Using resources in efficient and sustainable ways can reduce environmental impacts, relieve demand for raw materials, reduce waste and reduce costs.
This page provides examples of how Waka Kotahi land transport infrastructure projects have been resource efficient. It is intended as a showcase of ideas for project teams on how they can be more resource efficient in their projects and maintenance. We aim to enable and encourage each project and contract to assess and implement the resource efficiency opportunities that make sense within their context.
We are most resource efficient when we re-use demolished pavement and structures, use recycled-content and low-carbon materials where new materials are required, and recover discarded materials for use elsewhere.
Sourcing materials locally also reduces haulage and energy consumption.
We allow the use of recycled materials in our pavement specifications. For example, our M4 Specification for basecourse aggregate allows use of recycled crushed concrete, recycled glass, and melter slag as base course materials. Find out more on our page about what recycled and alternative materials are allowed.
Recycled and alternative materials for transport infrastructure
The Newmarket Viaduct project recycled 22,500 tonnes of recycled crushed concrete and 1,400 tonnes of steel.
The Newmarket Viaduct [PDF, 711 KB]
Christchurch Southern Motorway project incorporated over 120,000 tonnes of recycled crushed concrete and 5,500 tonnes of reclaimed asphalt pavement (RAP) into the pavements. In addition, 66,000 tonnes of low-quality RAP was used in the embankment core fill.
When demolishing the old Park Estate Road bridge in South Auckland, good planning and innovative techniques meant the project team was able to recycle 100 percent of the waste from the demolition, save time and resources, and minimise disruption to the community.
Park Estate Road bridge demolition [PDF, 825 KB]
Wellington’s Aotea Quay upgrade successfully moved and repurposed an unused bridge structure.
Aotea Quay upgrade [PDF, 502 KB]
The Waitangi Wharf replacement in Chatham Islands used an innovative design which required less raw materials, and meant local raw materials could be used, rather than having to ship materials to the isolated island, which reduced the carbon footprint. Almost 100% of the existing wharf structures were repurposed.
Waitangi Wharf upgrade [PDF, 625 KB]
The MacKays to Peka Peka Expressway project provides a useful example of a resource efficiency and waste minimisation plan.
MacKays to Peka Peka Expressway resource efficiency and waste minimisation plan [PDF, 279 KB]
We are moving to LED lighting, because it saves energy and lasts longer, making it more resource efficient.
Sustainability rating schemes provide a consistent method of assessing, achieving, and communicating the positive environmental and social outcomes associated with infrastructure projects, including resource efficiency and waste minimisation.
All Waka Kotahi land transport infrastructure projects with an estimated capital value of over $100 million are obliged to seek Infrastructure Sustainability Council (ISC) certification, and those over $15 million are required to consider it. Some projects than began before September 2020 are seeking Greenroads sustainability certification.
For further information contact environment@nzta.govt.nz
