Intergroup has five years of experience with onshore hydro excavation in New Zealand. Hydro excavation uses high-pressure water instead of manual chipping. It is more precise than standard excavators and faster than digging.

The gentle giants of excavation, hydro excavators:

  • Will not damage tree roots – ideal in urban environments
  • Reduce risk of services strike – has been made mandatory in overseas cities (e.g. Brisbane following a three-day power outage)

Powerful vacuums then remove the excavated clay and soil, gravels, base course, and rocks (ranging to the size of a fist). With hydro excavation, excavation risks get ‘washed away’.


  • Open trenching – without prior potholing
  • Potholing and investigation
  • Services identification/confirmation
  • Working around tree roots/services
  • Lighting pole installation
  • Pile drilling


Cost-Effectiveness, Speed and Efficiency

  • At least three times faster than hand digging
  • Confident drilling around tree roots and services
  • No need to waste time and money on potholing prior to open trenching
  • One vehicle does it all – no need for excavators, dump trucks and hand diggers
  • Greater capacity water and waste holding – can run all day without leaving site
  • Experienced crews adjust pressures and methods for optimal productivity

Risk Reduction

  • Greater precision than standard excavators
  • Won’t cut through services – reduced risk of electrocution/explosion and the cost of service interruption
  • Won’t cut through tree roots – resource consent compliance and arborist satisfaction
  • Full range of safety features: GPS, beacons and alarms, earthing rods and wires, gas detectors (as required), and rubber-insulated top


  • All waste contained in vacuum tank – no mess in residential/commercial areas
  • No complaints about services interruptions to homes, shops and offices
  • Dust all but eliminated
  • No harm to heritage/protected trees


Ultra-Fast Broadband Network

  • Excavation for open trenching without the need for initial potholing

Alfred Street Upgrade – Auckland

  • No damage to heritage Plane Tree roots

Victoria Park Tunnel – Auckland

  • Exploratory holes uncovered two unknown power lines
  • Removed risk of strike to main fibre optic cable connection with Australia
  • Numerous archaeological finds without any damage

Lighting Pole Installation – Kumeu, Henderson and Otahuhu

  • No augering or service damage

“You can’t fault the hydro excavators. They make my life easier. You don’t have to clear any mess away. They eliminate the need for diggers and productivity is much faster than hand digging – without a doubt. There’ve been no strikes to services at all. We’ll be using hydro excavators for the full eight years on this job. I see Council making hydro excavators for potholing compulsory in future. It just eliminates the risk.”

Cain Simpson,
Leighton Contractors

1. Powerful Water Jet – Optimised pressures and flow rates for maximum cutting with minimum waste & hand held for precision
2. Large Water Tank System
  • Sufficient capacity to last a whole day without stopping
  • Refillable from road hydrants if required
3. Manoeuvrable Boom
  • 360° rotation for flexibility
  • Telescopic for maximum reach – and the ability to attach extra hoses as required
  • Radio controlled for safety
  • ≥27° of mercury vacuum loading
  • Effective size ranges from 150mm to 20cm for variable power and precision
  • Optimal airflow to prevent blockages
  • Head attachment for pile drilling/street light bases (custom designed by Intergroup)
4. Large Hopper
  • All vacuumed solids and liquids contained in 8-15m3 capacity vacuum tank
  • Shuttle vacuum truck for onsite unloading