Tarawera River

Ngāti Rangitihi, one iwi kaitiaki (local guardian group) of the river, wanted to restore the mauri of Te Awa o te Atua. To understand how to do this, analysis of knowledge from mātauranga Māori and Western science was undertaken and forms the basis of a recovery plan, championed by Ngāti Rangitihi. Critically, this approach has identified solutions that neither body of knowledge could have reached in isolation (Hikuroa et al., 2018). 

The preservation of all aspects of the environment, including human-environment relationships was emphasised (Phizacklea, 2017). ‘The Mauri Model’ was developed, and is a decision-making framework that provides a culturally based template within which Indigenous values are explicitly empowered alongside Western knowledge. The model and indicators are described in more detail by (Hikuroa et al., 2011 and Hikuroa et al., 2018). The concept that mauri fluctuates over time, influenced by human activity, is particularly evident in the Tarawera River (Phizacklea, 2017).

A healthy mauri, or life-supporting force or capacity, is a sign that a river expresses its mana (power, authority). The re-routing (severing) of the natural water flows led to the diminishment of the mauri of the Tarawera River (Hikuroa et al., 2011). Using the Mauri Model, the mauri of the Te Awa o te Atua was determined to be significantly depleted, with the re-routing of the Tarawera River severing the head of the river and stranding the lagoon having had the most negative impact. The Mauri Model analysis forms the basis of planning restoration (Hikuroa et al., 2011). 

Various challenges, including erosion, sedimentation, and changes in water quality, necessitate a multifaceted approach to restoration. This includes erosion protection, sediment and nutrient removal, flood buffering, biodiversity enhancement, and habitat connectivity (Morgan et al., 2012; Peacock et al., 2012).

Flood mitigation strategies, such as the establishment of riparian buffers, draw inspiration from Indigenous perspectives and local iwi, offering cost-effective solutions for managing water quality and runoff issues (Morgan et al., 2012). The restoration and preservation of degraded wetlands provide additional benefits, serving as crucial habitats for culturally significant species like tuna (eels) and harakeke (flax), important to Māori iwi (Peacock et al., 2012).

Strategic site selection for habitat restoration aims to minimise financial and social costs while maximising environmental benefits (Peacock et al., 2012). This project is being developed using a low-cost framework using two quantitative metrics: terrain-land use analysis which identifies areas of ‘high areal pollutant flux’ along with the mauri model decision-making framework which incorporates levels of social, cultural, environmental, and economic factors (Peacock et al. 2012).

In 2022, as part of the Ngāti Rangitihi Claims Settlement Act, a statutory body called the Tarawera Awa Restoration Strategy Group was established. The co-governance group functions as part of the Bay of Plenty Regional Council. Restoration planning is underway.