Concern high lake levels are causing environmental damage at Waikaremoana

Home Bay at Lake Waikaremoana . . . boaties and anglers are seeing the destruction of wildlife and submerging of camping areas at the lake, while the iwi authority which manages the lake reckons low levels encourage the invasion of Lagarosiphon weed. File picture

Waikaremoana Boating and Fishing Association is concerned about damage to the environment it says is because of management of the lake levels by Genesis Energy.

The energy company runs the Lake Waikaremoana hydropower scheme.

Association chairman David Parker and members Dave Aitken and Alex Crichton say they noticed these issues before the cyclones in January and February.

Areas of the lake that were once able to be camped on are now submerged.

“We want to see the environment being preserved and enhanced for future generations,” Mr Crichton said.

“Over the past two to three years the lake has been consistently high which has compromised planting around the banks. Is this acceptable?” he said.

Mr Parker said several years ago Tuhoe had pushed a reset on freedom camping around the lake because of what they believed was destruction of forest, fauna and banks around the lake.

“The continual high lake levels maintained by Genesis have had a far more significant impact on the forest and fauna than humans camping around the lake,” he said.

The association has worked with and had conversations about the lake levels with Te Uru Taumatua (TUT), Tuhoe’s iwi authority.

Kirsti Luke, of Te Uru Taumatua, said when Genesis lowers the lake, Lagarosiphon weed invasion occurs and gets out of control.

“This exposes the weed to the sun and next minute it’s a full-on invasion. It sucks oxygen out of the water and lake life suffers.”

She said boating nets, which cost a lot to maintain and are not weatherproof, have been installed. Genesis had contributed nothing to these measures, she said.

“They (Genesis) are 110 percent profit-driven thus holding the water until prices suit is something they can only get away with at Lake Waikaremoana because they cannot store water in their river assets. We bear the brunt of that through the ecological damage it causes,” she said.

“We have been responsible for Te Urewera and are 72 percent owners of Lake Waikaremoana and they have contributed zero — even to the impacts they have directly caused,” she said.

Genesis has stated the average level of Lake Waikaremoana over the past two years has been 582.83m, within the consented range of 580.29 to 583.29m.

“High lake levels were due to the number of successive and severe weather events in the catchment,” Genesis chief wholesale officer Tracey Hickman said.

This was highlighted by Genesis data which showed the average inflow to Lake Waikaremoana was higher in the 12 months to June 2023 than any other 12 month period since records began in 1930, and almost twice the long-term average, she said.

“Genesis takes seriously its responsibility to operate the Waikaremoana Power Scheme within strict resource consent requirements that take into account the communities that use the lake, live along and downstream of the scheme, and the environment.

“Knowing the effect of high inflows on Lake Waikaremoana, Genesis reduced the lake level by 6 percent in the days before the onset of Cyclone Gabrielle.

“During the cyclone and through subsequent rain events Genesis continued to reduce the lake level to the best of our ability.”

She said the water release contributed less than 1 percent of the water that flooded Wairoa.

The remaining 99 per cent of water which flowed through Wairoa township came from tributaries below Genesis’s lowest point of control, she said.

Due to the volume of inflows, the lake level remained higher for longer, but had since returned to levels within the consented range.

“Our team at the power scheme are members of the community, and understand at a personal level how our resource consents must balance the effects of high rainfall on both the lake and those who live downstream.”

Ms Hickman said the company would be contributing to the independent review commissioned by the Hawke’s Bay Regional Council that is seeking to understand the factors that led to the flooding in the region.

Wairoa District Council is also starting their own independent review. Ms Hickman said they were looking forward to seeing the framework of this and how they could contribute.

“We remain open to constructively participating in discussions regarding management of the Waikaremoana Power Scheme for the benefit of renewable electricity generation for Aotearoa and those who use the lake, live along and downstream of the scheme, and for the environment.”

Dave Aitken said Genesis maintained it took seriously the strict resource consents, “but even at 50cm below the maximum consented level damage is being done to the shoreline with erosion on the banks and damage to native trees growing there, some of which are dead”.

“I think there should be a review of the requirements of the resource consent relating to the maximum level and the time spent at this mark,” he said.

Mr Parker said he hoped Genesis Energy would listen to these concerns and invite the association to be involved when the lake levels are changed.