Lake Te Koo Utu, once a place of peace and pride in the heart of Cambridge, is now in quiet crisis. Its waters continue to decline – clouded not just by sediment, but by a growing sense of loss. Mary Anne Gill reports.
Lake Te Koo Utu
Lake Te Koo Utu, a cherished sanctuary in the heart of Cambridge, is facing a grim future.
Despite efforts to improve its water quality, new data confirms the lake’s condition is worsening – prompting calls for stronger community collaboration and urgent action.
Rain gardens installed by Waipā District Council three years ago to filter stormwater runoff from nearby roads have made little to no difference to the lake’s water quality.
As the lake’s health worsens, voices from across the community are calling for unity, care, and urgent action to save a taonga slipping away.
Dale-Maree Morgan
Waipā Māori ward councillor Dale-Maree Morgan says it’s time for Māori and Pākehā to work more closely together. She recently connected the Cambridge Tree Trust with Ngāti Hauā Iwi Trust’s Taiporutu Hauraki, inspired by hearing Trust chair Peter Fisher speak at recent Long Term Plan hearings.
“Knowing what it’s like at Lake Te Koo Utu, it really needs some attention,” she said.
Waikato Regional Council lake scientist Mat Allan says the upcoming Land Air Water Aotearoa report on the 4.6ha lake is unlikely to show any improvement. The lake’s Trophic Level Index (TLI) – which measures chlorophyll, nitrogen, phosphorus, and water clarity – was 6.9 in 2023, up from 6.7 in 2022 and 6.2 in 2021. A higher TLI score indicates poorer water quality.
For comparison, Hamilton’s Lake Rotoroa had a TLI of 4.4 in 2023, while Lake Ngā Roto’s was 6.1, down from 6.7 the year before.
Before …. an uninterrupted view looking west towards St Andrew’s Anglican Church across Lake Te Koo Utu.
After ….. the same view seven years later with bamboo having taken over the bank. Photos: Mary Anne Gill
Allan attributes the worsening condition to Cambridge’s growing population and traffic, which is responsible for an increase in runoff containing sediments, heavy metals, and hydrocarbons.
“Looking at the data, we’re not seeing any improvement,” he said. “If the lake doesn’t show signs of recovery, we many need to consider different strategies.”
Despite the grim outlook, Allan remains hopeful.
“I still think there’s hope for the lake. There’s a lot of research underway exploring innovative restoration methods.”
That research is being led by Earth Sciences New Zealand – a merger of NIWA and GNS Science.
Lake Te Koo Utu drains east into the Karāpiro Stream and eventually the Waikato River. Earlier this year, 200 dead non-native goldfish were removed from the lake after heavy rain followed a prolonged dry summer. A public warning was issued to keep dogs away from the water.
Te Koo Utu is one of Waikato’s 14 riverine lakes, formed when alluvial deposits diverted the original path of the Waikato River. At just 2.4 metres deep, the lake spans 4.6 hectares within a 20-hectare reserve in the heart of Cambridge.
Since human settlement, clearance of the original forest and wetland vegetation and the switch to agricultural land use has substantially changed the condition of the region’s riverine lakes. Many are now turbid (cloudy) and can’t support submerged plants.
Lake Te Koo Utu holds deep spiritual, cultural, and historical significance for mana whenua. Ngāti Korokī Kahukura and Ngāti Hauā have long associations with the lake, which was referred to as the oko horoi (wash bowl) by King Tāwhiao.
Lake Te Koo Utu 1954. Photo: Whites Aviation
Lake Te Koo Utu 1975. Photo: Whites Aviation
While lake restoration is part of Waipā’s Long Term Plan, progress depends on asset sales – and the council’s current financial constraints have pushed the project down the priority list.
Morgan sees her role as a Māori ward councillor as one of connection. The recent meeting she facilitated between Ngāti Hauā, the Tree Trust, and National Wetlands Trust chair Don Scarlet was a step in that direction.
Don Scarlet
“They talked for ages… the magic and the pearl drops that just dropped out of those three meeting.”
But the terrain around the lake presents challenges. The Tree Trust, with its ageing membership, can no longer manage the weeding as it once did. A long-term weed control programme is needed to tackle invasive species like bamboo and tradescantia, which threaten native regeneration and block key view shafts, the trust said in its submission to the Long Term Plan.
Otherwise, the deterioration over the past 10-15 years will continue and cause further embarrassment to the town, said Fisher.
“Committing to and executing a plan to manage invasive weeds taking over parts of the southern embankment of Lake Te Koo Utu and replanting with suitable trees will restore this stunning location and be a source of pride for Cambridge into the future.”
Judith Browne, another submitter on the lake, is saddened by the state of Te Koo Utu.
“Council cannot afford to turn its back on the bamboo. I consider it to be the most serious problem on the banks of the lake. Use the community to provide labour if possible. Follow up needs to be on going,” she said.
Agapanthus have spread around Lake Te Koo Utu. Photo: Mary Anne Gill
She also called for the removal of all agapanthus from the lake boundaries. They were planted nine years ago, never deadheaded and have been left to spread.
“It is very foolish to plant any species that has a tendency to spread.
“In its place, for example, plant astelias, ferns, hebes, corokias, coprosmas – even azaleas or hydrangeas,” she said.
“Lake Te Koo Utu is a much-loved area in Cambridge. It is a place of peace and beauty if you don’t look at the problems. The lake could become a taonga that Cambridge can be proud of.
“Imagine if the weeds were removed and the banks were flourishing with pockets of rimu, punga, maples, redwoods to name a few of the beautiful trees which are already there. It could be so beautiful,” said Browne.
Lake Te Koo Utu 2018
