Waipā District Council searches for funding and solutions to fix Lake Te Koo Utu

Wednesday, 6 May 2020

Lake Te Koo Utu has been the recipient of stormwater runoff from nearby homes and roads for 50 years, contributing to its poor water quality.

The contaminated water of a popular Waikato lake remains a stumbling block for efforts to firm up a concept plan for its long term future.

Restoration and development projects proposed for Lake Te Koo Utu in Cambridge, worth nearly $1 million, are about to head out for public feedback as part of a draft concept plan under the Waipā District Council.

Improving the lake’s water quality is paramount but the council has been unable to find or fund a solution after decades grappling with the problem.

There had been a host of reports and options such as wetlands to filters, desludging, pumping extra water through the lake and “nanobubble” technology.

A pioneering study into stormwater management for Cambridge may help find solutions to treat runoff before the water arrives into the lake.

* Water restrictions lifted across Hamilton, Waipā and Waikato

A concept plan proposes a range of restoration and development projects for the lake and the Waipā District Council is looking for public feedback.

* Plans to save Lake Te Kō Utu to be open for official public discussion next year

Monthly monitoring by Waikato Regional Council, which only started in 2019, revealed the lake had elevated levels of nitrogen when measured against regional and international guidelines.

The lowest phosphorus result was three times higher than the regional council’s “unsatisfactory limit”.

There were also elevated levels of suspended solids, electrical conductivity and turbidity, or cloudiness, in the water.

Those details and more were presented to the council’s strategic planning and policy committee, when it met to review the concept plan for the lake.

The committee heard there were steps the council could take to reduce contaminants but the critical factor was treatment of stormwater before it was fed into the lake.

That work was “outside the scope of the concept plan” but a business case for a “pioneering study” into managing stormwater was proposed by the council’s water assets team.

What the concept plan proposes, is a wetland area to help remedy water quality issues, a boardwalk across the water with educational signage, restorative planting, a playground and upgraded walkways and entrances to the reserve.

Research by consultants Boffa Miskell and Te Miro Water showed elevated nutrients and contaminants in the lake were likely the result of stormwater from homes and roads for 50 years or more.

The problem would have started when roads were sealed, a kerb and channel network installed to manage water runoff, which was piped into the lake.

Previously, gravel roads would have drained into nearby grass berms.

The research said a major stormwater management system, beyond the boundaries of the lake, was needed to improve water, which eventually fed into the Waikato River.

Cambridge ward councillor Grahame Webber said he did not think the concept plan 'added a heck of a lot' to previous plans to address the water problems.

'But what I want to do is to get buy-in from iwi, the Waikato River Authority and regional council, so we can all go forward and get a heap of ideas and funding to help.'

Mayor Jim Mylchreest agreed and said the lake’s water quality had been a regular talking point for more than 30 years.

But solutions proposed had always “fallen over” because of costs.

“The feeling I get is that there is a willingness for the community to pay for the upgrade of this lake.

'I support the recommendations from Grahame, let's get on and do something rather than filing another report to the dungeons of council.'

The committee agreed to apply for funding from the Waikato River Authority and other agencies for the final lake concept plan, so the 'burden of the costs' does not fall on Waipā ratepayers alone.

The lake's restoration and development projects, worth $980,000, have been submitted to the Government's shovel-ready infrastructure fund.

Consultation on the lake concept plan opens May 18 to July 13.

Concept plan aspirations

* Improve water quality and habitat, improve water quality flowing into Te Awa o Waikato.

* Acknowledge the lake's historical and cultural significance.

* Enhance biodiversity.

* Improve and increase play and recreation opportunities.

* Strengthen connections between the lake and community.

Lake Te Koo Utu

* The lake reserve is about 20ha in the heart of Cambridge.

* It has historical and memorial features, a walking trail around the lake, picnic areas, a lookout, four clubs and fitness equipment on its upper terrace.

* The lake has a long association with Ngāti Koroki Kahukura and Ngāti Hauā

* Its restoration is ranked as a community priority.