As officials prepare to use helicopters to transport salmon over a rock slide on the Fraser River, crews are beginning work to avoid future landslides in the area.

Fisheries and Oceans Canada says the team will drill 50 holes – at six metres deep and just over six centimetres in diameter - into the rock, aiming to remove the minimum amount of rock required.

"Scaling crews are continuing to remove dangerous rocks on the face of the landslide to provide safe working conditions and to avoid a landslide from occurring in the future," the department said in a news release. "This afternoon a large piece of overhanging rock will be removed through controlled blasting. This rock was not able to be detached through the variety of hand tools used on the cliff face."

The department says it is working with First Nations to make sure archeological values are protected.

A small section of the river in the blasting area will be closed to vessel traffic.

The June landslide created a waterfall on the river, which stopped salmon from making it upstream to their spawning grounds.

The salmon will now be flown over the slide to their spawning grounds upstream.

"There are limitations as to how many fish, of course, we can move at any one time using a helicopter," Andrew J.L. Thomson, regional director for the federal Department of Fisheries and Oceans Fisheries Management Branch, told CTV News. "Nevertheless, it's a start to try and get some of those fish up there while we're pursuing the other options."

Photos captured by the Incident Command Post and posted by the Ministry of Forests, Lands, Natural Resource Operations and Rural Development show the area before and after the slide, including how much rock fell in to the water below.

Big Bar before and after