Two First Nations will be in BC Supreme Court Monday, seeking an injunction to stop work on the Site C dam.
The West Moberly and Prophet River First Nations want construction frozen until a court case opposing the project can be heard.
The First Nations filed a law suit against BC Hydro and the provincial and federal governments in January, arguing that their rights under Treaty 8 and the constitution require the protection of the Peace River Valley.
A previous court challenge against the project failed in 2017.
Tim Theilmann, lawyer for the West Moberly First Nation, said an element of the case includes a report from dam expert E. Harvey Elwin, built on BC Hydro data, which suggests the province’s timeline for the project is flawed.
“The project is in deep trouble,” he said. “It is likely to go at least one year past schedule and BC Hydro itself has said there are major budget implications.”
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The hearing is expected to last three weeks, due to the scope of the challenge.
Thielman said he’s hoping for a decision before BC Hydro starts work in sensitive areas of the project on October 1.
He added that it is concerning the current government is not more transparent about information than the previous one.
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BC Hydro disputes the assessment that the project is off schedule, and says the dam is will be in service by 2024 and will meet its current $10.7 billion budget.
It says independent oversight remains in place for the project, including a Project Assurance Board and oversight from Ernst & Young Canada.
The province isn’t commenting, saying the case is before the courts.
Site C will flood more than 5,500 hectares of land along the Peace River in northeast B.C., creating an 83 km-long reservoir and providing enough power to light up 450,000 homes a year.
The BC NDP decided to proceed with the project last December after a review by the BC Utilities Commission, despite the total cost of the dam climbing from from 8.3 billion to $10.7 billion.