North Sydney Plumber

Installing A New Isolation Valve Without Shutting Down Water to 100 Apartments in Mascot

Everyday Plumbing was recently called to a mixed commercial and residential building in Mascot to carry out some plumbing works. However, before the works could start, our team noticed a significant challenge - the water supply pipe connected to the commercial part of the building had no isolation valve installed. This pipe also supplied cold water to 11 storeys of the building as well as 100 apartments.

Without an isolation valve, if we were to start any plumbing job would need to shut off the entire building's water supply. For a large building like this, the disturbances would be substantial.

To avoid building-wide disruptions and water loss, our plumbing team used specialised pipe-freezing technology to complete the job quickly and effectively.

Why Are Isolation Valves So Important?

Isolation valves are an integral part of any commercial plumbing system. This valve allows sections of the pipe to be isolated for maintenance and repairs.

In this case, having no isolation valve installed meant that there was no safe way to work on the pipe without affecting hundreds of residents. The pipe in question also extended 20 metres up through the building, which created additional safety risks if the pipe needed to be cut.

Using Pipe Freezing Technology to Keep The Water Running

To maintain water throughout the building, our plumbers used a live pipe freezing method.

Pipe freezing creates a temporary ice plug inside the pipe, allowing plumbers to safely isolate a section of the pipework without draining the system or shutting off the water supply.

For this job, we froze the pipe on both sides so we could install an isolation valve.

Upstream Freeze

Freezing the upstream side prevented pressurised water from entering our work area so we could install the new isolation valve quickly and safely.

Downstream Freeze

The downstream side was also frozen. This was an important step as 20 metres of a 50mm pipe remained full of water. Without the downstream freeze, cutting the pipe would result in flooding.

Installing the New Isolation Valve

With both ends of the pipe successfully frozen, a new isolation valve was installed using crimp fittings. Crimp fittings are highly reliable, quick to install, and eliminate the need for hot works and cutting, providing a safer installation method within the confined plant room environment.

The Result

The new isolation valve was installed successfully without interrupting the building's water supply. This building now benefits from a dedicated isolation point, making it easier for future maintenance, repairs and upgrades to be done without disturbing the water supply.

Large Scale Fire Protection and Hydraulic System Upgrade in Mascot

This industrial property needed significant hydraulic upgrades encompassing all of the water service systems, as its existing systems were outdated and posed safety risks to the site's employees. Our team needed to change a lot of items, including installing new fire hose reels, fire hydrants, fire sprinklers and potable water services. This was a big job with lots of moving parts but our team handled it with confidence and completed it in a timely manner.

What Did This Job Include?

Before our plumbers started to dig, they conducted a thorough site inspection to calculate the flow rate for staff and fire protection systems. We then created a 100 metre trench to facilitate the installation of the new underground systems.

To transition from the street mains into the building, we performed precision core drilling through thick concrete foundations and structural walls.

Internally, we utilised a tiered piping strategy:

• Potable Water Systems: We installed high-grade copper pipework suspended from the building purlins using engineered brackets to supply staff amenities.

• Fire Hydrant System: For the primary fire mains, we used Victaulic steel pipework. The grooved mechanical jointing system of Victaulic allows for slight vibration and thermal expansion, which is essential in large industrial sheds like this property. We used electrofusion welding to join these sections. This process uses an electric current to melt the pipe and fitting together, creating a singular joint that is actually stronger than the pipe itself. 

• External Fire Protection: We installed external fire sprinklers, specifically known as drenchers, over glazed sections of the building. These are designed to create a water curtain, protecting the building interior from radiant heat from neighbouring properties.

For the underground main system, we moved away from traditional materials and selected 125mm MDPE (Medium Density Polyethylene). This flexible piping is specifically designed to withstand high-pressure water and gas flow. MDPE is also resistant to soil acidity and corrosion, which takes into account Mascot's acidic soil due to its industrial history.

In addition, two 65mm MDPE lines were installed to service the potable water supply and fire hose reel system.

After completion, all systems were tested and commissioned upon completion to ensure full operational compliance.

Complex Water Leak and Pipe Replacement on Mandible Street, Alexandria

Our plumbers were called to a major water leak beneath Mandible Street in Alexandria. There was water all over the centre of the road and Sydney Water had advised us that it was likely coming from a fire service pipe. Since these pipes are used only for firefighting and rarely inspected, they tend to corrode over time, leading to underground failures and leaks with little to no warning.

As Mandile Street is a busy road and is a mix of residential and commercial areas, the local council required us to complete all work at night to manage safety and traffic flow.

What Our Plumbers Found

Once our plumbers shut down the water supply and exposed the leaking pipe using their non-destructive digging techniques, they discovered that the pipe was severely corroded. The corrosion was so severe that repairs would be impractical, so a full replacement was needed.

Our plumbers got to work, replacing 25 metres of steel pipe from the connection point on the opposite side of the road to the building. We also upsized the copper pipe to allow for a higher rate of water flow in the future as the area grows.

How the Work Was Completed

Works were carried out over multiple nights and included:

• Saw cutting and excavation
• Removing the damaged pipe
• Installing new copper pipework
• Installing hydrants and backflow devices
• Backfilling and restoring the roadway

If you're dealing with an underground leak or can't figure out where the leak is coming from, call our professional plumbers on  (02) 9191 7309 or fill out our online enquiry form today.

Fast Response to a Major Water Main Failure

Our emergency plumbers were called to a large apartment complex in Sutherland, consisting of 125 units. While a contractor was removing a tree, a large log rolled and damaged the water meter and copper pipework.

Since the damaged section was located before the isolation point, the water supply couldn't be shut off using the building's existing infrastructure. This resulted in an uncontrolled leak and significant water loss, needing immediate emergency attention.

The Challenge: A Live 100mm Water Main

When our team arrived on site, water was escaping from the damaged main at a high rate, placing the water supply and surrounding buildings at risk.

With 125 apartments relying on the affected water pipe, it was crucial to stabilise the situation quickly while minimising disruption to the residents. Our priority was to stop the flow of water, prevent further water loss and establish a safe environment so we could conduct repairs.

Emergency Measures to Control the Water Leak

To reduce the flow from the damaged water main, we carefully compressed the larger copper pipe to significantly restrict the flow of the water. The pipe was then folded to create a controlled kink, further reducing the amount of water escaping the damaged pipe.

This temporary solution allowed the situation to stabilise and allowed us to carry out a more permanent repair.

Using Liquid Nitrogen Pipe Freezing Technology

With the leak under control, we used our specialised pipe freezing technology with liquid nitrogen to isolate the damaged section of the pipe.

Liquid nitrogen, cooled to -160°C, was applied to the pipe to create a solid ice plug. This technique effectively stopped the water flow without shutting down the whole water supply. While the pipe was frozen, we cut into it and completed the necessary repairs safely.

Repairing the Damaged Water Pipe

Once the pipe had been successfully frozen and isolated, our team started repairing the damaged section.

The repairs involved:

• Removing damaged sections of the copper pipework
• Repairing the 100mm water service
• Modifying the affected pipework
• Restoring proper water flow
• Pressure testing the repaired section of pipe
• Safely recommissioning the water supply

All of the repairs as well as the emergency response, were completed in three and a half hours.

Maintaining Water Supply to the 125 Apartments

One of the main priorities within this job was minimising the impact on the residents. To achieve this, our team established a temporary water supply from a neighbouring building while the emergency repairs were being finished. This connection provided residents with safe and clean drinking water and also reduced the disruptions on them.