Leak Detection


If you suspect your swimming pool is losing water, or you’re having to top it up excessively, it may well have sprung a leak somewhere in or around the pool shell, the underground pipework, in the equipment in the plant room, or a combination of locations. With a newer and a well serviced and maintained pool, leaks – particularly those in the pool structure – are typically not an issue.

If your pool is very old, the potential for a leak through the effects of wear, tear, ageing or neglect is increased. A leaky swimming pool is a potentially serious matter and can lead to other issues such as excessive water consumption, increased chemical and heating costs, ground settlement and backfill erosion, and catastrophic structural failure in the very worst cases, particularly if symptoms are ignored and not addressed.

Diagnosing leaks, finding them, and rectifying them quickly before further damage results is a highly skilled job requiring high levels of training, expertise, experience, and specialist equipment. It also requires a systematic approach in order to keep the speed and cost of both diagnosis and repair to the bare minimum, and ensure precious hours on site are not wasted. It is not a job to leave to amateurs, cowboys or fly-by-nights.

Here at Deep End Pools we have many decades combined experience in diagnosing, locating, and rectifying leaks in pools and pool equipment. Our highly trained technicians work rigorously to SPATA standards and employ the very latest techniques and technologies to the task at hand.

In our extensive experience we find that most leaks can be identified and remedied very easily. We work to a systematic 4-stage process, as detailed below, resulting in over 75% of pool leaks we are called out to being solved within 1 hour! So, if you suspect you have a leak, we strongly recommend you do not delay and get in touch with us today.

Deep End Pools’ 4-stage swimming pool leak detection programme systematically allows us to find and deal with your leak in the quickest and most straight forward way, as follows.


An initial visual investigation is always the first step in any leak detection process. This initial investigation involves a visual survey of the swimming pool plant room, shell, and the swimming pool’s surrounding areas.

A Deep End Pools engineer will visually inspect in and around all the equipment in the plant room and the pool’s shell for any obvious and immediately apparent signs of leakage. Our technician may also test run the equipment on different plumbing lines to help narrow down the possibilities. This first stage eliminates any common and more obvious faults such as a faulty multiport valve or a leaking pump or filter, or any failed seals, gaskets. or union connections.


If the initial visual inspection is inconclusive, the second stage is a pipework pressure test.

A swimming pool pipework pressure test involves each and every accessible plumbing line to and from the pool being capped and charged with pressurised water, according to SPATA standards. The pressure is normally maintained and monitored for 15 to 20 minutes, which allows our technicians to deduce if any of the pipe runs underground, behind the pool’s shell or under the plant room are losing pressure. If any pipelines are found to be losing pressure, that means they’re losing water. Each line is checked in turn and this test gives an immediate positive or negative result for each pipe run.

*NB: Should a diving team be required to carry out underwater tests in filled swimming pools, this service can also be provided. In the vast majority of cases, upper areas of the pool can be tested without the need to dive.


If stage 2 shows no conclusive leaks in the pipework or plant room, stage 3 is a sonar detection test. Sonar leak detection is one of the most technologically advanced swimming pool leak detection systems available. The specialist sonar equipment we use allows us to establish if water is tracking to earth and to actually ‘hear’ where the water is escaping from the pool.

On older pools there may be more than one area within the pool’s shell from which water is escaping, but the sonar equipment allows us to ‘listen’ for this. This specialist test has successfully diagnosed hairline cracks in the past that have not been visible from poolside and are easy to miss once inside the pool.


Using a specialist dye injection technique, we can trace water movement in failed items of equipment in the pool shell. Once a leak has been tracked down using the sonar equipment, it’s possible at this stage to ‘hear’ the leak, but using a specialist dye makes it possible to ‘see’ the leak.

Using the dye injection in the area identified as suspect allows us to see the flow of water escaping through a leak, and the direction in which it’s moving. Having then identified the exact point of water loss, this allows our experienced technicians to formulate the best mode of repair to stop it.

By completing the above tests systematically and diligently, any leaks are located and dealt with swiftly by a process of elimination, and rectified as professionally as you would expect from Deep End Pools.