
Cover Image:
The full name of the Mimi River is Mimitangiatua. The river was also known as Te Wai o Mihirau. Mihirau was an ancestress of the Te Kekerewai hapū and was a prominent woman of her time. The name Te Wai o Mihirau is referred to in the Ngāti Mutunga pepeha:
'Mai Te Wai o Mihirau (Mimi River) ki Te Wai o Kuranui (Urenui), koia tera ko te whakararunganui taniwha'.
Benson, M., McKay, A-M., Kanz, W., Shivnan, S., Ruru, I. (2022). Te Rūnanga o Ngāti Mutunga Mauri Compass Assessment of the Mimitangiatua and Haehanga River. Prepared by Te Rūnanga o Ngāti Mutunga. Urenui, Aotearoa New Zealand.


In 2020, Ian Ruru and his sons Riaki and Manawa helped us to apply the Mauri Compass tool and to undertake assessments of the Mimitangatua and Urenui awa, being two of our four tupuna awa (the others being the Onaero and Waitara). The project was sponsored by Te Wai Māori Trust.
Benson, M., McKay, A-M., Ruru, M., Ruru, R., Ruru, I. (2020). Te Rūnanga o Ngāti Mutunga Mauri Compass Assessment of the Urenui River and the Mimitangiatua River. Prepared for Te Wai Māori Trust by Te Rūnanga o Ngāti Mutunga. Urenui, New Zealand.
The Mauri Compass values and recognises the skills and knowledge that Ngāti Mutunga whānau have – ngā taonga tuku iho. We found that the tool used a good balance of mātauranga Māori and science data collection. We embraced the tool as a way to monitor effect of resource consents on the mauri of our awa, and to support our involvement in Resource Management Act processes.
Present findings of Mauri Compass assessment of the Mimitangiatua and Haehanga catchments
Express aspirations of Te Rūnanga o Ngāti Mutunga in Environment Court case against Remediation New Zealand
For the purpose of our involvement in the Environment Court hearing on the Remediation New Zealand consent applications (Environment Court Case ENV-2021-AKL-000059) we have used the Mauri Compass tool to evaluate the Haehanga catchment.
The outcomes of the Mauri Compass assessment were based on Ngāti Mutunga mātauranga articulated through hui and wānanga, and anchored with reference material including the Ngāti Mutunga Iwi Environmental Management Plan.
Three of the twelve Mauri Compass indicators focus on the health and well being of our freshwater sentinel taonga, the tuna. We visited four sites on the Mimitangiatua awa (for our 2020 Report) and four sites in the Haehanga stream (in 2022).
Poor water quality in the Mimitangiatua, linked to water pollution across the catchment, has resulted in an all-encompassing rāhui within lower parts of the catchment (including harvesting of fish, shellfish, and undertaking swimming and recreation).
Key findings from this updated Mauri Compass assessment are located in Table 3. In these findings we have compared the mauri of the Haehanga with the mauri of the Mimitangiatua. These two waterbodies are integrally linked. While the mauri of both the Mimitanguatia and Haehanga awa has steeply declined since European settlement, the Haehanga awa has fared the worst.
Complete chemical pollution
Total decline in species health
Complete loss of traditional practices
Near extinction of native species
With specific reference to the Haehanga awa and in comparison to pre-European times, all 12 Mauri Compass indicators have been profoundly impacted to the following extent:

The mana of the Haehanga has been severely trampled on, with that catchment subject to extensive physical alteration and discharge of pollution into surface and ground waters. This is an affront to Ngāti Mutunga.
It is apparent that the chemical pollutants (Chemhazards) emanating from the RNZ site set off a chain reaction impacting on Ngāti Mutunga taonga species, their health and abundance. This in turn prohibits our ability to nurture and practice mahinga kai thereby impacting on our spiritual and cultural obligations as kaitiaki of our tupuna awa.
This scale of transformation and impact on the mauri of the Haehanga awa is particularly abhorrent to Ngāti Mutunga. Ngāti Mutunga attribute the demise to the operation of the RNZ site.
WHIRIA TE TANGATA, WHIRIA TE KAUPAPA, WHIRIA NGĀ TAONGA TUKU IHO







Ko wai koe? Ko wai ahau? He puna koro puna ka heke mai, ka tuku ki a tukia e te poa ka kore e mimi tika koro puna ka koro puna ka koro puna

Ngāti Mutunga descends from a number of ancestors who lived in the area occupied today by ngā uri o ngā tūpuna o Ngāti Mutunga. These ancestors include Tokauri, Tokatea, Mihirau, Heruika, Pūrakino, Rakaupounamu, Uenuku (son of Ruawahia), Hineweo, Hinenō, Te Hihiotū, Kahukura, and Mutunga.
Ngāti Mutunga also descends from ancestors who arrived on the Tokomaru, Tahatuna and Ōkoki waka such as Taitaawaro, Manaia and Ngānganarūrū.
The traditional rohe of Ngāti Mutunga is indelibly etched into both physical and historical landscapes, spanning approximately 63,200 hectares.
Within these boundaries lie the Mimitangiatua, Urenui and Onaero catchments, with their mainstem and supporting river valleys providing important linkages.
Over generations, the descendants of these tūpuna intermarried and became generally known as Ngāti Mutunga.
The Papatiki stream signals the interface with Ngāti Tama in the North. From here, the stream flows past Titoki pa and then outlines the extremities of tūpuna mana as far north as the Mangahia Stream from which an easterly direction is struck to Huanui, then northeast to Waitara-iti. The rohe then finds a natural eastern definition in the Waitara River as the river flows southward to the Pouiatoa precinct.
From here, the border extends further south and then northwest along the Taramoukou stream to a point where the Waitara river connects with the Makara Stream. The confines of manawhenua are then traced in a northerly direction, skirting slightly west of the Poukekewa, Poutotara, and Pukemai streams. The Mangahewa Stream then provides an outline for the duration of the course to the coast.
Our three Tupuna awa, Onaero, Urenui and Mimitangiatua are prominent features of our whenua, culture, and everyday lives. Another name for Mimitangiatua is Te Wai o Mihirau. As mentioned previously, Mihirau is one of our very early and respected ancestors from whom many of our people descend.
Mai Te Wai o Mihirau (Mimi River) ki Te Wai o Kuranui (Urenui), koia tera ko te whakararunganui taniwha
The mainstems and supporting river valleys and catchments of our Tupuna awa also provide important linkages and resources in all directions across the rohe. The area of the Ngāti Mutunga rohe described above is approximately 63,200 hectares (156,000 acres).
Ngāti Mutunga iwi was an autonomous, independent and self-governing confederation of hapū including Te Kekerewai, Ngāti Hinetuhi, Ngāti Aurutu, and others.
These hapū exercised tino rangatiratanga over the traditional rohe, with distinct communities managing their territories.
In more recent times, Ngāti Mutunga has interacted as a single tribal grouping known today as Ngāti Mutunga.
Promoting an understanding of Ngāti Mutunga values & responsibilities in our rohe
Protecting the environment for future generations
Demonstrating Ngāti Mutungatanga through our role as kaitiaki

Figure 1: Mātauranga Māori, intergenerational transfer of knowledge.
Our IEMP is a mandated set of policies that codifies Ngāti Mutunga values to support and educate iwi members working on environmental issues. The IEMP has a legal effect under the RMA and should influence external agencies to work more closely and effectively with Ngāti Mutunga in environmental management within our rohe.
Continue to develop our capacity to engage in environmental issues
Encourage our rangatahi to take an interest in and pursue studies in relevant environmental fields
Look for opportunities to involve our people in environmental monitoring
Work with other iwi groups on issues of mutual interest

Figure 2: Our Iwi Environmental Management Plan. Ngāti Mutunga values become embedded in the planning documents and management practices of relevant agencies
Ngāti Mutunga is effectively involved in the management and protection of natural resources
Agencies responsible for environmental management understand and respect the role, value, and responsibilities of Ngāti Mutunga
Partnerships between Ngāti Mutunga and agencies responsible for environmental management are developed and enhanced
Agencies foster the capacity of Ngāti Mutunga to engage in environmental management, particularly decision-making processes and planning
Natural and physical resources are managed in a holistic and integrated way
The state of the natural environment is restored to a state which supports the values and customs of Ngāti Mutunga
The life-supporting capacity of the environment is protected and supported
Ngāti Mutunga is actively involved in the day-to-day management of the environment
Ngāti Mutunga capacity to engage on environmental issues and participate in activities such as environmental monitoring is enhanced
All plans, policies, strategies, regulations, laws and other methods of environmental regulation or planning identify and avoid negative effects on the health and wellbeing of the Ngāti Mutunga community
Establish a sense of belonging and kaitiakitanga amongst the whole community
The kaitiakitanga tradition of Ngāti Mutunga is continued through the generations
The traditions of Ngāti Mutunga describe the cultural, historical, and spiritual association of Ngāti Mutunga and the waterways in our rohe. For Ngāti Mutunga, these areas represent the links between our tūpuna and, present and future generations. This history and relationship reinforce tribal identity, connections between generations, and confirms the importance of freshwater to Ngāti Mutunga.
The Onaero, Urenui, Waitara, and Mimitangiatua awa are specifically described in the Ngāti Mutunga Iwi Environmental Management Plan, including reference to the resources provided, taonga, pā, kāinga, taupā (cultivations), and kōiwi along riverbanks. The role of rivers as transport waterways is noted.
Restoring the physical health of rivers and waterways
Re-establishing spiritual connections with our awa
Re-establishing the relationship between people and rivers
Ensuring access to waterways and educating others about their importance
Ngāti Mutunga used all parts of the Mimitangiatua catchment, as this was a key corridor from the coastal plain into the hinterland, with tracks along and across catchments, all the way to the Waitara and Whanganui awa. The rivers and streams were our highways and roads, providing travel up and down waterways both for collecting kai and engaging with whānau.
Mana whenua practised mahinga kai throughout, using the deep and wide waters and tauranga waka of the Mimitangiatua awa and its floodplains, and using the unique and varied resources and sustenance offered by its contributing catchments.
Water is descended from Papatūānuku and Ranginui; it is the lifeblood of the people because it sustains the growth of plants, animals, and people. Our children play and bathe in the rivers in our rohe, and many sites of significance are located along waterways. Water has spiritual qualities of mauri and wairua. These qualities are related to the physical wellbeing of the water and are damaged by overexploitation, pollution, or misuse of water.
Water is often seen as a commodity, but we see water as a taonga to be valued and respected. It is part of our whakapapa and our health – if the water is sick then so are we.
Our tūpuna had considerable knowledge of the ways in which to use the resources associated with water, and tikanga for the proper and sustainable use of these resources. We did not pollute our waters. It is our responsibility, as kaitiaki, to ensure that the values and tikanga, as well as the water itself, is restored, endures, and is passed on to future generations.
Awa (rivers) in the rohe were and still are central to the social, spiritual, and physical lifestyle of the Ngāti Mutunga people. Many pā are located along the rivers, testament to the occupation of the area by our tūpuna.
Ngāti Mutunga utilised the entire length of each awa for food gathering. The river mouths provided pipi, pūpū, pātiki, kahawai, and other fish. Tuna and piharau were found in the upper reaches.
Our tūpuna had considerable knowledge of whakapapa, traditional trails and tauranga waka, places for gathering kai and other taonga, and tikanga for proper resource utilisation.
The Onaero, Urenui, and Mimitangiatua have been occupied by the tūpuna of Ngāti Mutunga since before the arrival of the Tokomaru and Tahatuna waka. The Haehanga is a sub-catchment of the Mimitangiatua, located 14.5km from this river mouth, approximately 4km from the coastal plain.

Not widespread throughout the North Island, piharau are an important and personalised way for Ngāti Mutunga to practice manaakitanga.
Help ourselves and others understand the significance and value of the water within our rohe
Ensure that any use of water maintains the cultural and ecological values associated with water
Ensure waterways are healthy and support Ngāti Mutunga customary activities
Lack of Crown recognition of iwi ownership of rivers, leading to an inability of iwi to develop, use and protect water resources
Lack of Ngāti Mutunga participation in freshwater management
Lack of recognition of the special significance of particular waterways to Ngāti Mutunga
Lack of protection of the mauri and wairua of waterways
Lack of monitoring of and information on the health of waterways in our rohe
Lack of restoration of the health and productivity of waterways
Lack of knowledge about whether current and future uses of water are sustainable
Lack of protection of wāhi tapu and wāhi taonga associated with waterways
Our people have seen great changes in our rivers over the years. Our tūpuna were sustained by the rivers; they provided many resources, especially food. They were also key transport routes.
The changes to these rivers have degraded their mauri and wairua, and we now find that they cannot sustain us. In addition, many of the traditional practices associated with our rivers are no longer able to be practiced. Many of our kai species have disappeared, and the physical appearance of the rivers has changed beyond recognition.
Restore the physical and spiritual health of the rivers
Re-establish the relationship between the people and the rivers
Educate others in the community about the importance of the rivers in our rohe
This 'Mauri Compass Project', is another example of how we are working towards these objectives.

Tiki Ngārangi demonstrating that the rangatahi of today will be the rangatira of tomorrow.

Figure 4: The Mimitangiatua River.
The full name of the Mimi River is Mimitangiatua. The river is also known as Te Wai o Mihirau. Mihirau was an ancestress of the Te Kekerewai hapū and was a prominent woman of her time. The name Te Wai o Mihirau is referred to in a Ngāti Mutunga pepeha:
There are many pā and kāinga located along the banks of the Mimi River. These include Mimi-Papahutiwai, Omihi, Arapawanui, Pukekohe, Toki-kinikini, and Tupari.
There were also a number of taupā (cultivations) along the banks of the river, supporting the communities that lived there.
Arapawanui was the pā of Mutunga's famous grandsons Tukutahi and Rehetaia. They were both celebrated warriors, especially Rehetaia.
The Mimitangiatua River and associated hūhi (swampy valleys), ngahere (large swamps), and repo (muddy swamps) were used by Ngāti Mutunga to preserve taonga. The practice of keeping wooden taonga in swamps was a general practice of the Ngāti Mutunga people for safekeeping in times of war.
To the people of Ngāti Mutunga, all the rivers and their respective valleys are of the utmost importance because of their physical, spiritual, and social significance in the past, present, and future.
Ngāti Mutunga sees the welfare of the people and the welfare of the water as interlinked.
"Without healthy water you won't have a healthy rohe. And without a healthy rohe you can't have healthy people" – Jamie Tuuta, Chairman, Te Rūnanga o Ngāti Mutunga.
The Haehanga is a part of the Mimitangiatua. It is one of the large sub catchments after leaving the coastal plain on the way up the Mimitangiatua. This awa would have offered valuable resources and respite to mana whenua travelling up and down the Mimitangiatua, and whānau harvesting mahinga kai.
This would have been particularly so where the Haehanga joins the Mimitangiatua, and likely quite a way upstream in the Haehanga. The confluence of the Haehanga and Mimitanguatua was a pā tuna (Sam MacDonald, pers. comm).
The Haehanga valley was particularly close to Pukekahu Pā and would have been a key mahinga kai area for those whānau.
The Haehanga was also on the way downstream when travelling to the Mimitangiatua estuary, a key mahinga kai area for us.
Waka would have travelled up and down the Mimitangiatua, within the estuary and coastal plain, and beyond, along its gently meandering lowland path.

Figure 3: Recorded tracks in the vicinity of the Haehanga.
The Haehanga historically had extensive wetlands and a network of healthy smaller waterways and floodplains that would have offered a wide range of resources for mana whenua. Wetlands and floodplains offer a wide variety of resources for tangata whenua, from fruiting riparian tree species to materials associated with flax and raupo, to kōura that inhabit and thrive in smaller upland streams and an abundance of birdlife.
In my opinion, having viewed historic aerial imagery the Haehanga Stream would once have provided habitat (in the form of connected wetlands, floodplain, and forested headwaters) for giant kōkopu, banded kōkopu, īnanga, smelt (in the lower reaches), redfin, common and Cran's bullies and abundant tuna (of both species), with kōura and kākahi also likely abundant.
Evidence in chief to Environment Court of Kathryn McArthur, dated 14 April 2022.
While there are no records of pā and kāinga along the banks of the Haehanga, its strategic location and abundance of resources would have made this catchment valuable to mana whenua.

Figure 4: Pukekahu Pā location and tracks.

Mahi Tamariki and Te Aroha – Urenui Pa c1920
Kia ū koe ki tō marae, mā tō marae ka kiia koe he tangata
Hold fast to your marae, for it is your marae that makes you a whole person.

Figure 5: Historic tracks and travel routes along the Uruti and Mimitangiatua awa.
This collage shows the degradation of values over time in the Haehanga catchment.



Figure 6: Haehanga aerial photo collage (1943, 1982, present day).
The catchment was still largely natural, with meandering waterways including associated wetlands and floodplains. Some areas of ngahere had already been changed into pasture for livestock.
While the extent of pasture had increased, the majority of waterways remained within their natural alignments, with associated natural wetlands and floodplains.
Large scale changes have taken place since Remediation NZ and its predecessor started operating in this river valley. The taiao has been severely impacted.
Here is a map of the Remediation NZ site at Uruti.

Figure 7: Remediation NZ Uruti Site Map.
The Remediation New Zealand facility represents a significant industrial operation within the Haehanga catchment. The site processes various waste materials including:
Composting operations handling various organic materials and byproducts
Processing of drilling wastes, sawdust, and other industrial materials
Handling of materials that pose environmental and cultural risks to the waterway
The operation of this facility has had profound impacts on the mauri of the Haehanga awa, as documented through our Mauri Compass assessment. The facility's activities have created both point source and diffuse pollution that affects water quality, aquatic life, and the cultural values that Ngāti Mutunga hold for this waterway.
The founding principles of the Mauri Compass are based on this whakataukī:

The Mauri Compass was designed to assess the mauri of any waterway and was refined over a significant period of time with the input of Tairāwhiti mātauranga Māori and science experts including:
Turanganui a Kiwa Water Quality Enhancement Group (KIWA)
Wastewater Technical Advisory Group
Iwi leadership and guidance
Staff at the Gisborne District Council
The Mauri Compass dashboard is designed around the 12 indicators [attributes] that inform the mauri of a particular waterbody. It is also designed to visualise the complex interrelationships in a straightforward manner.
Each of the twelve indicators are outlined next.
In our 2020 Mauri Compass Report for the Urenui and Mimitangatua rivers, we were also trained up as accredited Mauri Compass assessors so that we can continue to monitor our mauri restoration projects.

Figure 8: Mauri Compass 'ringa raupā' from the 2020 assessment.

Figure 9: Marlene Benson & Barry Matuku demonstrating eDNA-testing at Uruti School.
Taranaki Regional Council staff enthusiastically attended the Mauri Compass training that we hosted in 2021. It was an excellent opportunity to bring together western science and Ngāti Mutunga mātauranga.


Figure 10: Taranaki Regional Council Mauri Compass training.
The training provided an opportunity to share mātauranga Māori with council staff and demonstrate the practical application of the Mauri Compass tool.
These sessions helped build understanding and working relationships between Ngāti Mutunga and regional authorities.
The collaboration demonstrated how traditional knowledge and western science can work together effectively in environmental monitoring.
This collaborative approach has been essential in building credibility for the Mauri Compass methodology and ensuring that our cultural values are recognised in formal environmental assessment processes.
Ngāti Mutunga has been doing freshwater surveying for approximately four years now and we have trialled a couple of different cultural monitoring tools.
For us, the Mauri Compass had a good balance of mātauranga Māori and science data collection. This will make it easier to be recognised by Taranaki Regional Council and the New Plymouth District Council while still putting Ngāti Mutunga cultural values and concerns first.
Using tuna as a major taonga species built on the knowledge that Ngāti Mutunga whānau have about the customary uses, gathering and protection of a taonga species.
The survey values and recognises the skills and knowledge that Ngāti Mutunga whānau have – Ngā taonga tuku iho.
The Mauri Compass method involved Ngāti Mutunga whānau aged from 2 to 70 plus and it will be easy to involve the whole Ngāti Mutunga whānau during any future surveying.
The purpose was to use the Mauri Compass tool to assess the mauri of the Mimitangiatua and Haehanga rivers utilising mātauranga Māori and the practice of mahinga kai at eight key sites, four on the Mimitangiatua and four on the Haehanga.
This will increase everyone's skills in the collection of scientific data while recognising and affirming the cultural knowledge and expertise and experience of Ngāti Mutunga whānau participating in this work. It also helps to reconnect us and/or strengthen our relationships as tangata whenua to our whenua, our awa and ngā mātua tupuna.
Through wānanga, we began by answering a set of questions and calculating scores based on our knowledge of our tupuna awa. We calculated scores for the historic or pre-European state and for the current state for the Mimitangiatua and Haehanga. Each set of questions feed into the twelve indicators that form the Mauri Compass.
Wolfgang Kanz and Ian Ruru joined us for an initial site visit with RNZ representatives on December 9th, 2021. The method, data, equipment, and skills required were discussed in depth and a survey plan was confirmed. We also identified four Mauri Compass testing sites for the Haehanga catchment.

The bottom end of the Haehanga Catchment, close to the Mimitangiatua
Near the top of the catchment, as permitted by water depth at that time of year
Adjacent to the Remediation NZ operation, in close proximity to ponds
At the downstream end of the bulk of the Remediation NZ operation
The four Haehanga sites were selected to enable a holistic assessment of the catchment.


Figure 12: Haehanga catchment testing site images.
The raw scores from our wānanga were entered into a Microsoft Excel spreadsheet with algorithms and used to generate bar charts and dashboards. The bar charts and dashboards provided excellent visual reminders of the mahi that we have to do to restore the mauri of our tupuna awa. We also cross-referenced and ground-truthed our scores with local reference material.

Figure 9: Uruti School
A drone video was produced in 2020 to highlight our rohe and mahi, our 'ringa raupā' in action and on location. We had a very enjoyable time.
Mahinga kai is about mahi ngā kai – the way we gather resources, where we get them from, how we process them, and what we produce. These places, processes, and skills are an essential element of Ngāti Mutungatanga. Our tūpuna were able to feed, clothe, and house themselves using the resources provided by Papatūānuku.

European settlement completely disrupted traditional mahinga kai cycles by destroying habitat (for example, by clearing forests and draining wetlands) and introducing species which eat or outcompete native species (for example, possums, cats, trout). The confiscation of land also separated Ngāti Mutunga from our traditional resources, leaving us unable to live from the land as our tūpuna did.
Waterways were once an important source of mahinga kai, providing diverse food sources for our people
As the years passed we have seen a marked decrease in the availability of mahinga kai
Some of our customary food sources are not available at all, while other species, once plentiful, have become scarce
Our ability to undertake cultural customs and practices has been eroded through limited or no access to our tūpuna awa
Furthermore, water quality has made it unsafe for contact, both in terms of Western science health risks and cultural objections to the contaminants in the water.
Ngāti Mutunga understands the importance of protecting and preserving these species and our awa, our customs and practices, and we should be able to practice mahinga kai sustainably and safely within our rohe according to our tikanga.
To retain our traditions around mahinga kai, and pass those traditions on to future generations
To improve the health of our waterways to a state where they can support mahinga kai

Rawiri McClutchie, Riaki Ruru, Ann Maree McKay, Te Araroa McKay demonstrating textbook net-setting techniques (2020).
All nets were unbaited, set perpendicular to the stream, and retrieved the next morning. The image also lists the cultural and environmental parameters that are recorded.
To that end we:
The following table lists aquatic mahinga kai species that were considered in our assessment, comparing historical presence with current status in both the Mimitangiatua and Haehanga waterways.
The Mauri Compass was used to compare the following states:
Pre-European versus current state assessment
Pre-European versus current state assessment
The outcomes of the Mauri Compass work were derived from Ngāti Mutunga mātauranga Māori articulated through hui and wānanga and anchored with reference material such as the Ngāti Mutunga Iwi Environmental Management Plan.
It also enabled our iwi members to upskill themselves in the long-term monitoring of our tupuna awa.

Figure 14: Map of Mimitangiatua (2020) and Haehanga (2022) sites.
This map shows the locations of our assessment sites across both waterways, enabling direct comparison of conditions and trends. The strategic placement of monitoring sites allows us to understand the full impact of various activities on the mauri of these important awa.
The comparative approach allows us to understand the relative impacts on different parts of our rohe and identify priority areas for restoration.
These baseline assessments provide the foundation for ongoing monitoring of restoration efforts and environmental changes.
The process successfully integrated traditional knowledge with scientific methodology to create a holistic assessment framework.
This section presents the Mauri Compass Results, and an in-depth Discussion as to how the indicator scores were derived. It is arranged as follows:
Comparison of Mimitangiatua and Haehanga indicators with detailed comments
Visual comparison of indicators between the two waterways
Mauri Compass Dashboard comparisons showing complex interrelationships
Detailed analysis of each of the 12 indicators with comparative insights



The comprehensive results reveal the severe impact on the mauri of both waterways, with the Haehanga showing particularly concerning declines across all indicators.
The following table provides a comprehensive comparison of all 12 Mauri Compass indicators between the Mimitangiatua and Haehanga waterways, showing the dramatic decline from pre-European times to current conditions.
It is apparent that the chemical pollutants (Chemhazards) emanating from the RNZ site set off a chain reaction impacting on Ngāti Mutunga taonga species, their health and abundance. This in turn prohibits our ability to nurture and practice mahinga kai thereby impacting on our spiritual and cultural obligations as kaitiaki of our tupuna awa.

Figure 15: Bar Chart comparing Mimitangiatua and Haehanga indicators.

The Haehanga scored significantly lower than the Mimitangiatua across most indicators, demonstrating the severe impact of the RNZ operations.
While Ngāti Mutunga are holding on to their mātauranga and strive to undertake their customs and practices across their rohe, this is not possible across large parts of their rohe.
The Haehanga has been both inaccessible and is culturally unavailable as a resource because of the tapu imparted on the awa by Remediation NZ.
Order of magnitude increase in faecal indicators between upper Haehanga and below RNZ site
Chemical hazards score showing complete contamination from RNZ operations
Flow time from Haehanga to Mimitangiatua Estuary - insufficient for pathogen die-off
Biohazards are significantly worse in the Haehanga. Faecal microbes and pathogens are introduced to the Haehanga Stream from the waste brought onto the Remediation NZ site, including animal, bird and fish offal, skins, manures, and paunch waste.
Chemical Hazards are significant in the Haehanga Stream because of diffuse and point discharges of waste from Remediation NZ. Concentrations of contaminants in the Mimitangiatua downstream of the Haehanga confluence are elevated for some contaminants.


The dashboards play a key role and are designed to visualise the complex inter-relationships between indicators in a straightforward manner.
Chemical pollution from RNZ operations creates the foundation for all other impacts
Biological contamination compounds the chemical impacts, making water unsafe
Poor water quality directly impacts the health and survival of taonga species
Unhealthy conditions lead to dramatic reductions in taonga species numbers
Without healthy, abundant species, traditional food gathering becomes impossible
Inability to practice mahinga kai affects Ngāti Mutunga's role as kaitiaki
For the Haehanga awa, the detrimental impact of Chemhazards and Biohazards on Taonga Health and Taonga Abundance creates a cascading effect
The lack of Taonga Abundance directly affects the abundance of Mahinga Kai species, breaking cultural connections
The inability to practice Mahinga Kai traditions directly affects the ability of Ngāti Mutunga to exercise their role as kaitiaki
The visual representation clearly shows how environmental degradation in the Haehanga has created a web of interconnected impacts that extend far beyond simple water quality measures to affect the very essence of Ngāti Mutunga cultural identity and responsibilities.
The outcomes of the Mimitangiatua and Haehanga Mauri Compass Assessments provide detailed insights into the specific impacts on each indicator. This analysis compares the current state of both waterways and explains the reasoning behind each assessment.
After discussion, Ngāti Mutunga whānau recognised that people had a stronger connection to the Urenui than the Mimitangiatua, mainly due to ease of access to Urenui – especially the river mouth and estuary.
Connection affected by lack of access (pre-RNZ) and concerns about RNZ activities negatively impacting the health of the Haehanga and mahinga kai within the site.
Large complicated site operating under 4 different companies, over 21 years with inadequate information about site activities/standards/goods received
Low standard of management and inadequate resourcing observed during early site visits
Type of goods received have high risk of contamination - drilling waste, treated sawdust, contaminated soil
Volume of material and leachate has led to excessive nitrogen loading of irrigation areas
Treated sawdust was on site for approximately 15 years before being identified as major contamination source
Most Ngāti Mutunga whānau reported concerns with changes they observed downstream from the Haehanga in the main stream of the Mimitangiatua, including concerns that water was no longer safe to drink and monitoring reports stating water was not suitable for stock and never safe for immersive contact.
This report has amended the original Mauri Compass assessment of the Mimitangiatua and Urenui awa, for the purpose of providing evidence to the Environment Court Case ENV-2021-AKL-000059 Remediation NZ Ltd v Taranaki Regional Council. The Haehanga Catchment has been added and Urenui Catchment removed. The report therefore integrates information relevant to the Haehanga, and reports on changes in mauri specific to that catchment.
The proposal by Remediation NZ cannot guarantee that discharges of pollution will cease, and the poor compliance track record validates this concern.
The effects will continue in perpetuity unless the site is remediated, and the mana is returned to the awa.
Only through comprehensive remediation can the mauri of the Haehanga be restored for future generations.
A key reason for the failure of regional plans to protect freshwater is that hard science is seen to be the only legitimate way to articulate impact. Attempts to articulate the impact of water management on human well-being are constantly marginalised by the promotion of hard scientific knowledge regarding assessments. People's connections to particular places and environments are overlooked.
(Hammond, 2018, p. 26)
That in the long term the Haehanga is returned to the state it was pre-European – in the shorter term it is returned to the state it was pre the composting site now owned by Remediation New Zealand being there.
Taonga species richness and health is restored to sustainable levels
Water is safe to drink and the awa is suitable for cultural purposes and bathing
Riparian margins contain diverse plant, bird, and insect life with pest numbers at target levels
Soil adjoining the awa is safe to grow, harvest and eat kumara from
Continuation of native forest restoration in the catchment as per present planting programme
The Mauri Compass assessment has provided a comprehensive framework for understanding the current state of these important waterways and charting a path toward restoration. Through continued monitoring and collaborative effort, we can work toward restoring the mauri of the Haehanga and protecting the cultural and environmental values that are central to Ngāti Mutunga identity.
WHIRIA TE TANGATA, WHIRIA TE KAUPAPA, WHIRIA NGĀ TAONGA TUKU IHO
Weave the people, weave the purpose, weave the treasures handed down
Mauri Compass Assessment of the Mimitangiatua & Haehanga Awa