Recent rains cause new erosion problems at Site C

BC Hydro says there are no stability or safety concerns after recent rains caused new cracks to open on the north bank of the Peace River above the Site C construction zone.

Recent photos of the north bank circulating online show the new cracks appearing near the site of the Site C work camp and viewpoint road, and extending down a considerable portion of the hill between various access roads, and above where river diversion tunnels are being excavated. BC Hydro has characterized the issue as surface erosion due to the recent rains.

"Localized erosion is typical during excavation activities of this size and nature, and it’s something we’ve been monitoring since the start of construction," spokesperson Dave Conway said.

"Work is continuing on the drainage channels that will manage future water runoff on the north bank slope. We anticipate this work will be completed in the coming months."

After a bone dry spring, the Fort St. John area has recorded roughly 42 millimetres of rain so far in July, and recorded 65.6 millimetres in June, according to data from the airport weather station.

Last summer, a week of rain forced BC Hydro to close the public viewpoint overlooking the construction site for several months to repair and upgrade ditches in the area.

Two tension cracks that emerged on the north bank in early 2017 pushed back a planned 2019 river diversion to 2020 and added $610 million to the project's cost—adding weight to opposition arguments that the site is too unstable to support a dam and will continue to drive the project over its $10.7-billion budget.

Construction crews have been excavating the north bank to remove historic landslides in the dam site area, though, slope instability caused a work safety stoppage in July 2017 and forced main contractor Peace River Hydro Partners to file for a 435-day schedule delay the following month.

Email Managing Editor Matt Preprost at editor@ahnfsj.ca.

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Erosion on the north bank of the Peace River above Site C.
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Erosion on the north bank of the Peace River above Site C.
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