Water & Soil Engineer


  • Catchment & River management
  • Water and Soil resources
  • Economic & Environmental assessment
  • Flood & Erosion hazards
  • Irrigation and Drainage
  • Water Quality & Treatment
  • Bridge, culvert and road protection
  • Coastal and wetland investigations

Gary Williams is a self-employed consulting engineer in the field of water and soil engineering.  Over the last 40 years he has worked in or for many different authorities within New Zealand as well as overseas.  He has extensive experience on catchment and river management issues, including hazard assessment, design and construction of works, water and soil resource investigations, the evaluation of environmental effects and economic impacts and the management of assets.  He is a Fellow of Engineering NZ.

He has been involved in major flood mitigation and erosion protection measures, including detailed investigations and design work, on many different types of rivers throughout New Zealand.  He has undertaken a wide range of water and soil resource investigations, covering hydrology, flood warning and hazard assessments, sedimentation processes and gravel resources, coastal processes, environmental character of lakes, estuaries and wetlands, water quality and soil conservation.  He has developed asset management approaches and techniques for river and catchment schemes, and carried out reviews for audit purposes.  His experience in irrigation and drainage covers feasibility investigations, design and construction.  His infrastructure work covers many different services and protection measures.  He has carried out a wide range of benefit–cost studies, as well as assessments for rating and comment on the economic implications of policies.

His water supply and treatment experience is focused on small-scale local systems, which integrate into the natural environment.


In 2013 Gary was elected a fellow of EngNZ for: “his role in designing flood management schemes that harmonise with the natural environment.  He has led the development and dissemination of an approach based on working with nature by understanding natural behaviour and the form of waterways, and then adding channels or fairways that augment rather than modify the natural behavoiur.”

In 2017 he complete a report on his approach to the management of waterways, which summarised this understanding of the natural dynamics of rivers and an approach to management that fits the natural character of river reaches.

The main report can be downloaded as a PDF

Rivers-Article-Natural character