Risks of dust storms and dry bores have Lake Hāwea residents fighting Contact Energy’s plans to lower lake levels under new fast-track laws.
The gentailer sought to drop the Central Otago lake by up to 2m, taking it to 336m above sea level, and down to 330m in emergencies.
The company said the plan would help supply for when electricity demand is high and rainfall is low, and also told residents it would help reduce emissions and keep power prices down.
But Guardians of Lake Hāwea’s John Langley told 1News: “They’re looking after their shareholders and returns to investors by way of dividends, it’s not about public good.”
Residents said they would pay the price, concerned that extreme dust storms of the 1970s would return as the lakebed is exposed.
“The farmers were having to wash their wool because they were full of dust but it was a constant irritant for all of us,” said resident Ray Macleod.
“Our machinery got covered in dust, your tractors, your sheds, everything got just coated in dust, and it was just a terrible situation.”
There was also a risk for Hāwea Flat groundwater levels currently under assessment.
Hundreds of people in homes and the school relied on the aquifer water.
Resident Meredith Smith was concerned that “bores could run dry, if the aquifer drops as a result of the lake level dropping”.
Contact Energy head of hydro Boyd Brinsdon said: “It is incomprehensible that our actions would mean that kids at school can’t have drinking water. We need to resolve that.”
But overall at this stage, he said: “We don’t believe there would be significant impacts.”
Nationally, hydro generation was down 6.8% year-on-year at the start of winter – one reason was low hydro storage.
Contact Energy’s plans would generate power for an extra 10,000 households a year, the company estimated,
Brindson said it was “pretty well known” that wholesale electricity prices were very high last winter due to a dry period.
“We had substantial inflows into the Hāwea catchment, we ended up spilling about 70,000 megawatt hours of electricity generation that could have been utilised if this consent condition that we’re wanting to apply for had been in place at that time.”
But it is early days for the project, while applying to be in the fast track legislation, a decision to be made at the ministerial level, before a second application with expert evidence seeks approval.