VANCOUVER - A British Columbia First Nation has launched a lawsuit alleging its treaty rights have been violated by decades of development - a legal challenge that could affect the province's planned Site C hydroelectric dam project, as well as the expansion of mineral, oil and gas extraction in the province's north.

The lawsuit, filed in B.C. Supreme Court by the Blueberry River First Nations, follows several recent court decisions involving aboriginal rights, including a landmark Supreme Court of Canada last year that expanded how much influence First Nations can exert over development.

The Blueberry River band's lawsuit argues the cumulative effect of development in its traditional territory has harmed its way of life in violation of Treaty 8, which was ratified in 1900.

“There are vast dark zones in our territory where we are no longer able to practise our treaty rights,” Chief Marvin Yahey told a news conference Wednesday.

He said oil and gas wells, pipelines and clearcuts had changed the land so much it would be unrecognizable to the band's ancestors and that development continued to shrink the group's territory at a rapid pace.

The band's traditional territory includes the proposed location of the Site C hydroelectric dam, an $8.8-billion project approved last year that the provincial government government says will generate 1,100 megawatts of electricity.

Construction is scheduled to start on Site C project in June, but it's one of the developments the band wants halted.

The statement of claim contends the band's lands and its rights to hunt and fish have been eroded cumulatively over multiple decades, something other Treaty 8 bands have not argued in court before.

John Rich, the group's lawyer, said the band tried for twenty years to address its concerns by negotiating with the province but without success or progress.

He said the lawsuit was a last resort.

“The Blueberry River First Nations' back is against the wall,” said Rich. “They are suing to get a remedy from the courts that they have not been able to get through negotiation.”

None of the allegations have been tested in court.

The provincial government did not make anyone available for an interview.

In an emailed statement, Aboriginal Relations and Reconciliation Minister John Rustad described the lawsuit as “unfortunate,” and he said the government had negotiated development with all Treaty 8 First Nations, including Blueberry River.

Other northeastern B.C. First Nations covered by Treaty 8 have used the courts to slow down or stop the building of the Site C dam, requesting that environmental approvals or decisions be overturned because of inadequate consultation.

The Blueberry River lawsuit and previously filed cases related to Site C follow a string of court decisions that have redefined First Nations' rights when it comes to development projects in their territories.

The most significant case was released by the Supreme Court of Canada last year, when the high court granted B.C.'s Tsilhqot'in people title to 1,750 square kilometres of land.

Gordon Christie, who specializes in aboriginal law at the University of British Columbia, said last year's Supreme Court of Canada decision isn't directly related to the current because, unlike the Blueberry River band, the Tsilhqot'in did not have an existing treaty. Most of B.C.'s First Nations bands never signed treaties with the government.

Still, Christie said the Tsilhqot'in decision could affect the Blueberry River case later on.

“These are things that will get argued, probably, if this gets into court,” said Christie, who directs the university's indigenous legal studies program.

He said there had been “lots of litigation” since 2004 from First Nations aimed at getting them a greater say in development and resource decisions and policy.

Christie estimated there had been hundreds of cases, but he said most First Nations had limited resources for long legal struggles, making the courts “a very uneven playing field.”