The Federal Court of Appeal has dismissed a lawsuit from two B.C. First Nations trying to prevent the Site C dam project from going ahead.

The Prophet River and West Moberly First Nations argue flooding 5,500 hectares of the Peace River valley to make way for the hydroelectric project infringes on their constitutionally-protected treaty rights.

A lawyer for the First Nations argued the federal cabinet should have determined if Site C infringes on treaty rights prior to issuing permits allowing the project to go ahead.

Lawyers for the federal government and BC Hydro countered that decisions about treaty rights should be determined in court, not by cabinet.

A panel of three judges led by Justice Richard Boivin agreed, writing that the governor-in-council (cabinet) "does not possess any expertise and is not equipped to determine contested questions of law and complex factual issues" and that it "cannot exercise adjudicative functions".

Site C construction

Prep work for construction of the Site C dam takes place along the Peace River in northeastern B.C. in June 2016. (Justin McElroy/CBC)

Instead, rulings on treaty rights should include "a full discovery, examination of expert evidence, as well as historical testimonial and documentary evidence." 

The case was dismissed with costs.

The ruling does not determine whether or not treaty rights are, in fact, violated by Site C.

It does, however, state the federal government is allowed to issue permits for projects like Site C without first discovering if the project violates treaty rights.

The Site C dam will flood approximately 5,550 hectares of land in northeast B.C. currently occupied by a number of ranchers and farmers, along with traditional Indigenous land and heritage sites.

West Moberly Chief Roland Wilson has said the project will render the valley "useless". 

The Mikisew Cree First Nation in Alberta also fear Site C will dry out Wood Buffalo National Park - A UNESCO World Heritage site.

BC Hydro and the B.C. Liberal government say the dam will be needed to provide a source of sustainable, clean energy for the province.

Read the full ruling: