Mains water leaks can be a major problem, wasting litres of water down the street. We recently experienced this first hand when a mains pipe became damaged and created deep puddles all the way down the street.
While water everywhere may seem helpful for leak detection as the issue is obvious, as opposed to a hidden or concealed leak underground or within structures, locating a leak in this amount of water presents its own challenges.
This article will explore what mains leaks are, the risks they bring, the common signs, and how we tackled this recent wet adventure.
What Is a Mains Leak
Main water lines are responsible for delivering pressurised water from public utilities or main street infrastructure to properties, such as businesses or homes. These lines are designed to deliver consistent high-pressure water supply to properties, so when a leak occurs, the scale and wastage can be significant.
When a main line leaks or bursts it can cause localised flooding, as seen in our video, pressure loss across the network, extensive water damage depending on where the water flows, and contamination and safety concerns if the pressurised mains run adjacent to drainage or sewer infrastructure.
It is essential to address mains leaks as quickly as possible to minimise water waste, damage, disruption and health and safety issues.
The Challenge of Detecting Leaks in Saturated Ground
One of the biggest challenges associated with detecting mains leaks is how fast and far the water travels. As mains lines are pressurised, when a leak occurs it can expel litres of water in seconds, quickly saturating the surrounding ground. Water also naturally travels, but when propelled by pressure it can travel even further. This can significantly expand the search area when looking for the original source of the leak. It can also cause widespread damage and public safety concerns.
Methods for Detecting Mains Leaks
With mains leaks, the area where the biggest puddles are isn’t always where the leak started. The origin point is often metres back down the street. This means that our teams need to assess the entire area with specialised equipment and techniques such as:
- Pressure testing and flow isolation to confirm active fault zones
- Acoustic detection to listen for the specific frequency of mains-pressure water escaping underground
- Tracer gas where acoustic signals are masked by ground saturation
- GPR scanning to map subsurface infrastructure and voids beneath the surface
What Mains Leaks Cost When They Go Undetected
Mains leaks can cause extensive issues quickly:
- Water loss at mains pressure: even a moderate mains leak can lose thousands of litres in a single day
- Financial cost: water leaks can be costly with increased water charges, emergency repairs, and potential liability for downstream damage
- Structural cost: sitting water and sustained saturation can damage building footings, pavements, retaining structures, and surrounding infrastructure over time
- The contamination risk: where mains and sewer infrastructure run in close proximity, a sustained mains leak can create hazardous cross-contamination
- Environmental cost: water loss at mains scale is a significant waste of a precious resource
Mains water leaks don’t stabilise or stop on their own. If not addressed, they will continue to expel water at speed, compounding wastage, costs, and damages.
Signs of a Mains Leak
Bad mains leaks, like the one in the video, can be extremely obvious, but others can be more subtle. Aside from obvious puddling, water mains leaks can also present as:
- Unexplained wet or boggy ground that doesn’t dry out after rain
- Sinkholes, depressions, or sudden changes in ground level
- Unusual patches of lush, fast-growing vegetation
- Loss of water pressure across the property or network
- Water metre movement with all fixtures turned off
- Unexplained increases in water charges without corresponding usage change
- The sound of running water underground
- Discolouration or sediment in the water supply
If you notice any of these signs, it’s important to contact a leak detection specialist immediately for an inspection and tailored advice.
Why Mains Leak Detection Requires a Specialist
Mains leaks go well beyond standard plumbing investigations. Mains lines are often buried, pressurised, and run through ground that provides little to no easy surface access to the fault point. These factors combined with the sheer volumes of water loss involved and the distances that it can travel mean that detecting the initial cause can be difficult without the right tools and knowledge.
Professional water leak detection teams use specialised techniques and equipment to confirm the exact location of the fault. We trace the water and main line to scan or listen for the signs of escaping water underground. This then allows us to mark and excavate just the exact area where the leak is occurring for targeted repairs.
Tackling Extensive Mains Leaks Effectively
Mains lines are responsible for supplying water to the whole network, and when they spring a leak the consequences can be extensive and costly. Locating the source can also be tricky when water is flooding the entire area.
At LeakTech, our experienced technicians recently helped pinpoint the source of a major water mains leak that was flooding local streets, using specialised skills and equipment. If you’re dealing with unexplained wet ground, pressure loss, a meter that won’t sit still, or a suspected mains leak of any scale, give LeakTech a call for professional leak detection.
