On 1 July 2025, NIWA merged with GNS Science to become Earth Sciences New Zealand.

Freshwater

We provide public information on river, lake, and groundwater conditions across New Zealand including freshwater quantity and quality.

  • New buoy for Wellington Harbour to boost water quality information

    News article
    A buoy with the ability to “phone home” has been deployed in Wellington Harbour today to monitor currents, waves and water quality in the harbour.
  • Hapū joins forces with NIWA in tuna research

    Feature story
    Local hapū and NIWA are working together to find out more about juvenile freshwater eels or tuna in streams connecting to the Wairua River in the Wairoa catchment in Northland.
  • Q&A: Another way to measure river health

    Feature story
    There’s another way of measuring the health of rivers – the health of invertebrate populations that need them, says John Quinn, NIWA Chief Scientist, Freshwater
    and Estuaries.
  • Erica Williams - Where the water is clean

    Feature story
    Erica Williams' story starts with the website of Moerewa School, where pupil Tyra-Lee explains her connection to a very special place in her small Far North town.
  • Raising the bar for swimmable rivers

    Feature story
    The government has released the ‘Clean Water’ package of proposed reforms, aimed at making more of our rivers swimmable. But how is ‘swimmable’ to be measured, and do these measures stack up?
  • Dairy turns the corner

    Feature story
    NIWA's Freshwater and Estuaries Chief Scientist Dr John Quinn believes the dairy industry has been responsive in the tools it has adopted to reduce its impact on waterways.
  • NZ Freshwater Fish Database Help

    Learn how to use the New Zealand Freshwater Fish Database (NZFFD)
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    Riparian management classification

    Management of stream riparian areas - including vegetation and stock access - influences the health of streams and downstream water bodies.
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    Infectious substances

    Waterways can easily become contaminated by pathogens when effluent is discharged nearby.
  • Chemical contamination and agriculture

    What are the potential sources of chemical contamination from agricultural activities?
  • Urbanisation

    Aotearoa’s main urban areas cover approximately 2% of total available land.