The West Moberly First Nation says it is reviewing a B.C. Supreme Court judgment against its Site C legal challenge.
On Friday, Justice Robert Sewell dismissed an attempt by West Moberly and Prophet River First Nations to quash the province's environmental certificate for the $8.8-billion dam.
West Moberly and Prophet River argued the province was wrong in making its decision to approve the dam, as it would infringe on their treaty rights.
"We are obviously disappointed with the judgment and are in the process of reviewing it with our legal counsel," Chief Roland Willson wrote in a statement to the Alaska Highway News.
"It is hard to believe that it is legal for the government to decide to destroy a major river valley that is central to the exercise of our Treaty rights without first making sure that its decision does not infringe those rights.
"Apparently all the government needs to do is make sure we have been consulted before making decisions that may actually be a violation of our Treaty. This couldn’t have been what our ancestors intended when they entered into the Treaty based on the government’s promise that there would be no forced interference with our way of life," Willson said.
In his judgement, however, Sewell said provincial ministers "made no error" in issuing the certificate without determining whether or not the project infringed on the two First Nations' treaty rights.
"The legislature did not intend to vest the Ministers to decide the complex question of whether the project was an infringement of the petitioners' Treaty 8 rights," he wrote.
"The procedures set out in the (law regarding environmental assessment certificates) are simply inadequate to permit determination of the issues framed by the (First Nations) in this proceeding."
The matter of treaty infringement could not be determined in a judicial review. It would need to go to a civil claim trial to determine if treaty rights were infringed.
"It is apparent that there is a considerable degree of conflict in the evidence which can only be resolved at trial," Sewell wrote.
In July, Sewell also dismissed a case brought forward by the Peace Valley Landowner Association, which argued the province did not give adequate consideration of economic recommendations made by the joint review panel appointed to review the dam and its impacts.
Further court challenges against the dam are set to continue this fall.
On Nov. 17, B.C. Supreme Court will hear arguments from West Moberly and Prophet River about permits issued for the first phases of dam construction.
BC Hydro has said it will continue to work with impacted First Nations to address their concerns.