Key points
Nitrogen and phosphorus are both plant nutrients. In excessive amounts, these nutrients can cause nuisance growths of water plants and algal blooms. This can determine how suitable the rivers are for swimming, and for plants and animals to live in. Environment Waikato’s monitoring programmes and our records of nutrient inputs from moderate-to-large point sources, tell us about the amount of nitrogen and phosphorus entering four large rivers in the Waikato region.
- The estimated amounts (loads) of the plant nutrients nitrogen and phosphorus from ‘natural’ sources are relatively low.
- Nitrogen loads from point sources are also relatively low.
- Non-point source loads of nitrogen from developed land are relatively high.
- Loads of phosphorus from point sources and from non-point sources are usually similar. Until recently, the point source load of phosphorus to the Waitoa River was particularly high.
Source: Environment Waikato
What agencies are doing
- Environment Waikato monitors the nutrient levels in rivers to update this indicator and to assist with policy making and resource consent decisions.
- Environment Waikato has classified different waterbodies into different management classes. We have established these classes to manage water use and protect water quality values.
- Environment Waikato manages and requires the monitoring of resource consents to discharge wastewater to rivers, or to dam or divert rivers and streams.
- We support Care groups in the Region that are involved in riparian management such as planting and fencing.
- Over 217 Rivers and Us programmes involving more than 100 schools have been run.
- Environment Waikato's Clean Streams project provides advice and financial support to encourage and support farmer efforts to reduce the impacts of farming on waterways through fencing and planting waterway margins.
- We provide environmental information, including practical land management guidelines.
- We support voluntary guidelines and codes of practice such as the NZ Fertiliser Manufacturer’s Research Association’s Code of Practice for Fertiliser Use (code of practice).
What you can do to help
- Fence off streams, rivers, swamps, wetlands and seeps to prevent stock access.
- Plant banks of waterways to help stabilise the banks and trap nutrients.
- Make sure dairy shed effluent irrigators are operating effectively and are moved frequently to prevent ponding and runoff into waterways.
- Avoid break-feeding or mob-stocking close to waterways, especially in wet weather.
- Form a Care group with your neighbours to discuss and implement better land management practices to protect your local river and stream.
- Install stormwater detention areas in new subdivisions to improve water quality (less silt and animal faeces reaches the rivers and streams). Find out more about activities requiring consents from Environment Waikato.
More information
More detail on this indicator, including how and where this information is collected, is available here.
What we want to achieve
The community outcomes we are seeking to achieve by monitoring the sources of nutrients in rivers are:
- The iconic landscapes and natural features of our environment define and sustain us. We respect and celebrate them as taonga.
- Our natural environment is protected and respected. Its ecological balance is restored, its air, soil and water quality is improved and its native biodiversity is enhanced.
- The traditional role of iwi and hapu as kaitiaki is acknowledged, respected and enabled.
- Our region’s waterways have consistently high water quality.