Heritage v hydro debate on Nevis

Above and below: According to recent surveys, the Nevis sustains a fishery which features trophy-sized brown trout. Photo by Otago Fish and Game.

The spotlight will shift from the Clutha River to the Nevis River for the next month, as the fate of hydro-electric development on the Nevis is decided by a special tribunal.

Just as plans for further hydro dams on the Clutha are taking shape, lobby groups and individuals are moving to block any similar development on the Nevis.

The New Zealand and Otago Fish and Game Councils have sought a change to the existing Water Conservation Order on the Kawarau River, asking for a ban on damming the Nevis River, along with conditions on minimum flows.

A special tribunal has been appointed by the Ministry for the Environment to determine whether hydro development on the Nevis River should be banned, or whether the status quo should remain, which would leave the option open for dams on the river.

The application has attracted 248 submissions, most against dams on the river.

The month-long hearing begins this week in Cromwell.

Otago Fish and Game Council chief executive Niall Watson concedes the move may be seen as a "pre-emptive strike", before any power companies apply for resource consent to dam the river.

Under the terms of the existing water order, dams are not prohibited.

Fish and Game and a wide range of other environmental and recreation groups are pushing for tighter controls on potential development on the river, saying it is one of the few remaining "free-flowing" rivers in Central Otago.

On one side of the argument are the anglers, trampers, four-wheel-drive club members, kayakers and skiers, who maintain the Nevis Valley would be spoilt if a dam was permitted.

New surveys of the river had highlighted its importance as a trout fishery, they said.

"The trout habitat afforded by the Nevis is outstanding in that it sustains a headwater trophy brown-trout fishery based on resident fish that have an average size that is far greater than most brown trout fisheries in Otago," the councils said in their application.

A dam would threaten the many historic goldfields sites, the landscape values and the wilderness characteristics of the area, many submitters said.

On the other side of the argument are local and regional authorities, power companies and a few individuals, all of whom say the existing water order provides adequate protection of the river.

Any proposed hydro development would have to apply for resource consents from the Central Otago District Council and the appropriate water consents from the regional council.

Those processes were an adequate and appropriate way to determine whether any hydro development was successful, submitters in favour of the status quo said.

Given the push towards using renewable sources to generate electricity, it was unwise to rule out hydro development on the Nevis, the power companies said.

The Department of Conservation and Ministry of Economic Development (MED) have also entered the debate but are remaining neutral.

In its submission, approved last year by David Parker as the Minister of Energy, the MED said it was important to preserve opportunities for hydro development.

However, energy developments should not occur at any cost, and consideration had to be given to the adverse environmental effects associated with such ventures, it said.

A hydro scheme on the Nevis would generate up to 45MW, which would "make a modest contribution to the increased generation capacity required to satisfy demand," the MED submission said.