Opponents of a plan for intensive dairy farming in the upper Waitaki region have told a consent hearing the irrigation would irreparably destroy the landscape.
Three companies are applying to establish 16 new farms in the area, with plans to house nearly 18,000 cows in cubicle stables part of the year.
The MacKenzie Guardians environmental group has told a panel of commissioners that the applications are an inappropriate use of an outstanding natural landscape.
Lawyer Phernne Tancock said the proposal would have a significant effect on the ecology and destroy the landscape which was a drawcard for tourists and film companies.
The hearings began two months ago and will continue next year.
One of the companies, Five Rivers Limited, whose director is Kees Zeestraten, wants to establish seven dairy farms with up to 7000 cows at Ohau Downs near Omarama.
Another dairy company owned by Mr Zeestraten, Union Station Dairies in Southland, was this year fined $25,000 for breaching discharge consents.
Green Party co-leader Russel Norman says granting the Five Rivers consent applications would be madness, given Mr Zeestraten's history.