Using Vac-ex to Safely Reach a Collapsed Drain Beneath Congested Utilities

The Challenge

Galvac was called in to assist with the replacement of a collapsed drain located approximately 2.5 to 3 metres below ground level.

On arrival, it quickly became clear that this wasn’t a straightforward excavation. The failed drain sat beneath a network of existing underground utilities, including multiple services crossing the excavation at different depths.

With so many assets occupying the excavation, access to the damaged drain required a method that offered both precision and complete control.

The Risk

Using conventional mechanical excavation in this environment would have presented several challenges.

Excavator buckets have limited precision when working around densely packed utilities, increasing the likelihood of striking buried assets. Damage to electrical cables, gas mains, water pipes or communication networks could have resulted in:

• Service interruptions affecting surrounding businesses and the local community.
• Expensive emergency repairs and project delays.
• Increased health and safety risks for those working within the excavation.
• Additional excavation to expose and repair damaged services before work on the collapsed drain could even begin.

In a congested utility corridor like this, accuracy isn’t simply beneficial. It’s essential.

The Solution

Galvac deployed one of its vacuum excavation units to safely remove material from around the existing utilities.

Using high-powered air excavation, the team was able to carefully expose each service before continuing beneath and around them to reach the failed drain without disturbing the surrounding infrastructure.

The precision of vacuum excavation meant only the required material was removed, providing a clean working area while maintaining the integrity of the existing services.

Once the collapsed drain had been fully exposed, engineers were able to carry out the replacement with safe, unobstructed access.

The Result

By choosing vacuum excavation, Galvac successfully:

• Safely exposed a collapsed drain located 2.5-3 metres below ground.
• Protected multiple existing underground utilities throughout the excavation.
• Reduced the risk of costly utility strikes and unplanned service disruption.
• Created a clean, controlled excavation for repair works.
• Helped keep the project progressing safely and efficiently.

Why Vacuum Excavation Was the Right Choice

Projects involving deep excavations and congested utility corridors demand a level of precision that traditional excavation methods simply cannot provide.

This project demonstrates how vacuum excavation enables contractors to safely access buried infrastructure while significantly reducing the risks associated with mechanical digging. Where underground services are densely packed, vacuum excavation isn’t just the safer option – it’s often the only practical one.