Air and Hydro Vacuum Excavation
Level A provides vacuum excavation using either air or hydro, providing the right service to meet our clients specific project needs.
About the Process
Both air and hydro vacuum excavation are safe, non-destructive, and cost-effective options for collecting precise information on underground utilities. Air vacuum excavation is a less complex method. It is done by using compressed air to break up the ground soil, which is then vacuumed up into a debris tank. A benefit of using air excavation is that the debris can then be reused to backfill the hole once the excavation is finished. Air vacuum excavation is ideal for smaller scale projects.
Hydro vacuum excavation uses high pressure water instead of air to break up the soil. The soil, which is essentially mud after it has been broken up with water, is then sucked up by the vacuum into the debris tank. The excavated soils cannot be reused to fill the hole, and must be disposed of, sometimes on an off site location. When using hydro excavation, it is helpful to have a water source on site or nearby.
Different types of projects require different methods, and what method is used depends on several factors, such as access to a disposal site, how remote the excavation, the availability of water, jobsite requirements, time constraints, and the goal of the project.
Benefits
Hydro Vacuum Excavation
- Water cuts through the ground faster and digs deeper than air can
- More efficient than air
- Ideal for trenching and large test hole projects
- Preferred when there is risk of encountering groundwater
- Ideal when digging deeper than 10’
- Large boom ideal for remote excavation
- Large debris tank can hold more soil for more efficient digging
- Requires dumping location and water source
Air Vacuum Excavation
- Excavated soil can be used as backfill
- Ideal for test hole projects
- Air causes less mess than water
Call For a Quote:
(800) 752-3151
Restoration
After a test hole is dug and the required information is retrieved, the hole is typically backfilled immediately. When using air excavation, test holes are usually backfilled with excavated soils when possible unless an alternate restoration method is required. Excavated soils are temporarily stored in a tank on the vac truck until they are needed for test hole restoration. They are then compacted back into the hole to restore it to its original state as much as possible. When a test hole is performed on an asphalt surface, the standard repair method is cold patch. We will also restore holes with hot asphalt repair when requested by the client. These are the most common test hole repair methods.
When performing test holes on an asphalt or concrete surface, the asphalt or concrete must be removed before the digging can occur. The most common method of removing this kind of surface is by using a jackhammer. If jackhammering is not preferred, we can also use saw cutting or core drilling to remove the surface. Coring removes the concrete with minimal disturbance and dust. A core is removed from the location where the test hole will be dug, and then restored once the test hole is completed and backfilled.
Additional Information
Our primary application for vacuum excavation is performing test holes on underground utilities.
What is a test hole?
Performing test holes, also known as potholing or “daylighting”, is the process of safely digging exploratory holes in a precise, controlled area for a specific purpose. Test holes consist of digging a vertical hole into the ground in order to confirm the horizontal and vertical location of a utility or underground obstruction. It is also used to clear an area for digging or underground construction.
What is the purpose of test holes?
Digging test holes is method often used to collect Level A data on underground utilities. This includes visually exposing a utility to confirm the exact location, depth, and size of the utility. Test holes are done in the path of proposed trenching, boring, excavating, or any other type of digging into the ground. It is the only way to confirm that the area where the digging will take place is completely cleared of utilities or obstructions.
How deep can we dig?
The standard test hole size ranges from 8”-12” in diameter. Typically, test holes are dug up to approximately 6’ deep. However, depending on the soil type and ground water table elevation, test holes can be dug as deep as 20’ or even deeper in certain situations. We have a fleet of vacuum excavation trucks with a wide range of capabilities to perform test holes of varying depths.
Why use vacuum excavation?
Vacuum excavation is the best way to pothole for numerous reasons, such as safety, efficiency, and convenience. Whether using air or hydro excavation, both will uncover the utility without posing any threat of damage to the utility. There is not a quicker or safer way to gather Level A data on utilities than by using vacuum excavation to expose them. Regardless of whether the utility is close to the surface or deep under the ground, vacuum excavation offers an efficient solution to finding the utility, or clearing the area to the desired depth. With hoses that can stretch up to 200’, our trucks are able to dig on utilities even in places where remote access is required. Vacuum excavation causes minimal disruption to the ground soil; only on the designated pothole locations, which are then restored almost to their original state.