In a written update this week, Contact Energy head of generation Boyd Brinsdon said new data had changed plans to further drop lake levels.
The company is seeking fast-track consent to boost renewable energy generation by lowering the lake’s minimum operating level from 338m to 336m.
The plan, which has attracted controversy, originally proposed to drop levels down to 330m in extreme cases.
But the company has now revised the contingency limit to 334m.
Locals spoken to yesterday by the Otago Daily Times were not buying it.
Guardians of Lake Hāwea chairman Geoff Kernick said he was not surprised by the change, saying it was likely a way for the company to seem more co-operative with the community.
"We’ve always hypothesised that Contact were asking for the 6m contingency as something that they would be prepared to give up," Mr Kernick said.
"It’s a massive number and the fact that it gets people very excited and alarmed, I don’t think that’s a mistake."
Mr Brinsdon said recent modelling indicated a larger drawdown of the lake was not needed to support national energy security.
Further, the change "aligns with community concerns around the environmental and operational risks", he said.
Mr Kernick said Contact had never used the contingency storage they had and so it was "not really giving up anything".
The company had done little to ease concerns regarding lowering the lake’s minimum operating level to 336m — dust storms, aquifers, biodiversity loss and recreational amenity loss were still prominent issues.
Upper Clutha Angling Club president Simon Gibb suggested the company’s changed proposal for a contingency limit was just a "negotiating ploy".
"It’s almost a red herring."
Hāwea Flat resident Meredith Smith said changing the proposed contingency level was simply not good enough.
Ms Smith is part of a committee that helped run a local water supply and she expressed concerns that lowering the lake would mean a high risk to groundwater, leading to the widespread failure of bores.
During a packed public meeting last month many others flagged this issue, referencing a 2023 report prepared for the Otago Regional Council that found dropping Lake Hāwea’s water levels to 330m would likely cause a substantial decline in groundwater.
Ms Smith had said any drop in present lake levels would put the water supply at risk and emphasised that the community would continue the fight against the proposal.
"We’re still waiting for the decision on the fast-track referral application," she said.
"And if that takes the go ahead, then we’re going to have an even bigger fight on our hands." — Additional reporting RNZ
