Central Otago power company Pioneer Generation will oppose an application by the New Zealand and Otago Fish and Game Councils to the Minister for the Environment to prohibit damming and diversion of the Nevis River.
The councils want the Water Conservation (Kawarau) Order 1997 altered to protect the Nevis River, which flows from its source at the southern end of the Garvie and Hector Ranges, to its confluence with the Kawarau River about 50km northeast.
That order gave some protection to the Nevis but did not preclude the river being used for hydro-electric power generation.
A special tribunal has been set up to consider the application.
Pioneer Generation chief executive Peter Dowling said yesterday the company would be making a submission to the tribunal on the basis the Nevis clause in the 1997 order should stand.
The river is highly regarded because of landscape, recreation and historic values, and for its trout fishery.
Alexandra gold miner Bob Kilgour, who has mining rights near the upper Nevis River is welcoming any moves to protect the lower Nevis.
"The lower Nevis has outstanding landscape and I wouldn't think any mining operators would like to see that area under water," Mr Kilgour said.
"The historic lower Nevis is more valuable and more accessible through Bannockburn.
"There is a lot more in there including the historic cemetery, the old part of the town, tailings and bits of dredges. They [tourism operators or Doc] could make a lot of it," he said.
Flooding the lower Nevis would wipe out the access road.
Mr Kilgour also pointed out that sluicings on the hill were quite dramatic.
"The Red Rim Reef was exposed on the western flank of the Nevis reserve. How those old timers got the water up there is amazing."
There were significant tailings along the base of the hill, plus the sluicing elevators, and flooding could inundate those.
"Those need to be protected for future mining because there's actually still a significant resource along the base of the hill of the lower Nevis that has some potential for future exploitation of the minerals."