Freshwater quality

Habitat degradation and the introduction of exotic plant and fish species have adversely affected kōura populations throughout New Zealand. However, there are a number of measures that we can use to restore kōura populations in lakes, rivers and streams.

New research has revealed that citizen science monitoring of water is a win-win for scientists and volunteers—one gains access to new data, and the other the skills and confidence to become involved in discussions over what is happening to their streams.

At a rough count, 700 million litres of rain runs off the nation’s roads every year. That’s enough water to fill almost 300 Olympic-sized pools.

NIWA’s Catchment Contaminants Loads Model (C-CALM) is a spatial decision support system for planning applications. It estimates annual contaminant loads at the neighbourhood to stormwater management unit (sub-catchment) scale, from diffuse sources, for Total Suspended Solids (TSS) and particulate and dissolved zinc and copper. The estimated load is then adjusted for water treatment.

A summary of the LakeSPI method.

LakeSPI delivers information that is directly applicable to lake-ecosystem conservation and management.

LakeSPI can be used in many ways depending on what the interests or management needs are for a lake.

LakeSPI (Lake Submerged Plant Indicators) is based on the principle that New Zealand lakes can be characterised by the composition of native and invasive plants growing in them, and the depths to which these plants grow.

These are some recent publications related to the causes and effects of water quality degradation programme.

Developing & monitoring technologies, statistical assessment methods & community approaches to assess the state, trends & drivers of water quality.

NIWA has developed a model to assess the potential weed risk of aquatic plants.