Independent Hearing Commissioners appointed by Environment Canterbury have rejected a proposal to take water from a North Canterbury stream for irrigation and power generation.
The Kakapo Brook runs through Glynn Wye Station and co-applicants Rooney Group - owner of the station - and Mainpower proposed taking up to 1600 litres per second, to fill two large storage dams on the farm totaling 1 million cubic metres.
The water would be used for irrigating 500 hectares of the high country property and providing hydropower generation.
Fish and Game Advisor Scott Pearson said the proposal was contrary to the regional plan which prohibited taking water from rivers and the decision sent an important message.
"This area is treasured by anglers here and overseas, as it includes internationally recognised trout fishing rivers such as the Hope and Boyle," he said.
"The increased pressures to intensify once extensively grazed properties was seeing irrigation and higher stocking levels creep into the high country, right throughout Canterbury.
"The proposed amount of water in terms of allocation was approximately 10 times what would normally be taken from a small river of this size."
He said effects such as significant volumes of water removed from the mid-section of the river, sustained low flows, increased wather temperature and algal growth, and a reduction in available aquatic habitat for larger fish were highlighted.