Hydrostatic Test Conclusions

If the water loss is the same whether the plumbing system is running or not, you will likely find the leak to be in the structure of the pool itself, and likely not in the plumbing system. This is not to say that you would simply discount the plumbing, as swimming pools can often be elusive in terms of diagnosing unexplained water loss. This is to say that you will begin your search by focusing more on the structure of the pool.

ripped pool liner

While you can effectively contain the return lines and skimmer lines in a pool the main drain at the bottom of the deep end can cause some difficulties in terms of isolating it but also in terms of evaluating the hydrostatic leak test results.

Main Drain Leak Detection

As covered in greater detail later in this guide finding leaks in a main drain of a swimming pool is more often a function of a process of elimination that results in the main drain being the only possible culprit. There is not one "standard" way to plumb a swimming pool so it is possible that you are not able to isolate your pool plumbing lines from the structure of the pool. If this is the case then further and more involved testing of the pool would be required.

If the main drain line is run back to your pump room independently from the skimmer line then you may not be able to isolate the main drain at all without swimming down and plugging it manually which is not an option for most pool owners. it takes a surprising amount of skill to dive to the bottom of a pool a work with tools effectively.

The fact that many pool owners will not be able to isolate the plumbing system completely can lead you to believe there is a structural leak when in fact the main drain line, or even the equalizer line running from the main drain to the skimmer, could be leaking. This is why multiple tests are usually required in order to determine with certainty where the leak is.

Rate Of Water Loss

Should your test results indicate a difference in rate of water loss when the plumbing system is running and when it is shut off, this can be a strong indicator for a problem existing in your plumbing system. You can not discount the possibility of a structural pool leak, but provides you with an initial direction to begin your water loss troubleshooting.

If you have a pool leak problem that prevents you from conducting this experiment due to drastic water loss conditions, you can monitor water loss for longer or shorter periods of time to accommodate the leak rate of your pool. Also note that weather conditions can skew the validity of your test findings so be sure to repeat the process if the results are in question.

Having the first test completed, you now have some hard evidence which will help you to narrow in on the water loss problem. A pool professional will begin to formulate a diagnosis of your pool with this information, not a clinical diagnosis, so much as a general intuition based upon recurring problems which are documented time and again in the industry.

Choose your water condition from the menu on the right. Each condition is defined if you hover over the condition tab.

The menu on the right is a chronological step by step process to determine where a swimming pool is leaking. This website is written as a readthrough technical assistance guide for locating leaks. When you believe you have identified where the pool is leaking you need to go to our sister website to see pictures and learn more about the actual swimming pool leak repair process.