Case Study: Hidden Burst Pipe in Trinity Beach

We were called to a job in Trinity Beach because the owner had noticed that the front of their property had become very boggy. When I arrived, it was obvious something wasn't right with the plumbing; there was a large puddle in front of the property. I checked the water meter and could see that it was running constantly.

This particular Trinity Beach home had a significant setback from the road, with an elevated section near the house. I spoke to the property owner, and they mentioned noticing one wet spot up the hill near the house that was also wet but they didn't think it was the leak's location, as it was about 20 meters away from the boggy area at the front. I investigated the wet area and quickly found the leak.

It was easy to find the leak on a job like this, as the pipe had been buried very shallow, and visible signs of a burst pipe were evident on the surface. If the pipe were buried deeper underground, we would have had to use our advanced leak detection equipment. We employ a few different options for leak detection:

Leak detection methods

For a job like this, we typically use a line transmitter and a locator. The line transmitter hooks onto the copper pipe at the meter, sending a frequency through the pipework. We then use a locator to trace the line, mapping its underground path. We mark out the pipe on the ground with spray paint so we can follow it and pinpoint the burst pipe.

Next, we use an acoustic leak detector, following the line we've marked on the ground. The acoustic leak detector picks up noise in the ground and displays the volume. As we move along the marked line from the line transmitter, we observe whether the value increases or decreases, moving along until we pinpoint the highest value, which indicates the leak's location.

Once we find the leak's location, we can excavate and repair the burst pipe.

One challenge that can arise with this method of leak detection is when the water service has been run in a plastic pipe. If the water pipe is plastic, we can’t connect the line transmitter as it works through electrical charge. If this is the case, we can still find the leak with the acoustic leak detector, but it's a little more difficult. This was the case for the job in Trinity Beach, but it wasn't an issue as we could find the leak very easily.

What can cause a burst pipe?

There are a few different contributing factors that can lead to an underground burst pipe. In this case, the water pipe had been buried with bricks and rocks on top. Over time, these harsh edges put pressure on the pipework and wore through it. This highlights why correct backfilling is so crucial during construction.

The water pressure at the property was also very high (900 kpa), which can be a contributing factor, especially for older pipes. The combination of these two elements led to the burst pipe and a significant water leak. The high pressure also meant that, even though the pipe leak was small, a large volume of water was lost.

How to Tell if You Have a Burst Pipe

There are a few ways to tell if you have a leak or a burst water pipe:

• A Much Larger Water Bill Than Expected: If your water bill is double or triple your usual, there’s a good chance of a leak. The downside is you might have had a leak for weeks or months before realizing. Small leaks might not show a big enough difference to immediately notice.

• A Section of Your Yard is Very Boggy: If your yard has a boggy section, even without recent rain, it’s a strong indication something isn't right, and you should investigate if a burst pipe is the source.

• Your Water Meter is Constantly Running: While most people don't check their meters for fun, if you suspect a leak, this is a clear sign.

How to Investigate a leak

The best way to check for a water leak is to monitor your water meter. If the meter is ticking over while no one is using water, you have a leak somewhere. Just ensure no water-consuming appliances (like the washing machine, dishwasher, or pool top-up) are active, as they can mimic a leak.

A large leak will show itself very quickly on the water meter so you should have no trouble identifying the issue. Smaller leaks can be a bit more tricky to figure out. If you turn off all water usage and the meter appears to be completely still you may have a small leak that is going to take time to turn the meter over. If this is the case the best thing to do is take a picture of the reading on the water meter and come back in 15 minutes.

If the reading has changed then you may have a slow leak somewhere. You can take note of how many liters the meter has moved over a certain amount of time and determine how severe the leak is. In the case of the job in Trinity Beach the meter turned over about 7 liters in a minute this added up to 10,080 liters per day. Part of the reason the leak was so bad was because of how high the water pressure is on the property.

Repairing a burst pipe

There are a few ways to repair a burst pipe depending on the reason for the damage.

• Welding - This works when there is a small pin hole and the rest of the pipe around the leak is in good condition.

• Replace a small section of pipework - If copper pipe has been crushed and there is a small section that has been damaged it is better to replace the damaged section rather than just repairing the hole in the pipe. Also in the case of plastic pipe you will have to replace a section as welding isn’t an option.

• Replace a water line - In some rare circumstances a larger section of pipe will need to be replaced. For example if the burst pipe is under a slab or a large tree or if there is extensive damage to a larger run of pipework.

  
  

Once we located and excavated the leak at the job in Trinity Beach it was a simple job to cut out a small section of damaged pipe and replace it. While I was on the job I did a free inspection for the home owner and found that the water pressure was very high. I recommended that they install a pressure limiting valve to preserve the life of the rest of their pipework.

The small section that I dug up was backfilled with rocks and bricks so there is a good chance that the rest of the line could be similar. They would be better off limiting the water pressure no then replacing the whole water feed if it continues to deteriorate.

If you've got a burst water pipe in Cairns and need our emergency plumbing services or you're looking for a local Cairns plumber who can help to investigate a potential water leak then give Oakland Plumbing a call on 0466 871 445.

We service the entire Cairns area and prioritise long-term solutions.