Cambridge Wastewater Treatment Plant

The project aimed to achieve shared ownership of decisions, recognise kaitiakitanga (guardianship) principles, give effect to Te Tiriti o Waitangi (the Treaty of Waitangi) and implement co-management processes to support the best-for-river outcomes under Te Ture Whaimana o Te Awa o Waikato (the vision and strategy for the Waikato River). 

Waipā District Council (Waipā DC) needed to redesign and reconsent the Cambridge WWTP to meet the needs of its 20,000 residents in Cambridge, with an anticipated growth to 50,000 residents by 2060. Waipā DC not only needed to allow for projected population growth, but it also needed to support the environmental outcomes aligned with the principles of Te Tiriti o Waitangi (the Treaty of Waitangi) and co-management objectives related to the Waikato River – which was to be the main discharge point.

Significant discharges, particularly those originating from wastewater treatment plants (WWTPs), pose the risk of causing heightened disputes, complicating the process of obtaining consent. Therefore, it was important to establish authentic partnerships with mana whenua, engaging closely with key stakeholders and communities to define a viable solution.

Part of the long-term solution for the Cambridge WWTP was to establish an effective partnership with local iwi, not only to support the decision-making process, but to enable the success of the project and deliver ‘best for river’ outcomes. Waipā DC formed the Kaitiaki Group, made up of key stakeholders including Ngāti Koroki Kahukura and Ngāti Hauā (mana whenua), Waikato Tainui (iwi) and the Waikato Regional Council, which provided a platform for deliberation, where key decisions could be workshopped, and environmental assessments, drawing from both western science and Mātauranga Māori, reviewed. 

A high level of commitment from staff and mana whenua representatives was important from the project's inception, fostering a collaborative environment centered on a clear vision for success. This paved the way for the adoption of a Mātauranga Matariki framework, serving as the foundation for all decision-making processes throughout the project's lifecycle. Under this framework, options were co-developed with the Kaitiaki Group, addressing various elements such as discharge quality enhancements and the identification of optimal locations for treated wastewater discharge. The framework, symbolised by Matariki and segmented into nine Atua domains, provided a lens through which environmental themes were addressed, and mana whenua issues and solutions were organised.

This co-development process extended to the assessment and consideration of key components and phases of the WWTP project, supporting the cultural treatment of wastewater and the acknowledgment of the site's rich cultural history were integral to the design and construction phases. Tangible outcomes, such as the placement of carved stones, Pou and significant tree plantings, alongside processes like site blessings and cultural inductions, highlighted the project's commitment to cultural sensitivity and respect.

This partnership approach facilitated key decisions through collaborative discourse, with over 20 hui and several site visits undertaken since 2020. The process has not only enhanced social and environmental outcomes but has also fostered community engagement while infusing a cultural lens through the Mātauranga Matariki framework.

The project unfolded in two stages:

• Stage 1: Obtaining a short-term resource consent which enabled us to address immediate compliance issues thorough investigation, engagement and design of the long-term solution. Working closely with Waipā DC and the Kaitiaki Group, we led environmental investigations, consenting processes and short-term upgrades to the WWTP.

• Stage 2: Simultaneously, we collaborated with Waipā DC and the Kaitiaki Group to develop the long-term wastewater treatment vision for Cambridge. Over several years, we managed the project, conducted technical assessments and co-designed consent conditions with mana whenua, achieving shared ownership and recognition of kaitiakitanga principles. 

The impact of the Cambridge WWTP project extends well beyond infrastructure development, involving environmental, cultural, social and long-term sustainability considerations. Through authentic partnerships and collaborative decision-making, the project successfully achieved shared ownership of outcomes and has created a legacy of environmental care and cultural respect.