Biodiversity projects
When Europeans settled New Zealand, they regarded braided rivers as ‘normal’ rivers surrounded by useless swamps and undeveloped land. Water was seen as an endless resource that could be used to generate power and to eradicate biodiversity in favour of agriculture. In spite of this, the braided rivers frequently did what they had done for millions of years: filled their braidplains with water, flushing out any pollutants, and delivering enough gravel to extend the coast seaward. Viewing them as hazard, the once wild rivers were treated as an enemy to be tamed. Wetlands that had once acted as natural kidneys and provided endless kai were drained and concreted over to become towns and cities like Christchurch, Woodend, Rangiora, and Kaiapoi. Everywhere else, thousands and thousands of hectares of braidplains were lost to agriculture , primarily to support the dairy industry which, perversely, intensively polluted the rivers. To protect towns and farms from an enemy of our own making, we then engineered stopbanks, levees, and bunds, and planted invasive trees like willows that sucked up water like camels. Once life-giving pure clean water now costs millions of tax and ratepayer dollars to make it ‘drinkable’—if you ignore international standards on what’s regarded as drinkable in terms of nitrates. The extraordinary biodiversity of the braidplains that once provided these essential life-supporting ecosystem services hand that we now desperately need to mitigate climate change, have been methodically destroyed.
This story is not colonial history. It’s still happening. And recent (2018) case law has further depleted the legal definition of a braided river; scroll down to see the redefined Ahuri River.
Neverthless, people, councils, and community groups are fighting back, determined to save and restore the biodiversity of these incredibly rich and globally rare ecosystems.
Key actions
To see specific biodiversity projects on rivers, please click on each of the rivers. You can also check the ten Canterbury river and water management zones (this website) and the online mapping tool, Canterbury maps. Several agencies and groups have or are currently working towards submission to amend the legal definition of a braided river under the Resource Management Act.
Weed encroachment – control work
Coordination between Environment Canterbury (ECan), Department of Conservation (DOC), LINZ, landcare groups, landowners, and river care groups such as the Ashley Rakahuri Rivecare Group to develop and implement strategic, landscape scale operation to control and remove invasive weeds.
Predators – control work
Similarly, multiple large scale collaborative projects between ECan, DOC, Universities, LINZ/Boffa-Miskell, and rivercare groups, and in conjunction with Predator Free New Zealand. Many small scale projects not mapped here are being undertaken as part of the overall ‘PredatorFree 2050’ initiative.
Habitat enhancement and investigations
Multi-agency field research along rivers such as the Lower Waitaki and Clarence rivers have been testing methods to enhance habitats, primarily islands, by removing weeds and increasing the distance that predators must swim to reach them.

Policies to protect & restore
Canterbury Water Management Strategy goals and targets
- Braided Rivers
- Increasing bird habitat
- Active management for indigenous plants and wildlife habitats
- Natural character
- Ecosystem health/ biodiversity improving
Canterbury Biodiversity Strategy goals
- Protect and restore habitats and ecosystems
- Enhance public awareness and understanding
- Improve knowledge and information
Regional strategic priorities
- Accelerate regeneration of the natural environment

The Aururi River braidplain
Further information & references
- Braidplain or floodplain? What’s the difference and why does it matter?
- Resource Management Act 1991
- Canterbury Water Management Strategy
- Natural Character of Braided Rivers
- Targets and Goals (October 2020)
- Updated CWMS Strategic Framework document (September 2019)
- Land Air Water Aotearoa LAWA – easy to find data on all New Zealand rivers
- ECan document library: enter the river or catchment name in the ‘keywords’ search field
- DOC catalogue of scientific publications: enter the relevant search terms in the ‘search’ dialogue box. You may need to vary your search, for example ‘black stilt’ gives far more results than ‘kaki’ or ‘kakī’
- Land Information New Zealand (LINZ) Biosecurity Control Programme (weed clearing, rabbit and wallaby culling)
- 2021: Drinking water nitrate limit 11 times higher than it should be – health expert; Radio New Zealand
- 2020: Rethink over nitrates as Government orders review into link with cancer; Stuff
- 2019: Productivity Commission: Local government funding and financing (financing and management of rivers given the climate change risks)
- 2019: (ECan) Pompei, Grove & Cuff; Monitoring extent of available habitat for indigenous braided river birds in Canterbury – a 2012 Baseline
- 2019: DOC; Management and Research Priorities: terrestrial invertebrates, lizards, terrestrial native plants, terrestrial weed invasions, and geomorphology, wetlands, river mouths and estuaries
- 2018: ECan; Braided Rivers; natural characteristics, threats and approaches to more effective management
- 2017: NIWA; Modelling vegetation-impacted morphodynamics in braided rivers
- 2017: Hughey; Keynote address: Local, regional, national and international aspects of braided river management (BRaid seminar)
- 2017: (DOC) Maloney; Opportunities and priorities for future braided river conservation (BRaid seminar)
- 2017: (DOC) O’Donnell; Values and management of lowland braided rivers for birds (BRaid seminar)
- 2016: BRaid; Teaching resources (PDF) or (iPad)
- 2016: Forest & Bird; Important Bird Areas on Braided Rivers – links to list of 3-7 page PDF files, by river name. These were extracted from Forest & Bird’s 177-page 20Mb file on all rivers, lakes, and coastal areas.
- 2016: DOC; Management and Research Priorities for New Zealand Braided Rivers
- 2016 (DOC) O’Donnell; Opportunities and priorities for future braided river conservation; BRaid workshop
- 2015: ECan; Land Use Change on the Margins of Lowland Canterbury Braided Rivers 1990-2012
- 2012: Salmon; Canterbury Water Management Strategy–a case study in collaborative governance. Ecologic report prepared for the Ministry of the Environment.
- Hearnshaw et al (undated): Ecosystem Services Review of Water Storage Projects in Canterbury: The Opihi River Case
- 2007: DOC; Braided River Ecology: a literature review of physical habitats and aquatic invertebrate communities