Roto-Nui-a-Whatu  Lake Tuakitoto
Roto-Nui-a-Whatu Lake Tuakitoto


In 2017, in response to concerns about water quality, our staff began to work with the local community to scope restoration works for Lake Tuakitoto.

Water quality was found to be degrading with elevated levels of chlorophyll a, nitrates and phosphates found within the Lake, and the wider catchment had elevated levels of nitrate-nitrate, nitrogen and E.coli.

With the establishment of the Environmental Implementation Team in 2021, together with mana whenua, stakeholders, and the community we agreed on three key goals: an ecological assessment of the lake, introduce a water quality testing programme, and a hydrological assessment of the catchment.

About Roto-Nui-a-Whatu / Lake Tuakitoto

The Lake Tuakitoto wetland Complex is considered a Regionally Significant Wetland. Roto-nui-a-Whatu / Lake Tuakitoto is a remnant of a very much larger wetland system which included Lake Kaitangata. Lovells Creek is the main inflow to the lake, and there are many other small streams in the catchment. It is highly valued by Kāi Tahu for cultural and spiritual beliefs, values and uses, including mahika kai / traditional food gathering area, and wāhi taoka.

It performs a valuable hydrological function, serving as a natural flood ponding area and an integral part of the Lower Clutha Flood Control and Drainage Scheme. It is the only major wetland remaining in the Lower Clutha catchment.

It is also described as number five in New Zealand’s Top 10 Wetland Wildlife Habitats and supports a range of nationally and internationally rare or threatened species, including about 50 bird species, and threatened galaxiid populations.

The project and consultation process

ORC has dedicated $260,000 over three years (2021-2024) to enhance the Lake Tuakitoto catchment through community action to contribute to a healthy ecosystem for all to enjoy.

In 2018, two workshops were held with the community which identified community goals and values for the Lake Tuakitoto catchment, and it identified potential projects for the catchment.

In 2022, a meeting with mana whenua and key stakeholders for the Lake Tuakitoto catchment was held to discuss a draft outline management plan and feedback was provided. Due to COVID-19, an online consultation process was undertaken with the community to vote on the highest priority actions to be implemented for the catchment.

The three priority actions that were identified by the community, mana whenua and key stakeholders were:

  1. Ecological Assessment: Investigate the key stressors in the lake and catchment. What actions do we need to undertake to make the catchment more resilient?
  2. Water Quality Data: Introduce a water testing programme to assist with identifying sources of poor water quality.
  3. Hydrological Assessment: Investigate the impacts of flooding within the catchment and carry out further research to ensure that the current lake levels are sufficient to support environmental enhancement, flood protection and recreation.

The three priority actions, along with the collective vision and values for Roto-Nui-a-Whatu / Lake Tuakitoto, were compiled in the Lake Tuakitoto Outline Management Plan. This outline management plan was then approved by council for delivery.

Progress so far on the three priority actions

Ecological Assessment

ORC contracted Cawthron Institute to undertake an Ecological Assessment of Lake Tuakitoto. The aim of the ecological assessment was to identify drivers for the current ecological status of the lake and to identify possible actions that the ORC, in collaboration with the community, mana whenua, and key stakeholders, could undertake to make the catchment more resilient. The ecological assessment consisted of an analysis of historical data, and a fieldwork component. The final report on the ecological assessment was submitted to ORC on 31 July 2023, which was then shared to mana whenua, community representatives, and key stakeholders.

Water Quality Data

In June 2023, ORC added two more water quality monitoring sites to the Lake Tuakitoto catchment. This brings the total number of monitoring sites in the catchment up to three, with the existing site being Lovells Creek and the two additional sites targeting Stony Creek and Frasers Stream. Together, these three streams form the inflow into Lake Tuakitoto. These sites will be sampled monthly, and the data gathered will provide us with up-to-date information on water quality entering the lake complex. This monitoring programme will continue for the next two years (2022-2024).

Hydrological Assessment

This is the last of the three priority tasks that will be undertaken.


What else is happening?

ORC is investigating delivering a wastewater education programme in the Lake Tuakitoto catchment.

The aim of this project is to raise awareness around Onsite Wastewater Management Systems and how, when they are not maintained appropriately, they can impact water quality in the Lake Tuakitoto catchment. 


Next steps

Now that we have received the report on the ecological assessment of Lake Tuakitoto, ORC has begun drafting a plan for implementation of some of the recommended actions.


Page last updated 8 July 2024.