Dam Engineering

Our team is expert in investigation, design, consenting, construction supervision, safety management, regulatory review, surveillance, through to decommissioning of dams and ancillary infrastructure, such as power stations, spillways, penstocks, bridges, inlet structures, tunnels and roads.

In an evolving context of natural hazards, climate change, and regulations, we provide owners and developers solutions with diverse benefits, while also allowing them to plan for, and efficiently manage, the risks inherent in water detention structures.

Our team relishes working with others. Our engineers, scientists and planners bring specialist and supplementary expertise to collaborative projects, such as stakeholder engagement, fish passage, water quality modelling, liquefaction, arch dam analysis, and seismic hazard assessments.


Services we typically offer include:

Conceptual design and feasibility studies

  • Project definition and value engineering
  • Geotechnical investigations and assessments
  • Hydrological and flood hazard studies
  • Dambreak hazard and Potential Impact Classification
  • Dam engineering
  • Environmental assessment


  • Compliance with environmental legislation
  • Assessment of environmental effects
  • Presentation of evidence
  • Consent renewals
  • Building consents
  • Stakeholder engagement

Dam design and documentation

  • Failure Mode and Effects Analysis (FMEA)
  • Detailed design and documentation
  • Design review during construction
  • Commissioning
  • Dam Safety Management Systems
  • Operation, maintenance and surveillance manuals
  • Emergency Action Plans

Construction management

  • Senior management (both Engineer to the Contract and Resident Engineer)
  • Site supervision

Dam safety management

  • Surveillance, monitoring and evaluations
  • Safety reviews
  • Risk-based frameworks and tools
  • Asset valuation
  • Instrumentation and calibration

Dam rehabilitation and upgrading investigations

Peer review and expert witness


T+T has designed 17 dams in the ICOLD large dam category, with all constructed and operating. We have designed many smaller, yet significant dams (including head ponds) which have been built. Our specialist team has completed over 50 dam safety reviews, dam rehabilitation and upgrade projects.

New Zealand projects include:

Stuart Macaskill Lakes, Upper Hutt 

  • Design and construction monitoring for seismic and seepage control upgrades

Waimea Community Dam, Tasman District

  • Concept development through to detailed design for the 53m high concrete faced rockfill dam and appurtenant structures

Wairarapa Water Use Project, Wairarapa

  • Pre-feasibility and feasibility study of options for storage and optimal use of water resources for the Wairarapa

Ruataniwha Water Storage Scheme, Hawke’s Bay

  • Project scoping and options studies; pre-feasibility and feasibility studies; geotechnical site investigations into providing irrigation water and consent support for the scheme

Waipori Dam Structural Assessment, Lake Mahinerangi, Otago 

  • Geological and geotechnical investigations and structural assessment of this combined concrete gravity and arch dam

Lake Rochfort Hydro Project, Westport

  • Design and construction observation for rockfill dam and penstock intake structure

Whau Valley Dam

  • Design of primary water supply dam for Whangarei District Council. In 2019, Whau Valley Dam celebrated 50 years since commissioning. T+T currently undertake ongoing dam safety audits.

International projects include:

  • Dam safety panel for the design through construction of the 520 MW Huoi Quang project in Vietnam
  • Review consultant through feasibility and into procurement for the 40m high concrete faced rockfill dam Tina River hydropower project, Solomon Islands
  • Sibulan hydroelectric scheme (42 MW) design and construction supervision in Mindanao, Philippines
  • Ambuklao and Binga hydropower schemes sedimentation management studies
  • Detailed design for the 13 MW, two station Tudaya Hydro Power Project in Southern Mindanao, Philippines

 Any questions you can email us here: dams@tonkintaylor.co.nz

Key Project Contacts

Dewi Knappstein (Auckland) (NZSOLD Young Professionals Co-chair, Business Leader Dams)

Tim Morris (Canterbury, Otago, Southland, Westland) (Technical Director Dams)

David Bouma (Waikato, and wider New Zealand) (NZSOLD Management Committee, ICOLD Technical Committee on Levees)

Vicki-Ann Dimas (Melbourne, Australia)

Paul McCallum (Auckland, and wider North Island)

David Leong (Auckland, Northland)

Lance Partner (Bay of Plenty)

Bryn Quilter (Waikato)

Casey Giberson (Waikato)

Tung Hoang (Wellington)

Neville Laverack (Nelson, Tasman, Marlborough)

Dominic Fletcher (Canterbury, Otago, Southland, Westland)