Is a main pool drain necessary ?

[Ellen wilbur]

We had our pool remodeled due to cracks in the wall/leaking. A pool within a pool was constructed. All new filtration, skimmer, pumps, bubblers, heater/chiller. Pool equipment was removed from one side of the house and new equipment/plumbing installed on the opposite side.

We began filling the pool this weekend and immediately lost water. The main drain is leaking.
Found out - the main drain was not looked at, replaced. We do not understand how it passed a pressure test?

Today the contractor plugged the drain and has proceeded with start up.
Will this pass inspection? Should we accept the plugged drain or insist they correct the problem?
We were told correcting it would require the pool to be drained, opened up, repair drain, new cement and refinished.
Thank you for your time and advice... Ellen

 

[mknauss]

Main drain is unnecessary. Many pools operate just fine with inoperable main drains.

 

[JoyfulNoise]

Some municipal codes require a main drain. So builders will sometimes have no choice. But from a hydraulic standpoint, main drains are mostly useless. If the MD is run directly to a valve at the equipment pad, it can be somewhat useful but most are tied in series with a skimmer so they are very inefficient.

The history of the main drain in pools is quite fascinating though. Their original intent was as the name suggest - it was tied to a valve and it was the primary method of draining a swimming pool (gravity drain). Pool water chlorination is a relatively new aspect of pool care. Pools buoy before the days of easy access to sanitation chemicals were simply used until the water was too gross to swim in and then drained.

 

[i30swimmer]

My main drain hasn’t worked since I bought my house. My pool is clear, clean and works just fine running only the skimmer. Technically my drain is probably connected, but if I unplug the old 1960s Landon style skimmer system, main drain connection, I think I’ll open a can of worms. It’s just not worth it because the pool works just fine without the main drain. The only thing I notice is on very hot days, the deep end is cooler than the shallow end. That’s cured by doing a few laps or running the nautilus VC plus vacuum. Also if I ever have any real reason to need a drain, I hook up a vacuum hose and leave my manual at the bottom of the pool. Long story short: you don’t need a main drain.

 

[arvil]

Makes sense, if an above-ground pool doesn’t have one, why would an in-ground really need one? The only differences are shape, material, and location.

 

[markayash]

I wish somebody made flat Main drain covers. Don’t use it a lot and it has caused my robot to get stuck even when off.

 

[1poolman1]

I wish somebody made flat Main drain covers. Don’t use it a lot and it has caused my robot to get stuck even when off.

VGB made flat drains illegal.

 

[markayash]

VGB made flat drains illegal.

I mean to completely seal it off.

 

[1poolman1]

I've seen pool owners get a piece of 1/4" Lexan cut to the diameter of their cover and install it as a "dead" cover. Not sure what is available in Georgia, but we have a company, TAP Plastics, that will make them. Need someone to go to the bottom and remove the oldd cover and install the blank. So as not to cause pump issues, the main-drain plumbing was plugged as well at the skimmer.

 

[JoyfulNoise]

Nowadays there are ring drains you get where the top of the cover gets plastered the same as the pool and there’s a ring of suction opening. You still may need two drains spaced apart depending on the size to be VGBA compliant but the cover is basically the same height as the rest of the surface. These types of covers and channel drains have only been used in the last few years as those of us with older pools have to live with annoying drains that stick up off the surface.

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[pjt]

A main drain is like the intestinal appendix: it doesn't really do anything, has the potential to cause severe problems, and you can live just fine without it.

My pool was built without a main drain and I'm very happy with that decision.

 

[Dirk]

Your pool will not suffer at all without its main drain(s). In fact, it will be safer without it. They've come a long way to make the main drain safer, but no drain at all is the safest!

I had my main drains plastered over before I had my finish replaced. Love the improvements in safety, aesthetics and no more stuck cleaner or stubbed toes. If you can convince your builder to patch them up so that they are near invisible and water tight, that'd be the best all around solution to your dilemma.

 

[PoolStored]

Two skimmer, no main drain, 30K gallon pool. No issues, going on 3 years.

 

[BritDan]

Maybe it’s a minor advantage but I think my split/dual main drains can offer me piece of mind if I’m traveling for a week or so. i can adjust the valve to pull from the main drains only in times of turbulent or windy weather to be confident that the wind can drop the water level below the skimmer height and not risk the pump pulling in air. And I’m thinking that this autumn I can also adjust the valve the same way so the skimmers don’t get clogged with leaves too badly and starve the pump, again, if I’m traveling. we have a tonne of trees and vegetation around the pool. I don’t have an auto fill and the rest of my family are not team players when it comes to pool maintenance So it’s mostly me or no pool work gets done!

 

[duraleigh]

Two skimmers, no main drain, 43K gallon pool. No issues, going on 15 years.

 

[markayash]

Maybe it’s a minor advantage but I think my split/dual main drains can offer me piece of mind if I’m traveling for a week or so. i can adjust the valve to pull from the main drains only in times of turbulent or windy weather to be confident that the wind can drop the water level below the skimmer height and not risk the pump pulling in air. And I’m thinking that this autumn I can also adjust the valve the same way so the skimmers don’t get clogged with leaves too badly and starve the pump, again, if I’m traveling. we have a tonne of trees and vegetation around the pool. I don’t have an auto fill and the rest of my family are not team players when it comes to pool maintenance So it’s mostly me or no pool work gets done!

I have the same issue, especially in the fall.
I travel and am gone 2 and 3 weeks also.
Actually debating hiring a pool service to get leaf’s out and empty the skimmers but not sure they can resist adding chemicals

 

[Dirk]

Maybe it’s a minor advantage but I think my split/dual main drains can offer me piece of mind if I’m traveling for a week or so. i can adjust the valve to pull from the main drains only in times of turbulent or windy weather to be confident that the wind can drop the water level below the skimmer height and not risk the pump pulling in air. And I’m thinking that this autumn I can also adjust the valve the same way so the skimmers don’t get clogged with leaves too badly and starve the pump, again, if I’m traveling. we have a tonne of trees and vegetation around the pool. I don’t have an auto fill and the rest of my family are not team players when it comes to pool maintenance So it’s mostly me or no pool work gets done!

That is an important consideration to understand, Ellen. Without a main drain, if for some reason your water level drops below your skimmer opening, or the skimmer gets clogged, your pump can get starved and can possibly get damaged. But a main drain would solve for a low level only if you have the type of skimmer that shuts itself off when the water level drops. Otherwise, it won't matter. An open main drain would solve for the clogged-with-leaves scenario.

An auto-filler can help combat the potential low-level problem, as it would always keep your pool full. Well, theoretically. If the auto-filler fails (they can, and do) then that protection would go away. And, of course, Murphy's Law dictates the auto-filler will only fail while you're on vacation!! I have no drain and auto-fill and have never had a problem. The auto-filler failed once, but got stuck on, not off. I was home, noticed it, fixed it, and it hasn't happened since. I think it got stuck because I sent a bunch of crud down the filler supply line when I was working on that plumbing, so it was a fluke occurrence. Anywho, it's something to think about before you decide what to do.

As a secondary "safety," I have a webcam on my pool and can watch it while away. I can monitor water level and water color, watch for any algae event, and watch the squirrels drink the water! It's the next best thing to being there, and better than trusting a neighbor or service to keep an eye on things pool.

 

[Shirker]

I wish somebody made flat Main drain covers. Don’t use it a lot and it has caused my robot to get stuck even when off.

Agreed! Pools with a main drain are required to have two now (to prevent someone from getting suctioned to it). So a flat drain should be plenty safe, right?

 

[JamesW]

Some municipal codes require a main drain.

Maybe for a public pool, but I don't think that any local codes require a main drain on a residential swimming pool.

ANSI/PHTA/ICC-7 2020 American National Standard for Suction Entrapment Avoidance in Swimming Pools..

The purpose of this standard is to establish anti-entrapment performance requirements for public and residential swimming pools, wading pools, field-constructed spas and hot tubs, and any other bather-accessible body of water, including but not limited to, catch pools, infinity edge basins, and...

issuu.com

ANSI/PHTA/ICC-7 2020 American National Standard for Suction Entrapment Avoidance in Swimming Pools..

Published on Apr 19, 2021

The purpose of this standard is to establish anti-entrapment performance requirements for public and residential swimming pools, wading pools, field-constructed spas and hot tubs, and any other bather-accessible body of water, including but not limited to, catch pools, infinity edge basins, and water features that contain a skimmer, fully submerged Suction Outlet Fitting Assembly (SOFA) or vacuum port fitting. The term “pool” is used throughout this standard as an identifier for these bodies of water.

 

[Dirk]

I've noticed that when citing building codes related to pool drains, some builders and owners alike (even inspectors and planners) confuse the excerpts as meaning there must be a drain, when in reality they're only saying that IF there is a drain it must comply with various requirements. I think the way they're worded leads to confusion on this point.