How Do Plumbers Find Leaks Underground?

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How Do Plumbers Find Leaks Underground?

How Plumbers Find Leaks Underground

Have you ever wondered how plumbers locate leaks underground? Traditionally, one would have to perform destructive methods of leak detection by digging up the ground or by other methods that are prone to creating structural damages. 

However, nowadays, there are safer and environmentally-friendly ways that plumbers can find underground leaks. The water leak detection methods used now can be considered more technical, but they help prevent unnecessary damages and harm from occurring. 

If you want to learn more about how plumbers can locate underground leaks, then please keep on reading as we explore this topic in more detail below. 

Locating Underground Leaks With Leak Locators

Professionally locating underground water leaks requires a lot of technical skill and equipment. Most leak detection equipment functions by attempting to amplify the noise of the water leak so that the plumber can pinpoint its location.

To locate underground leaks, plumbers make use of what is known as a leak locator. Leak locators have specially designed sensors that listen for gurgling or hammering sounds of a cracked underground pipe. 

Leak locators have different types of sensors depending on the surface. A ground sensor, for example, is used to locate sounds through hard surfaces such as concrete, tiles, and asphalt. Meanwhile, a probe sensor picks up leaks through soft surfaces such as carpet or grass. 

Probe sensors may even be used as a contact probe for above-ground pipes or hydrants. Nonetheless, both ground sensors and probe sensors should be shock-resistant in order to reduce any other unwanted noise.

Leak locators are also equipped with a safety switch. The safety switch mutes sound to help protect you from sudden loud noises and sounds. The important takeaway is that leak locators are designed to not only detect noises caused by underground leaks but to mute out any unnecessary or unwanted sounds.

What Best Way To Find Water Leak Underground

Causes Of Leak Sounds

You might be surprised to learn that underground leaks make noise. However, what actually causes leaks to make a sound? There are actually three primary ways by which leak sounds can be created. 

The easiest and loudest sound to detect is pipe vibration. This is caused when water is forced through a crack in the pipe. The noise typically sounds like a hissing or a whooshing sound, which is why it is quite easy to recognise. 

Another cause of an underground leak sound is when water that is forced through the crack hits the surrounding soil. In this scenario, the type of material around the pipe affects the sound. For example, if the material is rock or gravel, you may hear a hammering or a knocking sound. On the other hand, if loose soil surrounds the pipe, picking up the sound might be more challenging. 

Lastly, another cause for underground leak sounds can be if water flows through the soil cavity. You might recognise this when you hear a gurgling sound as if you were listening to a brook or small stream. 

As previously mentioned, leak noises within loose or sandy soil along with swampy or saturated areas might be a little harder to find. 

However, as a general rule of thumb, the loudness and frequency of the leak noise can be impacted by the water pressure, pipe material, soil density and type of the surface (concrete, tile, etc.), and the depth of the pipe. The higher the pressure is, the louder the leak sounds will be. 

How Plumbers Find Leaks Underground

Non-Invasive Water Leak Detection

Non-invasive water leak detection is a method used by plumbers to examine underground pipes. This method is also one way that plumbers can find underground leaks.

Compared to conventional methods of examining underground pipes, non-invasive detection methods make use of smart technology such as thermal imaging. 

As such, leak locators that detect the sounds of leaks are not the only option for plumbers to find underground leaks. There are various forms of smart technology plumbers can use depending on the conditions of the pipe or the situation. 

Other examples of non-invasive water leak detection include acoustic leak detection, which makes use of ultrasensitive microphones for leak sounds; thermal imaging, which can monitor surface temperatures; and leak correlators, which use an electronic pulse to locate underground leaks.


There are various ways by which plumbers can find underground leaks. They can use leak locators, which functions by detecting the sound of the leak and blocking out any other unnecessary noise. 

However, plumbers are not just restricted to acoustic leak locators. They can also use other forms of non-invasive detection methods to find underground leaks.

When it comes to water leak detection services you need to take action right away. The good news is, Water Leak Detection Melbourne caters to emergency cases so you can call us anytime the need arises.

Keep your plumbing lines in good shape. Find those leaks as early as possible and save yourself time and money in the process.

Please call us for a free consultation today on 1300 425 325 or leave an inquiry on our website.