Posted on 19 June 2019

What to do if there is a water main break


Burst water mains can be a lengthy problem to fix.

Burst water mains are annoying and time consuming to repair and the earlier they can be detected the better. A range of companies are involved in the repair of a burst water main, including vacuum excavation companies like Vac U Digga. We are often called out to clear the soil and water away from a water main pipe so repair workers are able to find the problem.

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What to do if there is a water main break

Water main line leaks can range in severity from a puddle to a flooded road so it’s important to take action as soon as you notice water where there shouldn’t be. Burst water mains can be caused by number issues, but old pipes and shifting earth are two main causes. As earthquakes are a regular occurrence in New Zealand water main leaks are also common. 

Main water line leaks also have major knock on effects to the surrounding area. A burst water main can stop water from reaching homes and also contaminate the water with the debris from around the leak. As these are both major disruptions to the lives of the neighbouring homes and businesses there is a number of authorities that need to be involved in the repair of the water main.

Four steps to take after a burst water main

There are four main things you need to do once you have found a burst water main or a water main leak. While water mains are one of the less dangerous utilities when they break, there is still major potential for damage to property, roads and footpaths, as well as the chance of water contamination. Do these four things before anything else to ensure that the leaking pipe is dealt with as soon as possible.

1. Call the Police and the Water Department

At the first sign of a leaking water main call the police as they will be able to shut off the road or location and evacuate the area. If you know, or can find out, the local water department you can call them and alert them to the burst water main. They will have emergency procedures in place for these situations. The police will also alert the local water department to the leaking water main if you cannot.

2. Limit your water use

If you live or work in the immediate area surrounding the burst water main you will need to limit your water use. Firstly because you can potentially run out of water if the burst water main is affecting your supply of water. But also any water pipe that is connected to the main water supply could possibly be contaminated. It is highly recommended that once you are alerted to a burst water main affecting your water supply you don’t drink any water from the tap to mitigate any potential illnesses.


Fixing burst water mains can take longer than expected.

3. Check for damage to your property

Depending on the severity of the water main break you may have had water inundate your home or business. Once you have the all clear to return to your home or business ensure that you inspect it for any water damage and take photographic evidence for insurance. Another big issue with burst water mains is their potential to shift the soil around the break. When you are doing your inspection also look for any potential foundation shifting or cracks.

4. Flush your pipes

After you’ve inspected your home or business for damage from the burst water main you will need to run all the pipes to clear any of the contaminated water. Start by running your cold water taps until the water goes clear and then for at least another two minutes after that. Next, if you have a hot water tank you will need to flush it out. Do this by running your hot water taps until the water runs cold, wait an hour then repeat.

Once you’ve cleared your pipes of any contaminated water check your aerators on your taps for debris and clean them if needed. It’s recommended to also run your dishwasher and washing machine at least two times to ensure the water sitting in those pipes is also clean. It may seem like a lengthy process but there are real health risks associated with contaminated water, so it’s best to be safe than sorry.

What happens after a water main break

Often the initial repair of a burst water main is a temporary fix and the water department will need to come back at a later date to replace the pipe. In this instance you should be receiving regular communications from the water department and if not it’s in your best interest to request information. If there has been damage to your home or business you will need to place an insurance claim and follow through those processes to ensure the damage is repaired. Water main breaks seem more harmless than not but the knock on effects of leaking water can lead to serious damage and health risks.


What looks like just water on the surface can have years of damage below the surface.

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