PSI (Pounds Per Square Inch)

Water pressure is one of the most important operational parameters in hydrovac excavation. Higher PSI provides more cutting force for breaking apart hard soils, while lower PSI is used for precision work near sensitive utilities. Hydrovac trucks typically operate between 1,000 and 3,000 PSI, with the ability to adjust pressure from the control panel.

The appropriate PSI setting depends on several factors: soil type, proximity to known utilities, nozzle type, and the specific application. Clay and compacted soils require higher pressures (2,000 to 3,000 PSI), while sandy soils and work near utilities calls for lower pressures (1,000 to 1,500 PSI). Operators should always start with lower pressure and increase gradually as needed.

Excessive water pressure is the primary cause of utility damage during hydrovac operations. While the water jet is much safer than a backhoe bucket, a 3,000 PSI water stream can damage coatings on steel pipes, crack PVC fittings, and cut through polyethylene wraps. Training and experience in pressure management are essential skills for hydrovac operators.