New Zealanders are in danger of creating “zombie” rivers, not because of nutrient overloading, but because we’re locking our waterways into position between stopbanks and impounding their headwaters.
Professor James Brasington, inaugural holder of the Waikato Regional Council Chair of River Science at the University of Waikato, says we risk the creation of zombie rivers because too often we prevent them from finding their own course and treat them as a means to simply to get excess water out to sea as fast as possible.
He’ll be talking about his research as part of the University of Waikato Hamilton Public Lecture Series, on Tuesday 6 August.
Professor Brasington is a geomorphologist who researches the processes that control the form, structure and function of rivers and their catchments. “If we put our rivers into straight-jackets, they lose the diversity of form and process that are fundamental to the creation of thriving ecosystems,” he says. “Instead we should make space for rivers to erode their corridors, flood naturally in areas that are of less value which will in turn, reduce risks in more sensitive areas. We must work with natural processes to reduce the flood risk and support healthy river ecosystems.”

The river scientist is a pioneer of new technologies that are enabling him and his colleagues to collect novel datasets to better understand how rivers are formed and change over time. “We now can use remote sensing to capture the complex 3D structure of rivers. We use aerial surveys and satellites to create detailed models of rivers that capture the sand and gravel particles that shift and form them through time. This information helps us understand what drives the evolution of rivers through floods and how they create the complex mosaic of habitats within their floodplains.”
Professor Brasington’s research seeks to synthesise these technological advances with numerical models to shed light on how rivers might behave in a future shaped by a changing climate and shifting patterns of land use.
He joined the University of Waikato in late 2017 from Queen Mary University of London and has previously worked at the University of Canterbury in New Zealand, and the universities of Hull, Cambridge and Wales before that. His PhD focussed on catchment modelling in the Nepal Himalaya and since then he has worked on rivers in many mountain environments, including the European Alps and Pyrenees, the high Himalaya, the US Rockies and New Zealand’s Southern Alps.
His research has attracted competitive funding from a wide range of sponsors, including the UK Natural Environmental Research Council, the Leverhulme Trust, the US Department of Defence, UK and New Zealand government departments and their executive agencies, and a broad range of industrial partners. He recently returned from the Tibetan plateau where he and other scientists in an international team were studying the effects of overgrazing on soil erosion and river dynamics.
Professor Brasington’s lecture, Tales from the Riverbank: shining new light on riverscapes, takes place on Tuesday 6 August at 5.45pm in the Academy of Performing Arts at the University of Waikato.