A Beginners Guide to Vacuum Excavation

As with any industry, those involved in it easily get into the habit of using jargon and technical terms and assume that everyone will know exactly what they are talking about!

A fleet of vacuum excavator trucks

Industry Jargon

Jargon that helps industry communication-it’s not always the case, so, here at VAC Group we’re always happy to provide an explanation of different processes, assess their benefits, how they are best used and the like. Our teams got together to build together a guide to the process of and benefits to vacuum excavation – also referred to as hydro excavation.

What is vacuum excavation?

It’s a process with a much longer history than many might imagine. It’s believed that around 1850 miners in California worked to remove land masses – and get at the gold – by using steam pumps to target pressurised water. Move forward a century and miners in cold, frozen climates, such as North America, looked for an alternative to standard digging, impossible for much of the time in working locations that were often virtually tundra. Hydro excavation, using heated water, was an effective solution. As the processes became more refined, this process increasingly became a go-to solution for many excavation projects across Australia and elsewhere – especially when non-destructive digging is required.

How does hydro excavation work?

Modern vacuum excavation processes combine high-pressure water with an air vacuum. The former cuts into and breaks up the soil; the latter then removes the slurry that’s produced from the location to a debris tank. The vacuum source is provided in one of two ways: either through a positive displacement blower or a fan system. The latter choice is easier to use. It effectively moves huge amounts of air; this means it delivers faster excavations and is usually both lighter and less expensive than the alternative displacement blower systems. This is an effective choice for hydro excavation processes.

Where can you use hydro excavation?

In many construction projects, both underground facilities and subsurface utilities are key elements. Vacuum excavation has provided a generally safer way of meeting these needs. It leads to less traffic, and accompanying congestion, in key excavation locations, mainly because the actual equipment can be positioned at a distance. Hydro excavation is frequently used for sign or pole installation, sewer or pipe rehabilitation (less likelihood of costly and time-consuming pipe punctures). In landscaping terms, there is much less disturbance of the surrounding soil than by other methods, leaving it more firmly compacted.

What is vacuum excavation used for and what are the key benefits?

Some of these are clear from the uses we’ve already discussed. Safety is always a front and centre priority in any project, and this system’s accuracy has led to less accidents or injuries for those involved in the work, and also for others who may be active on the site for a variety of reasons. Matched to that is a process that is accepted as being less damaging than possible alternatives, such as the more traditional digging or backhoe methods. This includes less damage to underground pipework, cabling, and power or other lines.

It’s clear to see that a safer and less damaging system can lead to a reduction in insurance and liability cover, as well as fewer leaks or other repairs or replacements. The alternatives are also more labour intensive and add much more in the way of time needed for project completion. The work carried out is more precise and accurate, and there is less need for back-filling. This all leads to a much happier bottom line!

A less tangible, but equally important benefit, is that mining, construction, and other projects that operate more effectively in this way enhances the reputation of the company completing the work. These, and other plus points, including the ability to continue operating across a range of different weather conditions, have led to vacuum or hydro excavation becoming the most preferred method in locations and projects where excavation work is required. It’s also easy to make a case for this process being more environmentally sympathetic than the more destructive alternatives.

How does a vacuum excavator or hydro excavation truck work?

Using superb vacuum excavation trucks like the Vac-U-Digga 3,000L unit or 6,000L unit, it becomes a one-step simple process. The truck uses high pressurised water to break up dirt, clay, sand, grass, mud, rocks, or compound surfaces. The vacuum system delivers a high-volume airflow through the suction fans, powered by the vehicle’s engine. This delivers the level of suction needed to pull the water and other material into the intake nozzle, through the hose, and then into the storage holding tank for later safe disposal.

The air itself is then micro-mesh filtered and released back into the atmosphere. Tools, such as an air lance, can even be used to help free stubborn ground. This process, with the vital maneuverability of the trucks, and key components such as hydraulic booms, can be used for digging in confined spaces, evacuation under a standing structure, tree root removal, trenching, and many other situations. It also helps prevent other problems, associated with traditional digging, such as soil entering a storm water system.

Looking for reliable hydro excavation contractors?

If you have decided that this less invasive, swifter, safer, cost-effective, high precision, hydro excavation or vacuum excavation process is the best answer to meet your digging needs, then the next question is this: who best to deliver the services you require?

Ask around and you’ll likely find us to be your best choice. We operate across a large portion of Australia, from Brisbane to Adelaide, Sydney to Melbourne, and many other locations throughout Australia. Our vacuum excavation fleet, complete with a hugely experienced team can tackle any hydro excavation task – no matter how difficult. Indeed, we are known to boast the southern hemisphere’s largest fleet of Aussie manufactured, owned and operated Vac-U-Digga units, with a wide range of capacities! To find out more about our fleet and capabilities, simply click here for access to our extensive Vac Group.

Contact VAC Group Today!

If you are looking for reliable vacuum excavation, utility location and non-destructive digging services in Brisbane, Sydney or Melbourne, give us a call.

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3000 Litre Hydro Excavation Unit

Our 3000 litre hydro excavation unit for hire is readily available for dispatch right across Australia. Find out more.

6000 Litre Hydro Excavation Unit

Our 6000 litre hydro excavation unit for hire is readily available for dispatch right across Australia. Find out more.


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