Cost to clean lake ‘prohibitive’
The water quality problems which surfaced on Cambridge’s Lake Te Ko¯ Utu over summer look set to remain unresolved.
Stagnant water was blamed for dead fish and ducks appearing around the lake in February, sparking debate on what could be done to fix the problem at a recent Cambridge Community Board meeting.
People heard there was no easy fix. It was too costly to install an aerator, the Waikato Regional Council would not allow the lake to be dredged and a plan to flush surface water through the lake from a nearby development, to improve flow, had fallen over.
It was made clear by community board chairman Mike Pettit, Waipa mayor Jim Mylchreest and councillor Grahame Webber that the cost of cleansing the lake would currently be ‘‘prohibitive’’.
Cambridge resident Brian Dunstan, at the meeting, said the water quality of the lake had become a potential health hazard over the summer, reminding people of the many ducks and fish which had become ill or died.
In July 2016, at an open day at the Lakewood Cambridge residential development above the lake, it was promised the surface water from the development would be appropriately filtered before being discharged into the lake.
That could have increased the lake’s flow-through and its quality.
But on a council organised bus trip to the development in March this year, a Lakewood spokesperson said the cost of that would be prohibitive.
‘‘Should the developers pay their fair share? I think that a contribution to cleaning up the lake would be a philanthropic act.’’
Pettit said he understood the original desire of the Lakewood developers was to feed stormwater into the lake through the consent process, which didn’t happen.
Waipa mayor Jim Mylchreest backed that up.
‘‘It sounded like a good idea, but because of the cost, obviously they’ve done their sums, and it’s more cost effective to dispose of it on-site, so they are covering their own infrastructure costs.
‘‘The community’s already lost out on a lot of clean water compared to if they’d done as prior suggested and flushed the lake, but the resource consenting requirements made it prohibitive.’’
Dunstan said he thought the council had effectively saved the developers the trouble and cost of putting their hands in their pockets and doing something to benefit the community.
‘‘It was an economic decision, which is out of the council’s hands, to be fair,’’ Pettit said.
Waipa councillor Grahame Webber added another factor to the discussion.
‘‘As an ex-community board member under Rob Feist, about 10 years ago we did a survey of the lake,’’ Webber said.
‘‘We contracted a punt and worked out the average depth of where the mud was, and it’s about a metre-and-a-half of water only in there.’’
He said the board and council discussed putting aerators in the lake, which would have improved the quality of the catchment for fish and ducks, reduced algae and fought bacteria.
‘‘We talked to Waikato Regional Council about taking the sludge out,’’ Webber said.
‘‘They said, ‘No, you can’t move that, it’s full of heavy metals and we don’t want it dumped anywhere’. And the whole cost was in excess of $2 million to do anything with it. It was prohibitive.’’
‘‘So we’re stuck with it?’’ Dunstan said.
‘‘Well, for now,’’ Pettit said. ‘‘I think when it comes on to the agenda, seriously, as a development, just like the swimming pool, and the hall, and the libraries and all the rest of it, which cost big ticket money, to me the community should be engaged,’’ he said.