Genesis Energy has pushed back on claims that it may have contributed to the flooding that hit Wairoa last week.

The power company, which runs the nearby Waikaremoana Power Scheme, said it had deliberately lowered the level of the lake in anticipation of the heavy rain that Cyclone Gabrielle brought.

The Gisborne Herald reported that Wairoa residents were concerned the power company might have made a poorly-timed decision to open a floodgate at its Lake Waikaremoana dam, creating the sudden surge of water that spilled over the banks of the Wairoa River.

Interim chief executive Tracey Hickman said she was comfortable that there was no impact on the flood-damaged town from the company’s operation of the scheme.

Genesis Energy's interim CEO, Tracey Hickman. Photo / Supplied

“The flooding at Wairoa was not as a result of our operation of Waikaremoana,” she told the Herald.

“During the peak of the flood a week or so ago, we were discharging around 40 cumecs (cubic metres per second) - which is a little less than is required by our resource consent,” she said.

“That was around one per cent of the peak flow that was experienced at Wairoa during the flooding,” she said.

In the lead-up to Gabrielle, Genesis had been able to lower the lake’s level by about 6 per cent.

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 “We had seen it coming and, of course, it came on the back of a very wet period over many weeks and months beforehand, but we had seen that particular rain event.

“We were able to put a ‘hole’ in the lake and significantly reduce the outflow.

“We have continued to do that with even less discharge ever since.”

Hickman said running the scheme was nevertheless a balancing act as the region needed power.

 “That is the one asset now – given the constraints in the area - that is keeping the lights on for the East Cape,” she said.

Hickman acknowledged that it had been “hideous” time for people in the area following the cyclone and that the company’s data was open for review.

Genesis, 51 per cent owned by the Government, earlier reported a 42 per cent increase in its operating profit for the first half to $298m.