The dam proposed by BC Hydro would be the third on northeastern B.C.'s Peace River and would flood about 55 square kilometres of land along 83 kilometres of river valley.
The Canadian Environmental Assessment Agency conducted hearings in December and January, submitted its report to the federal government last week and is expected to post the document online Thursday.
Horgan says it's a good project, except for the fact B.C. doesn't need the energy, First Nations oppose it and the dam would destroy so much agricultural land.
He says he wants a third party to answer some legitimate questions like when will the province actually need the power and how much should the people pay for it.
The Crown utility has said the dam is a clean, cost-effective source of much-needed electricity for British Columbia.
"The BC Liberals have made a mess of BC Hydro," says Horgan. "We have 28 per cent rate increases coming down the pipe. We have deferred debt. We have long-term debt, and we have projects that are wildly over budget."
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