Freshwater mitigation systems

Effective systems to manage contaminant losses

Scientists in NIWA’s Mitigation Systems Programme are leading the development, testing, design and modelling of effective mitigation systems, and assisting with their implementation and ongoing performance assessment.

Nutrients, sediment, and microbial contaminants are mobilised from urban and agricultural landscapes and enter streams, rivers, lakes and estuaries. These contaminants can degrade water quality, ecological health, and cultural values.

Science solutions 

NIWA’s research on Mitigation Systems aims to provide effective tools to enable government agencies and landowners to manage contaminant losses. 

Our work includes research on the performance and economic costs of various mitigation systems including riparian buffers, constructed wetlands, detainment bunds, woodchip bioreactors and filamentous algae nutrient scrubbers (FANS).

Understanding mitigation systems

Acknowledgements 

Mitigation systems research generally has been funded by MBIE via research programmes, via Strategic Science Investment Funding (NIWA), and from fee-for-service work done by NIWA for DairyNZ, Overseer Limited, MPI and various regional councils. 

  • 2022_10_CONSTRUCTED WETLAND_mackay_HI__DSC9918.jpg

    Constructed wetlands

    Building back our wetlands
  • Riparian_buffer_cover

    Riparian buffers

    Reducing the flow of nutrients, suspended solids and faecal microbes into waterways by fencing and planting waterways