Australasian Coasts and Ports Conference, 2025, Adelaide
Te Ara Tupua is a New Zealand Transport Agency (NZTA) Waka Kotahi funded resilience project delivered in partnership with Taranaki Whānui ki te Ūpoko o te Ika and Ngāti Toa Rangatira (iwi mana whenua) and Alliance construction and design partners. The partnership is enabled through Te Ara Tupua Mana Whenua Steering Group (MWSG). The Project will create a safe walking and cycling link between Ngā Ūranga and Pito-one, located on the coastal edge of Te Whanganui-a-Tara (Wellington Harbour) and will improve transport resilience by protecting the state highway and main railway line from coastal storms and the effects of future sea level rise and earthquake risk. Construction required significant reclamation and resulted in permanent marine habitat loss. To compensate for the impact on the marine environment, MWSG and NZTA supported the development of a novel reef enhancement adjacent to the Project. Constructed across 5 ha, the reef enhancement comprises 56 concrete pyramid units designed to enhance biodiversity, whilst minimising the seabed footprint. Each unit weighs 23 tonnes, measuring 4 m x 4 m wide and 5 m tall. Units were placed in clusters, spaced specifically to establish ecological connectivity across a wide area adjacent to the shoreline. The reef enhancement provides recruitment surfaces for habitat forming species such as kelp, shellfish and sponges and is expected to attract a diverse range of mobile marine species such as fish and crayfish. A trial kelp translocation onto the reef has also been carried out. Through ongoing monitoring in partnership with iwi mana whenua, the reef’s progress is being assessed against mātauranga Māori (traditional knowledge) cultural indicators and biodiversity compensation predictions. Being the largest concrete subtidal reef enhancement established solely for biodiversity compensation purposes across Australasia, the reef provides significant research and educational opportunities. It is a great example of how mātauranga Māori alongside global science, can ensure our valued marine environment in Te Whanganui-a-Tara is left in the best possible condition, following a major coastal infrastructure project.
