Air Excavation

Air excavation works on the same principle as hydrovac excavation but substitutes compressed air for pressurized water as the soil-breaking medium. High-pressure air is directed at the ground through a specialized nozzle, fracturing and loosening the soil. The vacuum system then pulls the dry spoils into the debris tank.

The key advantage of air excavation is that the excavated material remains dry and can often be used as backfill, reducing disposal costs and eliminating the need to import clean fill material. Air excavation is also preferred in situations where introducing water could be problematic, such as near electrical infrastructure, in contaminated soil areas, or in cold weather when water would freeze.

However, air excavation is generally slower than hydrovac excavation, particularly in clay soils and compacted materials. The dry spoils can also create significant dust, requiring dust suppression measures. Most contractors consider air excavation best suited for sandy and loose soils, while hydrovac is preferred for clay, hard-packed, or rocky conditions.