NDP Leader John Horgan has advised BC Hydro not to sign any new contracts on the divisive Site C hydroelectric dam project.

The $8.8 billion dam will be the third on the Peace River, flooding an 83-kilometre stretch of valley, and local First Nations, landowners and farmers have fiercely opposed the project.

In a letter addressed to BC Hydro's president and CEO, Horgan urges the corporation not to finalize any contracts that do not contain a penalty-free cancellation clause "until a new government has gained the confidence of the legislature."

An agreement between the NDP and Green party was signed earlier this week that would allow the New Democrats to form a minority government, ousting the incumbent Liberals.

The agreement includes a promise to refer the Site C project to the B.C. Utilities Commission to determine its economic viability.

Letter to Hydro CEO

In the letter to Jessica McDonald dated May 31 and written on the letterhead of the official opposition, Horgan said voters elected parties that want the Site C project reviewed or stopped.

"I am concerned at the potential to increase the liability of BC Hydro, BC Hydro ratepayers and taxpayers for new contracts that BC Hydro may be contemplating during this time of uncertainty regarding future governments and what new decisions may be made regarding Site C," the letter said.

BC Hydro couldn't immediately be reached for comment.

Premier Christy Clark said during the election campaign the project promises clean energy and job creation and shutting it down would hurt the province.

The dam is two years into construction and has been approved by the federal government.

Horgan wrote the letter expressing his concern about expropriating people from their homes.

He said although eviction dates have been extended for some families by one month, he believes there is no short term need to force people from their homes.

"We urge BC Hydro to suspend the evictions from these lands and grant a further extension on the timeline so that impacted families can stay in their homes until the future of Site C is firmly determined," the letter said.

The letter was released by the Peace Valley Landowner Association and the NDP confirmed it was sent by Horgan's office.

Ken Arlene stakes

A stand of trees was removed from what used to be the Boons property, before it was expropriated by BC Hydro. The Boons have been given an additional month to vacate the property. (Andrew Kurjata/CBC)