Freshwater - Research Projects

Science Centres: Freshwater

Sustainable Management Framework for Te Arawa Lakes Customary Fisheries

NIWA and the Te Arawa Lakes Trust, with support from the New Zealand Foundation for Research Science and Technology and the Health Research Council, have developed a sustainable management framework for customary fisheries in Te Arawa lakes, as part of a joint 3 year research programme.

Lake Brunner Water Quality

 

A project funded by West Coast Regional Council has increased our knowledge of the role of phosphorus in determining water quality in Lake Brunner

Reintroducing giant kōkopu to Nukumea Stream

 

The giant kōkopu is a native whitebait species considered rare and vulnerable. NIWA is working with Mahurangi Technical Institute and environmental consultancy Boffa Miskell to test the feasibility of reintroducing giant kōkopu to Nukumea Stream, north of Auckland.

Risk Assessment of Contaminants in Traditional Food Sources

 

Gathering, eating and sharing wild kai (food) has always been a very important part of Māori culture and wellbeing - this research project aimed to characterise the risks associated with consuming kai collected from rivers, lakes and coastlines.

 

Long-term fluctuations in river flow conditions linked to the Interdecadal Pacific Oscillation

How will water resources in the water-limited parts of New Zealand, such as Canterbury and Hawkes Bay, look in the future?

Forecasting Irrigation Potential: a case study in the Waimakariri River catchment

Farmers rely on irrigation, but water is a limited resource and little is know about how to manage it best. NIWA has developed a hydrology and soil science model to show how much to water, and when, to get the best results.

Key findings Increasing demands – now and in the future – threaten the sustainability of irrigation for agriculture. The TopNet hydrology model uses ‘scenarios’ to enable experimentation with water supply and demand. With the monitor-match-manage, or 3M scenario, we were able to conserve water and improve the usefulness of irrigation.

Farmers rely on irrigation, but water is a limited resource and little is know about how to manage it best. NIWA has developed a hydrology and soil science model to show how much to water, and when, to get the best results.

Restoring Shellfish Habitats in Estuaries

Changes to the local environment and over harvesting have damaged shellfish populations in many estuaries. These projects examine the most effective way to restore these habitats and allow healthy populations of shellfish to return.

Linking hydrology and ecology in macrophyte dominated streams in Canterbury

Understanding the relationship between hydrological processes and stream ecology is vital for the sustainable management of the water sources that support Lake Ellesmere.

Stream restoration for aquatic invertebrates

Streams play a key role in the ecosystems of New Zealand’s unique landscape. They feed and link together freshwater sources, maintain good water quality and support habitats that sustain our biodiversity. Streams vary in size, discharge, source, function and natural cycle, but each has a pivotal role within its catchment area and provides numerous benefits for wildlife and people.

Habitat requirements of New Zealand freshwater fish

New Zealand's rivers and streams, and the diverse fish that live in them, are worth protecting. But the question of which species prefer to live where was unanswered until NIWA completed this major survey.

Framework for Interoperable Freshwater Models

This project involves the development of a computer-based framework for freshwater models. The framework will be tested to proof-of-concept stage.

Lake Rotorua sediment-capping trial

Many New Zealand lakes are suffering from nutrient enrichment, causing potentially toxic blooms of blue-green algae. Blocking the release of phosphorus from lakebed sediments can be the most effective way of controlling algal blooms. NIWA is testing a range of methods to manage phosphorus release from lake sediments – including sediment-capping agents. 

Dissolved oxygen criteria for fish

A review of dissolved oxygen and fish species in Waikato rivers revealed very low dissolved oxygen levels in some areas, which were impacting local fish populations. NIWA has now produced revised safe levels of dissolved oxygen for fish, which will help inform future environmental planning and resource consents and help to keep New Zealand rivers full of healthy fish.

Restoration of Aquatic Ecosystems

This project aims to increase our knowledge of aquatic ecosystems and their restoration, and apply this to degraded streams, rivers, lakes and estuaries.

Bio-oil from wastewater algae

This project will demonstrate the commercial feasibility of producing bio-oil by the conversion of algae biomass that has been grown in wastewater treatment facilities. In particular we aim to maximise algae production in High Rate Algal Ponds (HRAP) by adding carbon dioxide, and demonstrate energy efficient conversion of algal biomass to bio-oil.

Estuarine water quality: the CLUES Estuary Tool

Many of New Zealand's rivers fail to meet national guidelines for nutrient levels. NIWA has developed the Catchment Land Use & Environmental Sustainability (CLUES) Estuary Tool to predict the effects of land use on estuarine nutrient concentrations.

Restoring Kōaro in the Rotorua lakes

 

The kōaro was once abundant in the Te Arawa lakes near Rotorua in New Zealand’s North Island. NIWA has assessed the viability of restoring this species in the region.