Six submissions have been received so far on plans to raise Lake Roxburgh by 60cm to boost power generation.
Contact Energy has applied to the Otago Regional Council to raise the lake's maximum operating level from 132m above sea level to 132.6m.
The council had received six submissions by late yesterday afternoon but the final number would not be confirmed until next week, ORC senior resource officer Mathew Bell said.
Four of the submissions opposed the application, while two supported it, one with conditions.
In its application for a variation of its water permit, Contact said a heightened lake level would boost power generation and allow it to alleviate New Zealand's current shortage of electricity generation capacity.
The dam was capable of operating safely at that level, it said.
The existing flood rules for the Roxburgh dam would be altered to make allowance for the heightened level and the change in level would have an "insignificant" effect on the amount of sediment in the lake, Contact said.
There would be no effect on the lake's water quality and negligible effects on the river's ecology. The effect on amenity and recreational values would be minor, it claimed.
However, last week the Alexandra District Flood Action Society said it would oppose the plans to raise Lake Roxburgh, and a commercial operator on the lake also voiced concerns about the impact of the change on recreational users.
Contact owns and operates the dam, located on the Clutha River. Lake Roxburgh stretches from Roxburgh to Alexandra, so the raising of the lake will have an impact on the shoreline and beaches between the two towns.
