Deep Dig

Deep dig hydrovac excavation is required when utilities or pipeline infrastructure is buried at significant depth, or when the project requires a deep foundation excavation or environmental soil sampling. Depths of 15 to 25 feet or more are achievable with properly equipped hydrovac trucks, though efficiency decreases as depth increases due to friction loss in the dig tube and the additional lift required by the vacuum system.

The primary technical challenge of deep digging is maintaining adequate vacuum at the bottom of the excavation. As the vertical distance from the dig tube tip to the vacuum inlet increases, the blower must work harder to lift the slurry. Positive displacement blowers generally outperform centrifugal blowers for deep dig applications because they maintain suction performance across a wider range of conditions.

OSHA regulations under 29 CFR 1926 Subpart P apply to any excavation deeper than 5 feet. While hydrovac excavations are generally narrow enough to be exempt from shoring requirements, the competent person on site must evaluate soil conditions and determine whether cave-in protection is needed. Workers should never enter a hydrovac excavation deeper than 5 feet without proper protective systems in place.