Our Expertise


Earthtech has an experienced team specialising in hydrogeology. We are able to service projects through all stages from preliminary planning and groundwater investigations through to groundwater modelling, assessment of environmental effects and consenting. Our scope includes groundwater takes for irrigation and municipal supplies through to construction and quarry dewatering.

Our services include:

Recent projects include:

Large Irrigation Groundwater Take from the Kaawa Aquifer

Pump testing and consenting for an 8,060m3/d and 516,000m3/yr groundwater take for irrigation. Monitoring of four observation bores, a shallow well and a stream during pump testing. Development of aquifer parameters and a conceptual groundwater model. FEFLOW model development and calibration. Iwi and neighbour consultation. Assessment of effects relating to neighbours bores and saline intrusion. Non-notified consent granted in January 2015.

Brookdale Groundwater Take, Waiuku

Bonny Glen Regional Landfill, Manawatu

Detailed groundwater investigations to develop an existing local 13ha landfill into a 44.6ha regional facility. Design and supervision of construction of multilevel piezometers to 100m depth. Drilling of inclined bores through unlined portion of the landfill. Water quality sampling and age dating. Development of conceptual model and numerical flow and transport model in FEFLOW. Presentation of evidence at Resource Consent Hearing. Project consents granted in May 2015.

Bonny Glen Regional Landfill, Manawatu

Ihumatao Scoria Quarry, Mangere

Hydrogeological investigations calculation of pumping volumes and assessment of drewdown extent for quarry dewatering to 30m below sea level adjacent to the Manukau Harbour. Assessment of saline intrusion and groundwater related ground settlement. Establishment of a monitoring regime. Consented take of 11,700m3/d and 4,270,500m3/yr. Presentation of evidence at Resource Consent Hearing. Analysis of dewatering monitoring data.

Ihumatao Scoria Quarry, Mangere