Riparian Enhancement

The gold mining industry in New Zealand is all 'take take take' and never gives anything back. It's got a terrible environmental reputation and the operations destroy habitats and natural environments. Well ... no. Here's one small example. (We have more.)

Waterway Protection: Riparian Enhancement
Waterways are an important part of our environment and community. They form part of our history, culture, recreation, and economy. The sustainability of waterways is directly related to how they are currently used and managed. To ensure continued water quality and quantity we need to ensure that we manage waterways wisely.

An important part of any waterway system is the riparian margin. These are the strips of land that run either side of rivers and streams from the edge of the floodplain to the waterway itself.

Over much of the country riparian vegetation has been cleared for farming. This has added to the pressure being placed on water resources. Streambank erosion releases sediment and nutrients. Livestock grazing on streambanks places animal waste directly into the water, degrading water quality for downstream users.

Many local and regional councils encourage the retirement of riparian margins. That is they advocate fencing off river and stream banks so that they are no longer grazed by stock and then protecting the margins by re-establishing suitable vegetation.

Benefits of Riparian Enhancement
Riparian retirement is the most beneficial option for improving water quality.

A retired riparian strip:

• reduces silt entering waterways by helping prevent bank collapse
• prevents fouling of water by stock
• helps wetland areas inside the fence to purify water by trapping silt
  and stripping nutrients from runoff.
  

Other advantages of riparian retirement include:

• River bank stabilisation
• Reduced flood impact
• Wetland conservation
• Indigenous land habitat restoration
• Improves aquatic habitat
  
  
  Right: Community volunteer groups and Newmont Waihi Gold staff plant young Kauri along a recently retired section of the Ohinemuri River in 2006. Established riparian planting can be seen on the opposite bank.
  
  

Retirement Issues
There are disadvantages to the farmer if retired riparian margins are not managed. Species such as gorse and blackberry may regrow, riparian areas can act as a weed source, and pests such as rabbits can find the area attractive. These problems can all be avoided by putting in place a sustainable riparian management plan. Such a plan details fencing, establishing and maintaining appropriate vegetation, and minimising any adverse effects on the waterway from land use inside the margin.

Some councils offer to prepare riparian management plans as a free service or supply seedlings for riparian planting at cost. Environment Waikato has implemented a very successful Clean Streams programme that focuses on effective riparian management. They can be contacted for further details.

Riparian Enhancement at Newmont Waihi Gold
Nearly 20 years ago environmental staff at Martha Mine recognised the need to preserve riparian areas and implemented a comprehensive plan to progressively retire these. Since 1992 riparian margins on company owned land along the Ohinemuri, Ruahorehore, smaller tributaries and associated wetlands have been gradually retired from production, fenced and planted.

To date over 350,000 native shrubs, grasses, flaxes and trees have been planted. All the plants are eco-sourced from local seed to conserve the local gene pool, and grown locally. This has created a local business and continues to provide employment.

Experience has shown that it takes about four to five years for an area to become maintenance free and self sustaining. It hasn’t all been easy. Some flood events have seen large clean-up efforts become necessary. But it has been well worth the effort, and it’s all part of our philosophy and continued commitment to the environment and our community.

For more information on water management at Newmont Waihi Gold click here.