Expert witness stood down

In a surprise development at yesterday's Environment Court hearing into TrustPower's application to build a hydroelectric power scheme on the Wairau River, Marlborough District Council expert witness Peter Constantine was stood down part-way through giving evidence.

The council senior planner was being cross-examined by Save the Wairau lawyer Mike Hardy-Jones when Judge Gordon Whiting called a break to confer with court commissioners.

At the time, Mr Hardy-Jones was arguing that the Marlborough District Council-appointed panel, which previously considered TrustPower's application, granted the company consent outside water allocation rules set out in the Wairau Awatere Resource Management Plan. The panel's decision was appealed, resulting in the Environment Court hearing now underway in Blenheim.

The issues were complex and he was having difficulty understanding the cross-examination while following relevant sections of the plan, said Judge Whiting. He asked Mr Constantine to return to the stand in two weeks.

Earlier, Fish & Game Nelson-Marlborough manager Neil Deans said his organisation accepted that there may be room to move in designing a hydroelectric scheme for the Wairau River which would satisfy concerns about effects on fish, game birds and angling.

The difficulty would be identifying flows which would sustain habitats in and below the affected reach.

Evidence to the court was not sufficiently credible to provide confidence in recommended flow regimes, said Mr Deans.

Ideally, all parties with an interest in the application would work towards agreeing on potential adverse effects and threshold trigger levels, he said. However, he was unsure whether the parties could reach consensus and of the time this would take.

Reducing the distance between TrustPower and Fish & Game would be difficult when there were so many uncertainties about the biological consequence of altered flows, he said.

There was also disagreement on objectives, said Mr Deans. For example, TrustPower expert witness Greg Ryder argued that habitat loss of 30 per cent as a result of a changed flow regime would be acceptable. Studies on other catchments had suggested about 10 per cent would be more appropriate.

The aquatic management plan prepared by TrustPower did not contain the detail needed, he said. For example, a single bullet point flagging potential effects on fish communities was inadequate.

Another difficulty Mr Deans had was: "What happens if things in it aren't adhered to? Does that mean the consent holder is in breach? My understanding is that they would not be."

Mr Deans' credibility as an expert witness was attacked by TrustPower lawyer Christian Whata, who suggested that as an advocate for Fish & Game he lacked the independence required.

Mr Deans acknowledged the potential conflict of interest in his role as an expert witness to the hearing and a Fish & Game manager. However, as his expert views and those of the Fish & Game council were aligned, this was not the case, he said.