Using downspouts to fill swimming pool?

JimMarshall

Gold Supporter
TFP Guide
Jun 5, 2017
755
Oil City PA
I have this idea (maybe a crazy idea) about trying to put an “auto fill” on my AGP, only using rain water instead of my well. My current iterations of this plan involve either:

(1) A pipe plumber off my downspout to provide water to the pool and A float switch that actuates either a 3 way valve -OR- 2 single valves to divert the water either through a sediment filter and into the pool, or down the drain based on the level of the pool.

OR

(2) A rain barrel/holding tank located under my deck for the downspout to flow into. This rain barrel will have a water level activated sump pump in it that discharges through a sediment filter and into the pool. A float switch that determines the water level in the pool will determine whether or not the pump has power. So, if the water level in the pool gets low enough to activate the switch, it will energize the sump pump, as long as there is water in the rain barrel it will get pumped out into the pool. If there is not water in the rain barrel, as soo. As it rains and beings to fill up, it will kick on and start emptying the rain barrel as it continues to fill, until the pool has enough water or the rain stops and the barrel doesn’t refill.


With either choice, I would install an overflow off the skimmer so that if something went wrong with the system, it wouldn’t allow the pool to be inundated with water.

My roof is a shingled roof.

Does anyone see any any problem with this? Will I be introducing any undesirable chemicals to m water this way?
 

#40Fan

Well-known member
Jul 12, 2018
173
SE, Colorado
I would go with #2, but not automated.

How big are rain barrels? How much does it rain there? Are you really going to be able to sustain the loss amount through rain fall?
 

ajw22

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TFP Guide
Jul 21, 2013
6,786
Northern NJ
We'd love to see pics of what you rig up.

Test the PH and TA and CH of the rain water. It will give you an idea of how it will affect your water chemistry.

You may need to pour some CL into any barrel/tank you use to accumulate rain water to keep algae from growing in it. Last thing you want is for algae to grow in the tank and dump it into your pool. It would take you a while to figure out why you are constantly fighting algae breakouts.
 

Leebo

Admin
TFP Expert
LifeTime Supporter
Jul 21, 2011
8,692
Eastern Ohio
We have two 250gallon tanks behind the pool we harvest water into each year. As mentioned above keep an eye on the FC level as algae will want to grow. Add some bleach and mix every now and then to help.
 

Dirk

Gold Supporter
TFP Guide
Nov 12, 2017
4,377
Central California
It's not a crazy idea. I wrote extensively about my own version of the same experiment, here:

Water softener connected to auto fill, and new plaster start up. - Page 7

I was on a quest to solve for CH rise (a problem where I live), so I tried replacing pool water with rain water. Worked great. I actually lowered my CH. I ended up abandoning the rain water project, though, and solved for CH another way, and here's why:

In order to determine what your new fill system will do chemically to the pool, you need to test the water coming off the roof, not just the rain water from the sky. It was a surprise when I did: the rain water was great (I post test results in my thread). But the rain water collected off the roof was laced with CH from the roof materials, which was not what I was after.

CH in your pool might not be as big a deal, but if your roof contributes to CH, it will build up in your pool over time. Then there was the issue of the birds. Pools are bird targets, but there is no perch for them (generally) so they have to do bomber runs. But they sit on roofs, so you are not only increasing their target area, you're making it significantly more comfortable for them as well! And then there is the general crud that comes off the roof: dirt, dust, and roof shingle particles, etc. The pretreating in the barrel with chlorine, and the filtering you're planning should address these issues well. I was just running water right from the gutter into the pool and it would have been a problem. Nothing my pool's chemistry and cleaner couldn't handle, but that didn't appease the icky factor that was stuck in my head!

Then there was the logistics. My system was all manual, so there was some wrangling involved, emptying pool water, setting up the drain, managing the fill, etc. My ultimate solution requires no effort.

Sounds like you've worked out all the bugs I would have had. One thing, which I learned here. If you're goal is to just fill then this might not matter. But if you're looking to replace pool water with rain water then you might consider how you introduce the rain water to the pool. Fresh water floats on salt water. All pools eventually become saltwater, even if you don't have an SWG pool. So if you introduce the rain water at the surface level, a lot of it will just meander over to your overflow (also at the surface) and dump right out. So either introduce the fresh water low in your pool, or have the main pump circulating the pool when you do (or both).

Good luck. Anything you do has got to be better than well water, right?
 

JimMarshall

Gold Supporter
TFP Guide
Jun 5, 2017
755
Oil City PA
I would go with #2, but not automated.

How big are rain barrels? How much does it rain there? Are you really going to be able to sustain the loss amount through rain fall?
If it’s not going to be automated, there’s no point in it for me. If I’m going to have to drag a hose out, monitor the level, etc, I might as well just monitor the level and hook the hose up to my outside spigot.

If doing #2 I would likely see myself using a 250 gallon palletized tote. We actually get a decent amount of rain here. Save for a boo boo I made draining water from my pool when it got too high for the skimmer to skim, I haven’t had to add water yet this year I don’t think. The rain has just been keeping up with it.

We'd love to see pics of what you rig up.

Test the PH and TA and CH of the rain water. It will give you an idea of how it will affect your water chemistry.

You may need to pour some CL into any barrel/tank you use to accumulate rain water to keep algae from growing in it. Last thing you want is for algae to grow in the tank and dump it into your pool. It would take you a while to figure out why you are constantly fighting algae breakouts.
I could see myself having a small stenner pump and recirculating pump or something to keep it squeaky clean. :eek:


It's not a crazy idea. I wrote extensively about my own version of the same experiment, here:

Water softener connected to auto fill, and new plaster start up. - Page 7

I was on a quest to solve for CH rise (a problem where I live), so I tried replacing pool water with rain water. Worked great. I actually lowered my CH. I ended up abandoning the rain water project, though, and solved for CH another way, and here's why:

In order to determine what your new fill system will do chemically to the pool, you need to test the water coming off the roof, not just the rain water from the sky. It was a surprise when I did: the rain water was great (I post test results in my thread). But the rain water collected off the roof was laced with CH from the roof materials, which was not what I was after.

CH in your pool might not be as big a deal, but if your roof contributes to CH, it will build up in your pool over time. Then there was the issue of the birds. Pools are bird targets, but there is no perch for them (generally) so they have to do bomber runs. But they sit on roofs, so you are not only increasing their target area, you're making it significantly more comfortable for them as well! And then there is the general crud that comes off the roof: dirt, dust, and roof shingle particles, etc. The pretreating in the barrel with chlorine, and the filtering you're planning should address these issues well. I was just running water right from the gutter into the pool and it would have been a problem. Nothing my pool's chemistry and cleaner couldn't handle, but that didn't appease the icky factor that was stuck in my head!

Then there was the logistics. My system was all manual, so there was some wrangling involved, emptying pool water, setting up the drain, managing the fill, etc. My ultimate solution requires no effort.

Sounds like you've worked out all the bugs I would have had. One thing, which I learned here. If you're goal is to just fill then this might not matter. But if you're looking to replace pool water with rain water then you might consider how you introduce the rain water to the pool. Fresh water floats on salt water. All pools eventually become saltwater, even if you don't have an SWG pool. So if you introduce the rain water at the surface level, a lot of it will just meander over to your overflow (also at the surface) and dump right out. So either introduce the fresh water low in your pool, or have the main pump circulating the pool when you do (or both).

Good luck. Anything you do has got to be better than well water, right?
CH is not a problem for me. I actually had to add it to my pool! My fill water has a VERY low CH - 50 or so. High pH andTA.

My goal here is twofold:

1) Always, or close to always maintain an “optimal “ (according to me) water level in the pool, with zero input from me.... the overflow would let excess rainwater that falls in the pool when it’s already full escape (maybe even I’d have a drain connected to another float switch and just go full blown autoleveler here) without me physically having to drain the pool, and the tank and associated pump system would add water whenever it was available from the sky.

And

2) Satisy my urge and desire to invent/tinker/play around with things and figure out the logistics of how to optimize such a system.


My original plan was a full line off the house hooked to an irrigation valve with the valve being activated by the float switch, but then I got to thinking about the rain water idea. Of course the algae, chlorine, etc does complicate things quite a bit. Perhaps I’d be better off with my original plan. - My well produces more than enough water and I don’t have any concerns with iron, etc because of it.
 

Dirk

Gold Supporter
TFP Guide
Nov 12, 2017
4,377
Central California
I could see myself having a small stenner pump and recirculating pump or something to keep it squeaky clean.
An aquarium pump might fit the bill. Just throw it into the water and plug it in. Like this one:

https://www.amazon.com/EcoPlus-Submersible-Aquarium-Fountain-Hydroponics/dp/B01FRUT9CC/ref=asc_df_B01FRUT9CC/?tag=hyprod-20&linkCode=df0&hvadid=167126276842&hvpos=1o1&hvnetw=g&hvrand=6021689649394626129&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9031745&hvtargid=pla-306784290911&th=1

They have them in every size and price point...

I'm with you on the automation. Its one of the reasons I abandoned the rain fill project. The alternative is automated, so it's the one I use.
 

Vickery

Gold Supporter
Silver Supporter
Feb 22, 2009
418
Perfection, NC
The common procedure is to divert the first 15 minutes (or so, depending upon the dirt load) of rainfall to the ground so that the dirt and other debris gets washed off, then send the rest to the reservoir. The old school method was to make the kids run out in the rain to do it. I have seen flap diverter arrangements that did that, but it was so long ago that I can't remember a source. Homesteading (preppers?) sources may help.
 

Dirk

Gold Supporter
TFP Guide
Nov 12, 2017
4,377
Central California
The common procedure is to divert the first 15 minutes (or so, depending upon the dirt load) of rainfall to the ground so that the dirt and other debris gets washed off, then send the rest to the reservoir. The old school method was to make the kids run out in the rain to do it. I have seen flap diverter arrangements that did that, but it was so long ago that I can't remember a source. Homesteading (preppers?) sources may help.
Much like how I was the family TV's remote control, back in the day. "Dirk! Turn it up a little!" or "Dirk! Channel 5!" Fortunately, we only had 10 channels!! ;)

That'll add to the OP's challenge, to divert the first 15 minutes worth, automatically. I figured I'd have to clean the gutters out once or twice a year, and solve for roof crud that way, but each time it rains makes better sense...