Draft OARC Regeneration Plan - 2: Living with water

Porritt Park in flood (1 in 100-year event), March 2014

Objectives: Demonstrate how to adapt to the challenges and opportunities presented by natural hazards, climate change and a river’s floodplain.

Establish a world-leading living laboratory, where we learn, experiment and research; testing and creating new ideas and ways of living.


The regeneration of this area provides a unique large-scale opportunity to integrate the management of land, water and natural hazards and demonstrate new approaches to living with water. It is something the rest of the world will be watching.

Working with nature

The National Policy Statement for Freshwater Management recognises Te Mana o Te Wai (the integrated and holistic wellbeing of the water), which seeks to provide for Te Hauora o Te Taiao (the health of the environment), Te Hauora o Te Wai (the health of the water body) and Te Hauora o Te Tangata (the health of the people).

Ōtautahi/Christchurch was built on swamps and dunes around the Ōtākaro/Avon River so the city’s water and land have always had a close relationship. Large-scale works drained the swamps to build homes and businesses, with pipes and drains conveying rainwater from our streets and roofs to the nearest river.

This approach led to a steady decline in the health of our rivers and waterways as contaminants are washed into the river instead of soaking into the ground.

The regeneration of this area provides an opportunity to demonstrate what it means to manage land, water and hazards in an integrated way and work with nature to uphold Te Mana o Te Wai.

Improving water quality

Approximately a third of the Ōtākaro/Avon River stormwater catchment (2,600 hectares) drains through the Regeneration Area, presenting a one-time opportunity to retrofit stormwater treatment and begin to reverse the decline of water quality. The construction of detention ponds and wetlands to treat stormwater would improve water quality as well as providing habitat, recreation and educational opportunities.

Diagram showing the extent of the Ōtākaro/ Avon River catchment draining through the Regeneration Area

Managing the river when storms come

Large parts of east Christchurch are low-lying and vulnerable to flooding. Temporary stopbanks extending the length of the Regeneration Area currently reduce flood risk to about 4,000 houses. Over time these stopbanks need to be replaced.

Permanent stopbanks can be built further back from the river on more stable ground, enabling a reduced height to offer the same level of protection. This allows for more naturalised river edges to provide a buffer against flooding and enhancement of mahinga kai values by improving habitat for native species such as īnanga (whitebait). Stopbanks can also be constructed to support other uses, such as recreational activities and ecological restoration.

Getting ready for sea level rise

Ministry for the Environment guidance is to expect between 0.65 and 1.9 metres of sea level rise over the next 100 years, which will gradually cause groundwater to rise, increase the frequency of flooding, and change the ecology of the river and surrounding land.

Stopbanks should be set further away from the river’s edge with wider foundations that allow the stopbanks to be raised over time to adapt to sea level rise.

Objectives: Demonstrate how to adapt to the challenges and opportunities presented by natural hazards, climate change and a river’s floodplain.

Establish a world-leading living laboratory, where we learn, experiment and research; testing and creating new ideas and ways of living.


The regeneration of this area provides a unique large-scale opportunity to integrate the management of land, water and natural hazards and demonstrate new approaches to living with water. It is something the rest of the world will be watching.

Working with nature

The National Policy Statement for Freshwater Management recognises Te Mana o Te Wai (the integrated and holistic wellbeing of the water), which seeks to provide for Te Hauora o Te Taiao (the health of the environment), Te Hauora o Te Wai (the health of the water body) and Te Hauora o Te Tangata (the health of the people).

Ōtautahi/Christchurch was built on swamps and dunes around the Ōtākaro/Avon River so the city’s water and land have always had a close relationship. Large-scale works drained the swamps to build homes and businesses, with pipes and drains conveying rainwater from our streets and roofs to the nearest river.

This approach led to a steady decline in the health of our rivers and waterways as contaminants are washed into the river instead of soaking into the ground.

The regeneration of this area provides an opportunity to demonstrate what it means to manage land, water and hazards in an integrated way and work with nature to uphold Te Mana o Te Wai.

Improving water quality

Approximately a third of the Ōtākaro/Avon River stormwater catchment (2,600 hectares) drains through the Regeneration Area, presenting a one-time opportunity to retrofit stormwater treatment and begin to reverse the decline of water quality. The construction of detention ponds and wetlands to treat stormwater would improve water quality as well as providing habitat, recreation and educational opportunities.

Diagram showing the extent of the Ōtākaro/ Avon River catchment draining through the Regeneration Area

Managing the river when storms come

Large parts of east Christchurch are low-lying and vulnerable to flooding. Temporary stopbanks extending the length of the Regeneration Area currently reduce flood risk to about 4,000 houses. Over time these stopbanks need to be replaced.

Permanent stopbanks can be built further back from the river on more stable ground, enabling a reduced height to offer the same level of protection. This allows for more naturalised river edges to provide a buffer against flooding and enhancement of mahinga kai values by improving habitat for native species such as īnanga (whitebait). Stopbanks can also be constructed to support other uses, such as recreational activities and ecological restoration.

Getting ready for sea level rise

Ministry for the Environment guidance is to expect between 0.65 and 1.9 metres of sea level rise over the next 100 years, which will gradually cause groundwater to rise, increase the frequency of flooding, and change the ecology of the river and surrounding land.

Stopbanks should be set further away from the river’s edge with wider foundations that allow the stopbanks to be raised over time to adapt to sea level rise.