Protecting our streams

Proposed Plan Change 23 and Variations 5 and 6

The proposed plan changes and their associated variations were publicly notified on 12 April 2007. Submissions closed on May 18, 2007. A summary of submissions is currently being prepared for each proposed plan change.

Urban communities, over thousands of years, have generally regarded streams and rivers in different phases:

Initially people were attracted to streams and rivers because they provided life supporting food and water. Many towns and cities have developed along the banks of rivers.

As these towns and cities grew, the streams became convenient tributaries to get rid of rubbish from growing populations.

Many were even buried or piped underground. Today, Auckland’s Queen Street still has a stream running below ground.

In more recent years, besides piping, they have been concreted and straightened to ‘evacuate’ stormwater as fast and efficiently as possible away from growing developed areas. This has allowed greater volumes of water to flow faster as human development has covered over areas for natural absorption of rainwater and encroached onto the streambanks. An example of this in North Shore City is the Wairau Channel.

In the present day, and as we become more environmentally aware, we are realising these watercourses are actually assets which can enhance and beautify towns and cities.

Streams are now not only being retained but restored to a more natural state, and are even being ‘daylighted’ after decades of confinement underground.

Throughout North Shore City’s 13,000 hectares there are more than 50 streams with a total length of over 300 kilometres. These are an asset
that we need to protect with many important functions in an urban environment:

• They can be visually appealing.
• They provide recreational and educational opportunities.
• They provide vital habitats and ‘highways’ for native fish, birds and other wildlife.
• They provide “lungs” breathing fresh air into developed areas.
• They can supply water to some areas.
• They slow down the rush of stormwater during storms.
• They are the natural drainage network.
• They can be transport corridors - for cycling, walking, horse riding or boating.
• A well maintained stream can also adds value to adjoining properties.

This change is about providing a protective buffer between the streams and development.

The riparian margins on either side of a stream are an integral part of the stream and are essential for stream health. They serve the following purposes:

• Providing a protective buffer between development and the stream.
• Allowing the stream to move - a natural occurrence over time.
• Conveying flood waters in heavy rain.
• Reducing flooding and erosion by allowing the flood waters to spread out, reducing the depth and velocities of flows.
• Regulating water temperature by providing shade for the stream.
• Arresting/filtering out contaminants carried towards the stream.
• Providing green linkages and wildlife corridors.
• Offering absorbent surfaces for water soakage.
• Providing food and habitat for wildlife.

We are considering strengthening our regulations to limit development within the riparian margins beside our streams.

North Shore City still has some beautiful streams hidden away in some cases from the public eye, but many have been affected by development.
It is worth protecting what we have and not too late to restore them in future years.

Useful links

Proposed Plan Change 23 and Variations 5 and 6 PDF (90 KB)

For more information

Please contact Susan Andrews, Environmental Policy on:

Telephone:	09 486 8600
Email:	Actionline@northshorecity.govt.nz