How to recover from flooding?

[Kalico]

In the recent California storms, we ended up with our entire pool and most of the equipment under flood waters. All that was visible was the diving board.

The water that's in it now is brown. I can't see the bottom, but I can feel the mud and I can stir it up by brushing (at least in the shallow end). I kept it chlorinated at first, but we've had a LOT going on with flood recovery in other areas of life and the pool took lower priority. Now there is a lovely layer of green slime on the top. I have been scooping it off with the net, adding gallons and gallons of chlorine, and it's a little better. I might try testing the water soon, but the water is so brown I'm not sure how well I will be able to detect color!

So, the big question now is....what next?

I have not run the pool pump other than for a couple of minutes to see if it would run at all after being under all that water. It did. But if my (separate/standalone) hot tub motor is any indication ( ) it might not run for more than 10 minutes and then grind horribly and have to be replaced.

I am concerned about running the pump because I can't see if the drain is covered in sludge or debris. What if it sucks up mud and crud that clogs the pipes? And then I have to tear up the yard or concrete looking for a clog in the line?

I have an external pump that can be used to pump the pool water into the creek, and so I have considered doing a simultaneous drain-and-fill until the water is clear enough to see how bad the mud is at the bottom. Don't want to drain it, because the water level is pretty high in the whole area right now, not like our usual drought conditions. The normally-dry creek hasn't even fully drained yet, and it's been 4 weeks since the last storm. The bottom of the creek is not much deeper than the pool, so.....not taking any chances.

I MIGHT be able to stir up the mud while the external pump is working and get some of it to vacate into the creek while doing a drain and fill. Not sure if it would be enough to make a difference.

And of course, there's the vacuum....but that would mean running the pool pump. See above.

There was a time when a pillowcase got sucked into the skimmer and pulled all the way into the filter basket at the equipment side. I was terrified it would ruin something, but I was able to just pull it right out. So the pipes from the skimmer to the equipment are big enough to handle that....but not sure about from the drain to the equipment.

Wondering if maybe it's better to wait until spring and let the ground dry out really good, then drain it and see what's under there?

Sooooo....any advice or suggestions are most welcome at this point!

 

[AQUA~HOLICS]

Waiting till spring may stain the pool finish with the unknown material sitting on the floor.

 

[Texas Splash]

Believe me when I say you are not alone. Others have gone through the same or worse. It takes time. Before you can start a SLAM Process, you'll have to manually brush & scoop as much junk and muck out as possible. When you do start the system, consider running only skimmer suction for now. You will have to rinse the carts out more than normal, but eventually you'll get it. Once you feel confident you can run the system, start the SLAM Process. Be patient. Good luck!

 

[Bperry]

Wow, didn’t think San Martin could flood like that. We used to live in Morgan Hill and always wanted to move up to there.

Definitely don’t run the pump until you can see the drain. I think I might be in the camp of sweep any sludge from shallow end to deep end and then sump pump junk out from the bottom of the deep end 4-5” and then add clean water back. Then repeat.

 

[ajw22]

You need to vacuum the mud from the floor to waste before your pump and filter can handle clearing the water.

The best way is to have a pool company come in with a standalone vacuum rig that will clean out all the dirt that settles to the bottom of the pool. That only costs you money and water.

 

[Kalico]

Thanks everyone! Really appreciate all the input. @Texas Splash holy moly! Yes, you've been where we are. Thanks for the pic. Your egret looks as happy as my mallard couple. (But I think mine are more green and slimy....)

@AQUA~HOLICS Thanks for mentioning the staining. I had thought about that....then forgot.

@Bperry we were shocked too! But Corralitos Creek runs right through our property. It takes most of the runoff from the area. Normally, it's not a big deal....but this time was much different on so many levels!

I do have a pool company coming out today to evaluate the situation and see if they have the right equipment and the right price (@ajw22 lol "only money and water"....what a perfect description of the past few weeks of my life! )

Unfortunately, our system doesn't have an easy "vacuum to waste" option. I stick the vac hose in the skimmer and it pumps directly to the filter. I have to open up the spherical housing, remove the cartridges, and just let the water flow out.

There's also no way to run just the skimmers without the bottom drain. It all seems to be one system.

Our external pump arrangement is a gas powered above-ground unit. There's a debris cage on the hose end for the pool side. It's obviously meant to keep debris out, not let it come through! And then basically a firehose that runs to the creek for the exit water. It does reach all the way to the bottom, but there's really no good way I can think of to ensure that it's pulling up more mud than water, especially when we can't see the bottom!

Here's a picture taken after some of the water had receded. You can see the diving board on the right of the pic and the white hoses of the pool sweep, but all the coping is still underwater. The yellow arrow points to a red cooler that made a journey of about 150ft from the other side of the house and through a couple of fences to get where it is, so the water was up as high as that little knoll it's sitting on. Beyond the fence, you can see water and the creek line is just beyond that.

 

[JoyfulNoise]

You can’t salvage that water. Your simplest, but perhaps expensive, option is to wait until the surrounding water goes away then have the pool completely drained using a high horsepower (gas powered) trash pump while simultaneously power washing the shell (at low pressure). This has to be done safely though so as to not pop the pool out of the ground if the ground is still saturated with water. If the pool doesn’t have a hydrostatic valve, then a couple of 3” diameter holes will need to be core drilled into the shell to create the necessary relief openings. They can later be filled with hydraulic cement and the plaster patched.

See what the pool company can do for you. This is NOT a DIY job …

 

[Kalico]

Pool guy was here. He reacted like @Newdude LOL...and he's just looking at it after the water has gone down and he can actually see the pool. Pic from today is below for comparison.

He was sure the equipment was toast. Coulda knocked him over with a feather when he turned it on and it blew out some debris and small pebbles(!!!), then filled up with water just like it's supposed to. Of course it only ran for 10 seconds. I'm still not holding my breath that it will make it past the 10 minute mark. In the pic, you can see the high water mark on the pool house and the height of the equipment. The pump is smaller and was entirely submerged.


Anyway, he says $2300 to pump it and acid wash it. I was actually considering an acid wash before all this happened, because of the ongoing black algae problem that I've never been able to get under control since we bought the place in 2020.

And @JoyfulNoise ...yeah, I agree. Not a DIY thing. I'm curious what you think of pool guy's recommendation compared to yours, which is more detailed but similar. More on the pop problem below (Question #3).

I have a few questions now...

1. How well will an acid wash work to actually kill black algae once and for all? Pool guy didn't seem to think it would ever really go away especially because of the pebble finish. Suggestions? I want to do what I can while the water is out. (But see #3)

2. What can an acid wash do for calcium deposits in the pebble finish? There's a good bit at the water line...and perhaps the whole pool?? (Aside: Pool guy says that pebble finish is not supposed to go all the way up to the coping...should have tile at the water level. But hey, I didn't build the pool. ) I'm including a picture below of the first summer we were here, when I drained it and refilled it b/c CYA was so high that I couldn't kill the algae with chlorine. In the pics, you can see how splotchy the finish is and the color it is at the top, closest to the coping, above the water line (click the thumbnail for detail). I am pretty sure it was supposed to be dark and got lighter from deposits?

And then there's the black death all over the walls. It's much better now, but not gone. There are only so many hours in a day to work on it and I admit I got bored. And tired. And sore....



3. Ok, about all the concerns with the shell popping out due to water. Pool guy said he has never seen a gunnite pool pop like that. He's seen pools all over the valley here that even sit empty for years and years, and never have a problem. Fiberglass...whole different story. They are so light they pop right up. But gunnite, with the steel structure and the weight like concrete....he's never seen it happen. Then again, he's never seen flooding like we've had either. I have to think the ground is saturated, since the creek hasn't even fully drained yet.

There's a risk of staining if I wait, and a risk of pop damage if I don't. But the idea of drilling holes is new....so maybe that's the answer. Does that allow water from the surrounding ground to seep in, instead of pushing it up? And about staining...will that matter if we're acid washing anyway?

Here's how we look today. Isn't the green slime lovely? It coordinates with the grass weeds so nicely.
(The pump hose is still in the pool because at one time, we thought we should pump the pool while it was raining so it would not get too full. lolololol.......)

 

[JoyfulNoise]

Gunite pools can pop out of the ground just as easily as any other pool. If the ground around the pool is saturated with water then the buoyant force from all that water will easily lift a shell out. It’s not going to float to the top of the ground but all it takes is a couple of inches of float to completely wreck the plumbing and throw the entire pool off level. Maybe ask this guy how he felt about seeing his pool’s concrete shell from the outside in -

Sure, it’s Louisiana, but the buoyant force is a fact of physics, no geography, so it can happen anywhere. As long as you can dig around the pool and not find water, you’ll be ok. But if the ground is saturated, you risk the pool shell. And that’s an entirely different financial problem …

Acid washing is going to destroy your plaster. It’s almost never a good idea. I would skip that and just have them drain and wash down the pool.

Black algae is a major pain but acid washing doesn’t fix that. You could try to apply a strong algaecide to the plaster surface when it’s drained to try to kill it but the roots (hyphae is the correct term) from black algae can grow deep into the plaster. You’ll need to follow the black algae eradication process that TFP suggests and it’s going to require and lots of chlorine. You may never get rid of it entirely so you will have to wait until you’re ready to replaster the pool.

When you replaster, you can remodel it and get rid of the PebbleTec up to the coping. That’s a 20 year old aesthetic design choice that pool builders thought was a good idea but turned out to be a maintenance headache. No one does that anymore. So when you remodel you can add a proper water line tile and maybe even redo the coping and deck if you feel like spending lots of money.

 

[Kalico]

> As long as you can dig around the pool and not find water, you’ll be ok.

How far would one need to dig to find out? We don't have nearly the level of water sloshing about that this video shows, and I don't think we would literally "hit water" if we dug anywhere. But I'm concerned about whether the groundwater has gone down "low enough" - whatever that translates tof. The closest measure I have is the creek itself, which still has some water, maybe 6 - 8" deep. The pool is located about 60-70 feet from the creek. Is there any way to sort this out and be sure? If not, I'll wait until I'm sure the creek has dried up. Oh wait...it might stain if I wait too long....ugh!!

 

[Bperry]

> As long as you can dig around the pool and not find water, you’ll be ok.

How far would one need to dig to find out? We don't have nearly the level of water sloshing about that this video shows, and I don't think we would literally "hit water" if we dug anywhere. But I'm concerned about whether the groundwater has gone down "low enough" - whatever that translates tof. The closest measure I have is the creek itself, which still has some water, maybe 6 - 8" deep. The pool is located about 60-70 feet from the creek. Is there any way to sort this out and be sure? If not, I'll wait until I'm sure the creek has dried up. Oh wait...it might stain if I wait too long....ugh!!

Any amount of pumping junk out will help. Try pumping out 6” and then filling it back up with fresh water. Not sure when the cost/benefit analysis pushes you to the professional pool guy though.