Excavation can sometimes make a huge mess when construction crews dig into the earth to replace, repair, or install new underground utilities.
Backhoes and other excavation equipment usually get trucked in, destroying the ground with massive holes, track marks, and piles of dirt. There is also the risk of potentially miscalculating where underground utilities are, leading to unexpected damage to underground assets and even threats to worker safety.
Crews have increasingly turned to hydro excavation using a hydrovac truck to extract soil from around underground pipes and lines safely, quickly, and with more care toward the environment. The hydrovac process uses high-pressure water to cut into the ground, loosening soil and creating a slurry with dirt, soil, and debris. The mud is then sucked into an excavator truck using a vacuum system and later hauled off to a designated dumping site.
Fast and precise, a hydrovac is more environmentally friendly than other excavation methods and is safer for crews than machine excavation or shovel digging. Water jets up to 3,000 PSI are blasted into the ground, cutting and loosening up soil and grass. It’s important to note that 3,000 PSI is the recommended maximum for the system, as anything higher could potentially cause damage to pipes and lines.
Hydrovac excavation works in many applications, replacing traditional methods with a process that creates minimal disruption for neighborhoods and congested areas.
In most cases, using a hydrovac allows crews to move faster with fewer people and without messing up the excavation site and the surrounding area.
So why should crews choose a hydro excavation over traditional methods of digging?
It’s safe. The risk of damaging underground utilities using a hydrovac is low. The water pressure used during hydro excavation is less than the amount needed to damage lines and pipes, even if there is some shifting over time. With that said, if the water pressure gets too high, it can damage underground assets, so keep an eye on how strong the jet is.
It’s faster than manual labor. Excavation using shovels can be a slow, time-consuming process that requires several workers. Hydrovac work requires fewer people and can be done in a much shorter timeframe, making projects faster and more cost-effective.
It can be done in any climate at any time. If you’ve ever tried to dig a hole during the winter, the frozen ground can make the process a nightmare. A hydrovac can use hot, pressurized water to cut through the soil in cold weather to loosen and liquefy the soil. Then the vacuum truck sucks out the slurry.
It’s a green excavation method. The process only uses water to break up and remove the soil. Once sucked up into the truck, it’s taken to a dumping area for future use.
Although using a hydrovac has several benefits, some considerations need to be accounted for.
Once the soil is sucked out, it can’t be backfilled. In this case, the truck is sucking up mud. Pumping mud back into the trench or hole will make a sloppy mess.
Water conducts electricity. This could pose an issue for the hydrovac operator but can be managed by educating workers about bonding and grounding techniques and maintaining a close eye on possible dangers while on the job.
The slurry has to go somewhere. Once it leaves the ground, the mud has to be trucked somewhere for proper disposal. This requires someone to drive the truck to the designated area, and who knows where it can legally be dropped off.
Hydrovacs are not the only options available to replace traditional excavation techniques.
An airvac uses a similar process but replaces high-powered water with highly compressed air to blast soil. Unlike hydrovacs, which can only hold a certain amount of water, an airvac has unlimited access to air. It’s also safe around delicate utilities and won’t conduct electricity.
On the flip side, because it’s blowing pressurized air, airvacs produce dust and can send small bits of dirt flying all over the place. It also doesn’t work effectively in cold-weather environments and has depth limitations. Finally, using less pressure than water means an airvac will be slower, adding time to excavation projects.
As the saying goes, “an ounce of prevention is worth a pound of cure.”
Tracer wire is a low-cost insurance policy that ensures workers can find underground utilities quickly and avoid costly delays or dangerous situations. When tracer wire is combined with a hydrovac, the result is a safe and highly effective method of installing, repairing, or replacing assets with as little trouble as possible.
Consider tracer wire and hydro evacuation a one-two punch. Tracer wire is fantastic for locating underground pipes and lines. Meanwhile, high-pressure water jets can safely expose utilities without damaging them – even if they have moved.
What does that mean for crews? More efficient digs, reduced days, fewer workers wielding shovels, and less damage to pipes, cables, and other assets.