to see what i hit. strangely though I do not see any root issues anywhere else by the areas around the pool. i mean i don't see roots coming out on the grass. not sure why they'd bother with the pool, unless there's enough moisture or something under the pool that the roots are migrating there for the water?

 

[kimkats]

You know what? It might be a good idea to just dig outside the pool where you THINK there might be a root coming to the pool. Just to see what you find.

Make sure you are far enough away from the pool to keep it from washing out.

Concrete under the pool-might be a good idea BUT roots can/will cause problems with that as well. Think about sidewalks with trees by them. I am seen my share of cracks caused by roots under them.

You can pour your own concrete. Just order a truck after you make the form. Watch Ytube to see how to float the top for a smooth finish. It will be $$ but it will all be material if you do it yourself. I don't know how good that will work with a pool though. I wonder if the foam boards under it will help with the liner on such a rough material as concrete?

Many questions, many ideas. MUCH thinking!

Good luck! Let us know what you find when you dig that hole/trench.

Kim

 

[cramar]

If you concrete you'll have to take everything apart, I think you could fix it without that level of expense.

I agree, they look like roots, if you remove the liner and move the sand base to the far side you should be able to remove them from the inside with a shovel and/or axe or bush saw (a good bush saw is cheap and would work well). You'll just have to be careful yanking out near the pool wall, then remove them a few feet back on the outside of the pool.
Then put the sand base back (a good time to add more sand if needed) and compact it, you may want to consider Gorilla Pad, its solely for preventing rips/tears to the liner.

I think you could repair this without alot of cost besides the liner, although it will be hard work.

 

[araczynski]

thanks for all the suggestions/info guys, i'll do some digging around this weekend or sooner and see what i run into.

 

[araczynski]

had some time this weekend to do a little digging, and i think its probably on the safer side to say that its probably roots. ran into a 3/4" root about a foot down in the dirt, pretty much inline with one of the ridges on the pool side.

now the problem is what to do about it...

how much time do i buy before the roots come back by taking the roots out?

could the roots be climbing because the trees aren't getting enough water? they're actually on a lower level than the pool.
either way, not a fun project, since the pool sits on the ground and is surrounded by a raised porch. at least the tree side of the pool gives me about 4 feet of headroom to work with...

 

[kimkats]

Oh man! That does NOT sound like fun at all!

Okay my thoughts-rent/borrow a trencher and trench as much as you can on the tree side. The idea is to cut the roots so they cannot do any more damage.

Now what can you put in the trench to keep roots from coming back? No idea here. Any one?

Kim

 

[araczynski]

i have read online that there are some tree root 'panels' that can be put in a trench, they're about 2 feet tall, but can't say i've ever seen them at a hardware store, but then again can't say i've ever had a reason to look for them before either.

a trencher does sound like a good idea, getting too old for a pickaxe with 4 foot clearance

i wonder how many years it would take for the stuff under the pool to decompose enough to settle after cutting the roots