Most pool plumbing is inherently flawed and restrictive

The pool plumbing is too often overlooked. The plumbing is the path that allows your pump to circulate water to and from the pool. Too many pools are plumbed incorrectly. This impedes the operations of the pool equipment.

When pools are plumbed incorrectly, there are a few reasons

For some pools, the schematics and spacing of fixtures is incorrect.

Other pools do not have enough fixtures. Many pools still have one main drain, when two are recommended. Some pools do not have enough skimmers. And some pools do not have enough returns.

Some pools may have enough fixtures, but they are plumbed incorrectly.

But the main problem with the way a lot of pools are plumbed is the size (diameter) of the pipes. The diameter of the pipes is too small. A major problem with this is that it increases the velocity of water movement through the pipes, which in unsafe…increased velocity of suction piping can increase the risk for entrapment and perhaps drowning from prolonged entrapment. Another problem with this is that it restricts circulation, hampers filtration, and hinders proper distribution of the chemicals…proper circulation and filtration – along with optimal water chemistry – are needed to maintain water clarity.

Some of these improperly-plumbed pools have adequate equipment, but others are also improperly equipped. The horsepower of the pump is too big. And the effective filtration area of the filter is too small. This becomes especially problematic…and unsafe.

The plumbing and the pump

FOR THE SAFE MOVEMENT OF WATER, THE PUMP AND PLUMBING SHOULD BE PROPERLY-SIZED SO THAT THE WATER MOVES…

  • LESS THAN 6-FEET PER SECOND (6 FPS) THROUGH ALL SUCTION PIPING, TO INCLUDE THE MAIN DRAIN(S) AND SKIMMER(S).
  • LESS THAN 10-FEET PER SECOND (10 FPS) THROUGH ALL PRESSURE PIPING, MAINLY THE RETURNS.

The smaller the diameter of the pipe, the faster the water moves through that pipe. This increased velocity through suction piping can increase the potential for entrapment and drowning. This is especially true if the pump (its horsepower) is too big.

The plumbing, pump and filter

When the plumbing, pump and filter are all correct and properly-sized to work together, a main result is the safe movement of water. Not only is safety prioritized, but the entire system performs better. And it works more efficiently, which saves you money each month.

The pump works as intended. And when the pump works as intended, so too does the filter to send filtered and clean water back to the pool.

  • For those of you also with a heater, filtered, clean, and heated water is distributed into the pool.
  • For those of you also with an automatic sanitizer, filtered, clean, and sanitized water is distributed into the pool.
  • And for those of you also with a heater and an automatic sanitizer, filtered, clean, heated and sanitized water is distributed into the pool.

Additionally, when the pump works as intended, all of the chemicals that you manually add to the pool are better distributed in the pool.

Pool Engineering

A good pool is a pool with correct plumbing schematics and proper pipe sizes.

A great pool is a pool with correct plumbing schematics and proper pipe sizes as well as properly-sized equipment, namely the pump and filter.

The best pool is a pool with correct plumbing schematics and proper pipe sizes as well as a variable speed pump and a properly-sized filter.


If you are removing and replacing your entire pool deck (regardless of what type of deck is being removed and how it is being replaced), this is absolutely the time to upgrade the plumbing schematics and pipe sizes. This would also be the time to upgrade to a variable speed pump and a properly-sized filter.


We hope this helps.

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We repair or replace plumbing.

If there is just one broken section of pipe, we can repair it. Or we can re-plumb this pipe.

Or we can re-plumb the entire pool. Additionally, we can correctly engineer your pool with proper plumbing schematics and pipe sizes as well as with properly-sized equipment.

Call us at 402-341-8132 or send us an email to info@expertpoolwork.com or submit a short form to discuss your pool and schedule free onsite consultation.