Otago Regional Council has confirmed it will review aspects of the Clyde Dam resource consent.

Every five years the council has a three month window in which to notify Contact Energy - which owns and operates the dam - of its intent to review consent conditions.

The council notified the electricity giant yesterday with just a day left in the window.

The council will be reviewing conditions relating to the impact of the dam's operation on the Kawarau Arm of Lake Dunstan.

Lake Dunstan was formed at the confluence of the Mata-Au/Clutha River and Kawarau River by the damming of the Mata-Au at Clyde.

For almost three decades it has provided recreational and amenity to the community of Cromwell.

But the Kawarau Arm has in recent years become a shallow, and at times smelly and dangerous mess, due to silt that used to wash down from the Kawarau River and onwards down Mata-Au being being trapped and accumulating for three

decades.

Last month, RNZ reported the council had issued an abatement notice against Contact over the Landscape and Visual Amenity Management Plan - the road map for how the Clyde Dam's effects on the Kawarau Arm would be managed.

Today's confirmation of a review followed pressure from community groups, who said the electricity giant was not fulfilling its obligations as a corporate citizen.

Otago Regional Council regulatory and communications general manager Richard Saunders said councillors were advised of the decision to review the consent this afternoon.

The scope of the review was "very narrow" and only dealt with conditions relating to the Landscape and Visual Amenity Management Plan.

"We believe there is an opportunity to provide greater clarity to all parties about the expectations of what is to be included in the plan and the process by which it is updated and approved," Saunders said.

Clyde Dam. Photo: Tristanb, CC BY-SA 3.0

Contact Energy had acknowledged receipt of the notice to review.

In addition to the review, the council would continue with a full audit of all Contact's hydroelectricity-related consents.

That audit might identify additional adverse effects not currently mitigated through the conditions of consent, Saunders said.

"We acknowledge there are a number of questions raised around the current Clutha hydroelectricity scheme. Further evidence is required before ORC could consider a broader review of the scheme."

It would be at least a month before any decision on public input into the review was made.

A Cromwell community group lauded the decision to review.

Lake Dunstan Charitable Trust chair Duncan Faulkner said today was a good day for the lake and the community.

"It makes us feel heard. It's taken a long time to get to this stage ... and it's taken quite a lot of courage for the ORC to press the button to do the review. But they've done it and they are listening to the community," Faulkner said.

"We've now got a really good opportunity to work together with ORC and with the Central Otago District Council and Contact Energy to get better outcomes for the lake, and I do believe everyone is on board."

Otago Regional Council's decision to review the consent followed months of pressure by the trust and other community representatives, who had raised concerns about the state of the Kawarau Arm in recent years.

Now it was imperative the community was heard about its views on the consent, Faulkner said.

"The input from the community is incredibly important - they expect to be listened to and there's a multitude of different opinions around what a good lake looks like.

"We've just undergone the biggest community engagement exercise in the history of Lake Dunstan so we've got some great data we can feed back into and Cromwell certainly isn't short of having a lot of enthusiastic people that are willing to have

their opinions heard and shared."