“Hydrogeology is about geological environments that control the occurrence of groundwater” Freeze and Cherry (1979). We can estimate the quality and volume of groundwater that you may be able to obtain from your site, how the groundwater may affect your site development, and the best way to harvest that water.

Our team of expert hydrogeologists provide a range of technical and planning services for the management of groundwater resources. The team specialises in complex, multi-disciplinary projects with expertise in engineering hydrogeology, aquifer characterisation, contaminant hydrogeology, groundwater monitoring, numerical modelling and peer review services. The hydrogeology team comprises a group of innovative professionals providing a range of technical services to clients across New Zealand, Australia, and the wider Pacific region.

T+T and Lutra team up for safe drinking water

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Preliminary groundwater regime assessments

  • Desk study reviews and site history investigation

  • Preliminary risk assessments and walkover inspections

  • Feasibility assessments


  • 2D/3D groundwater flow and solute transport

  • Contaminant fate and solute transport modelling

  • Dewatering

  • Drawdown

  • Saline intrusion

  • Stream depletion

  • Seepage analysis

  • Dewatering assessments

  • Wellhead protection and capture zone analysis

Groundwater resource characterisation, assessment and protection

  • Municipal water supplies

  • Catchment Sanitary Inspections

  • Irrigation assessments

  • Well and spring source protection zones

  • GIS based risk assessment tool

Land development projects

  • Drawdown-related settlement effects analysis for infrastructure projects (e.g. basements, foundations, pipelines, tunnels, dams)

  • Dewatering assessments

  • Groundwater supplies for drinking, irrigation and industrial use

  • HVAC - using groundwater for heating/cooling systems and Municipal, Industrial and hazardous waste facilities

  • Containment facilities design

  • Determine private landfill trigger levels for regulatory compliance

Site characterisation, groundwater sampling and monitoring

  • Well design installation and development

  • Geological logging during bore drilling

  • Design, supervision and analysis of pumping tests, slug tests, packer tests

  • Resource consent compliance monitoring

  • Groundwater and surface water interaction characterisation

  • Development of hydrogeological conceptual models

  • Water balance and catchment analysis

  • Dye tracer testing

  • Data handling and analysis

Review services

  • Peer review of hydrogeological and modelling reports

Regulatory liaison

  • Strategic advice to local authorities

  • Community consultation

  • Technical support for resource consent applications

  • Preparation and presentation of expert evidence

Key projects:

Havelock North:

Technical investigations to determine the source of the Campylobacter outbreak which affected approximately 2000 Havelock North residents, and originated from the HDC Brookvale Rd bore field. Tonkin + Taylor’s input included extensive assessment of potential bacteriological sources within the catchment, contaminant fate and transport modelling and risk assessment, dye tracer tests, and numerical groundwater modelling. T+T completed detailed reporting in regard to those investigations, and prepared statements of evidence, and appeared for the Council at the Government Inquiry into the Havelock North Water Supply.

HVAC, Christchurch:

Heating, ventilation and air conditioning (HVAC) systems using groundwater as a source of energy for the heating or cooling of buildings have become increasingly common in new large scale commercial buildings in Christchurch CBD. Tonkin and Taylor have been involved with a number of projects involving the drilling of deep abstraction wells and shallow reinjection wells for HVAC systems and providing the site specific information on the groundwater regime to support resource consent applications for the operation of the HVAC systems. Our technical expertise supporting this project work includes provision of the drilling specification and design of the pumping test programme through to pumping test analysis, well interference assessments and groundwater modelling to determine the mounding effects and potential temperature plumes associated with groundwater reinjection.

Key Contacts

Leon Pemberton - Discipline Manager

Tony Cussins - Technical Director

Hydrogeology Team

  • Mei Wang, Principal Hydrogeologist - Melbourne

  • Tony Reynolds, Senior Hydrogeologist - Auckland

  • Chris Shanks - Auckland

  • Sally Lochhead - Christchurch

  • Hannah Ross - Auckland

  • Kevin Ledwith - Auckland

  • Ryan Tutbury - Hamilton