About Us

WhenuaTek Ltd is a specialist, locally owned geotechnical, geological, and environmental consultancy based in Ōtautahi Christchurch, delivering services across Aotearoa New Zealand.

Our name expresses the essence of who we are and how we work. Whenua recognises the land not simply as a surface to build on, but as a living, interconnected system of soil, water, ecosystems, and people. It reflects Māori principles of kaitiakitanga (guardianship) and mana whenua, guiding our belief in doing the right thing for the land; making decisions that respect natural systems, manage risk responsibly, and support long-term resilience. Tek represents the technical excellence, scientific rigour, and practical engineering judgement that underpin every solution we deliver.

Our team brings extensive, real-world experience across New Zealand’s most challenging ground conditions. With decades of collective expertise, our geotechnical engineers, engineering geologists, and environmental specialists have delivered projects ranging from residential developments and subdivisions to complex commercial and infrastructure works. This depth of experience allows us to apply sound professional judgement and develop proportionate, buildable, and cost-effective solutions tailored to each site.

We take ownership of every project as if it were our own, providing end-to-end support from initial site assessment and investigation through design, construction, and completion. We deliver fully integrated services with a strong emphasis on early risk identification, clear communication, and consent-ready advice. WhenuaTek is known for its responsive, hands-on approach and ability to provide timely guidance when it matters most. When conditions change on site, we respond quickly and work alongside project teams to deliver the best practical solutions—minimising delays, managing risk appropriately, and aligning engineering outcomes with construction realities.

As a collaborative partner, we work closely with clients, designers, contractors, and regulators to navigate complex ground conditions, seismic hazards, and environmental constraints with confidence. Our advice is grounded in Aotearoa’s unique geological and regulatory environment and delivered with clarity, integrity, and professionalism.

At Whenuatek, we unite respect for the whenua with engineering excellence and practical innovation; supporting your project from initial site assessment through to successful completion, wherever it is located across Aotearoa New Zealand.

Services

We provide expert services tailored to New Zealand's diverse landscapes and regulatory environment, including:

Geotechnical Engineering

Site investigations and soil testing (including in-situ and lab testing)
Liquefaction and seismic assessments
Foundation design, piling, and ground improvement recommendations
Slope stability analysis, land hazard assessments (landslides, erosion, rockfall)
Retaining wall and shoring design
Earthworks supervision and construction monitoring

Geological Services

Engineering geology mapping and assessments
Rock and soil mechanics evaluations
Geohazard identification and mitigation strategies

Environmental Engineering

Contaminated land investigations (PSI and DSI)
Soil sampling, testing, and remediation plans
Erosion and sediment control strategies
Sustainable development guidance and impact assessments

Whether you're developing a single site, planning a subdivision, or tackling a larger project, our Christchurch-based team is here to deliver high-quality results. Contact us today to discuss your needs.

Our Team – Senior Leadership

Raymond Su

BE(Hon), MEngSc (Geotechnical), CMEngNZ, CPEng, IntPE(NZ), APEC Engineer, PMP

Principal Geotechnical Engineer / Managing Director

Raymond is a Chartered Professional Geotechnical Engineer with over 25 years of experience in New Zealand and internationally, providing geotechnical and ground engineering design services across residential, commercial, subdivision, and critical infrastructure projects, including bridges, railway and underground MRT developments. His experience spans the full project lifecycle; from feasibility and site investigation through to detailed geotechnical engineering design and construction monitoring, it includes work on complex hillside developments, deep excavations, and seismic-affected sites with challenging ground conditions such as liquefiable soils, soft compressible deposits, and high groundwater levels. Raymond has a strong background in ground engineering design, including foundations, retaining structures, slope stabilisation, and ground improvement, supported by early-career experience in ground engineering construction, which informs a practical, constructable approach to design. As a Principal Engineer and Project Management Professional (PMP), he works closely with clients, councils, structural engineers, and contractors to provide clear, proportionate, and reliable engineering solutions that support safe, resilient, and consent-ready outcomes.

David Robotham

BSc(Hon), CEnvP, SC

Affiliate Principal Environmental Consultant

David is a Principal Environmental Consultant working in the field of hazardous materials assessment. His 30+ years’ experience comes from working on numerous ventures including major remediation (including asbestos in soil), development and infrastructure projects. Roles include building and site assessments for asbestos, mould and lead paint investigations, full site contamination characterisation, remediation options assessment, production of site management plans and consent application assistance.

Helen Kellett

BSc (Geology), MEngNZ

Senior Environmental Scientist / Engineering Geologist / Senior Associate

Helen brings over 18 years of experience across the geotechnical and environmental sectors in New Zealand and Australia, with a background that also includes mining-related projects. She has strong expertise in land development and commercial construction, including contaminated land assessment, evaluation of risks to human and environmental health, site remediation, and contaminated land management. Helen also specialises in geohazard assessment, earthworks, and geotechnical investigations, supporting projects from early planning through to construction. Her experience across development, infrastructure, and mining environments provides a well-rounded, practical perspective, enabling her to deliver robust, technically compliant, and value-adding solutions that align with regulatory requirements and project objectives.

Zeb Paterson

BSc, PGDipSci, MEngNZ

Senior Engineering Geologist / Senior Associate

Zeb has over 17 years of experience working as an engineering geologist across New Zealand, with a strong track record in both investigation and construction environments. He has provided leadership and technical expertise on major disaster recovery projects alongside EQC, CERA, NCTIR, and other industry leaders. Zeb has overseen large-scale geotechnical investigations and hazard assessments for public and private sector projects. Zeb has led multidisciplinary teams assessing geohazards for linear infrastructure (road and rail) and commercial developments. His expertise includes liquefaction hazard assessment, geological mapping, slope stability, landslides, debris flows, and retaining structures. With substantial hands-on construction experience, Zeb brings a practical, build-focused perspective to geotechnical assessment, ensuring solutions are robust, efficient, and constructible.

Rick Butson

BCom

Senior Geotechnical Technician

Rick Butson is a geotechnical technician with over 15 years of laboratory and field experience across New Zealand and California, specialising in geotechnical investigations and soil testing. As Lead Field Technician, he delivers high-quality field data, including in challenging ground conditions, with expertise in borehole and test pit investigations, in-situ testing, sampling and ground-penetrating radar (GPR) surveys. Rick is known for his practical approach, strong site leadership and mentoring, and his ability to support geotechnical engineers with reliable, construction-ready information.