Quebec Premier Jean Charest on Thursday announced the kick-off of a $5 billion hydroelectric project, the province's largest in a decade.

Charest made the announcement in Montreal.

The Eastmain 1-A hydroelectric project in the north of the province includes the construction of two dams that will be built in the James Bay region on land belonging to the Cree, as well as two hydroelectric generating stations, said CTV Montreal's Tania Krywiak.

Charest had planned to travel to the site of the project to mark the official ground-breaking, but the plan was cancelled on Wednesday, with Charest's staff citing "logistical" reasons for the change in plan.

Instead a news conference was rescheduled for Montreal, a move critics said was designed so that Charest could avoid a confrontation with local protesters at the site.

In order to build the stations, engineers will have to divert up to 80 per cent of the Rupert River, a feature of the project that has upset environmentalists and some members of the Cree community.

"It's very disappointing," Chief Abraham Rupert of Chisasibi, one of three Cree communities opposed to the plan, told The Canadian Press.

"We're feeling we haven't been listened to; we haven't been given a chance to speak."

Rupert said his group proposed a wind energy project that would have averted the flooding of about 400 square kilometres of land.

Chief Matthew Mukash of the Grand Council of the Crees said in a video statement that he had mixed feelings about the project, but he would support it.

"From the initial development of James Bay there have been many social, environmental and health impacts on our people. However we have also been able to build new communities and facilities to meet the growing needs of our population," he said.

Environmentalists and three of nine Cree communities in the area are concerned about the long-term effects of diverting the river, which is vital to the hunting and fishing lifestyle maintained by the Cree community.

Charest stood by the decision to approve the project.

"We continue to listen," he said Thursday.

"We're not insensitive to what is being expressed but it's important to remember that every individual, everyone who wanted to speak to this project in the environmental assessment process, had the opportunity to speak up."

Both the provincial government and Hydro Quebec conducted environmental assessments ahead of the project, and insist they will take every precaution to protect fish stocks in the river and nearby James Bay.

The project was brokered through the Paix des Braves (the Peace of the Braves) agreement reached between former Quebec premier Bernard Landry and Grand Cree Chief Ted Moses, and signed in 2002.

The agreement ensured the Cree maintain their autonomy, but allowed Hydro Quebec to develop a hydroelectric plant in the region.

The government has projected that 27,000 people will work on the project during the years it will be under construction, said Krywiak.

"They say that by the end of it all they're expecting to generate some 900 megawatts of hydro electricity," Krywiak said.

"Just to give you an example, that's being able to produce hydro electricity for about 450,000 residential clients every year."

The project is scheduled for completion sometime between 2009 and 2012.