Split main drains on the wall instead of bottom

SoCalSwimmer

New member
Oct 8, 2019
4
Southern California
Hey everyone,

First time poster, long time reader. I'm having my 50 year old 20k gallon inground pool remodeled (new skimmer, drains, returns, adding hot tub, new deck, etc). Thing is, my contractor wants to put a split main drain on the wall, not the deep end bottom. He's got it punched out about 16" below the proposed water line, just under the skimmer (see pic). He said the cleaner would take care of the bottom. It just looks weird to me seeing the main drains just below the skimmer. I do trust the guy and he seems pretty knowledgeable, just doing some due diligence.

Is this legitimate? I've read on the forums that some people consider main drains on the bottom to be obsolete. Thoughts?

MainDrains.JPG
 

kimkats

Mod Squad
LifeTime Supporter
Jul 10, 2012
45,832
Tallahassee, FL
I say NOPE! The main reason for the main drain is to mix the cool and warmer water in my eyes. That will not happen with them up there. Also them being there can be a problem if someone does a flip turn on the wall there. Their feet can kick/push off of them.

Are the current lines to the old main drain still good? Is he trying to be lazy and save some labor by not having to dig up and replace the old lines?

I say no main drain or where they belong on the bottom.
 

SoCalSwimmer

New member
Oct 8, 2019
4
Southern California
I say NOPE! The main reason for the main drain is to mix the cool and warmer water in my eyes. That will not happen with them up there. Also them being there can be a problem if someone does a flip turn on the wall there. Their feet can kick/push off of them.

Are the current lines to the old main drain still good? Is he trying to be lazy and save some labor by not having to dig up and replace the old lines?

I say no main drain or where they belong on the bottom.
I'm not worried about a flip turn, as they're on the narrow wall side if that makes sense. You'd be swimming toward the width instead of length. Anyway, the old main line is original and clogged up. The old main never really worked since we moved in years ago.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
31,162
Laughlin, NV
Only reason to install those is to protect your pump in case you let the water fall below the skimmer or the skimmer is clogged. Are they going to be hard plumbed (home run) back to the equipment pad or into the skimmer?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
18,959
Northern NJ
I don’t see why you want more drains that high up on a wall near a skimmer. It will serve no functional purpose.
 

SoCalSwimmer

New member
Oct 8, 2019
4
Southern California
Only reason to install those is to protect your pump in case you let the water fall below the skimmer or the skimmer is clogged. Are they going to be hard plumbed (home run) back to the equipment pad or into the skimmer?
I'm not sure actually. Is Home run better than attach to skimmer? I do get a decent amount of debris so I assume they would protect the pump if skimmer is clogged. He said he is going to install a dedicated vacuum port for a pool sweep that will act as the bottom cleaner/circulator.
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
31,162
Laughlin, NV
As far as a cleaner, get a robot. Do you really want to run your pump at a high rate, with your electric cost, versus a dedicated robot to clean the pool that does not use your pool pump? Let them put in the plumbing if you wish, but get a robot.

If you are unsure what you would use the side wall returns for, delete them.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
18,959
Northern NJ
He said he is going to install a dedicated vacuum port for a pool sweep that will act as the bottom cleaner/circulator.
My opinion is a vacuum sweep is the worst type of cleaner you can install. But the cheapest for a builder which is why you see them.

Use a robot or put in a pressure cleaning system that captures the dirt in its own bag.
 
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bmoreswim

Mod Squad
Gold Supporter
Platinum Supporter
LifeTime Supporter
Jul 16, 2012
6,298
Central MD
My opinion on why main drains are on the bottom are:
1) Historically there was a risk of entrapment from the suction (before VGBA). So they put them on the bottom so people would be less likely to get attached.
2) Dirt settles on the bottom and since old style suction and pressure cleaners aren't really that good, the main drain would also take in some debris. Though by their new design (VGBA and raised) they aren't very good at that except for the channel drains - great design.
3) Provides a point of suction far from the skimmers to circulate water better. Old pools didn't have as many heaters as today. We buy a lot more appliances these days.
4) Easy way to drain the pool if you just close off the skimmer valve (though many were also plumbed to the skimmer defeating this benefit).

And now that yours are on the side:
1) Because of VGBA drains entrapment is not an issue.
2) Robots are so good you won't even notice the difference vs. if the main drain had been working.
3) Have the PB install a deep return to help circulate down low if desired.
4) You do lose this functionality. But you can easily use a submersible pump if needed.
 

YippeeSkippy

Mod Squad
LifeTime Supporter
Jan 17, 2012
13,856
Evans, Georgia
I have the 2 wall drains nearer the floor. I like them very much as they're plumbed independently of the skimmer and I can open/shut my skimmer or the wall drains depending on what I want to accomplish. If for some reason my water dropped below my skimmer my pump would not suck air as the wall drains are feeding it also.
Conversely back in the dinosaur days of manual vacuuming we could close the floor drains a bit and the pump's suction would increase the pull on the skimmer, making it work better.

Maddie :flower: