Site C Dam – BC Hydro

Site C, just outside Fort St. John, BC, was first considered as a potential hydro power site in the 1950s. In the late 1980s the project was rejected by the BC Utilities Commission as being too expensive, controversial, and not in the best interest of the public.

In 2010 the BC Liberal government (under Premier Christy Clark) passed the Clean Energy Act, which removed the BC Utilities Commission’s authority to cancel projects deemed to be not in the public interest. BC Hydro could now proceed without interference and independent oversight. In place of the BC Utilities Commission, project oversight would now be provided by the Project Assurance Board, which included board members employed by BC Hydro. In 2014 the Government of British Columbia announced that the project would proceed at a cost of $8.3 billion.

In 2017, the BC Liberal government was replaced by the NDP. Newly elected Premier John Horgan, who had been a vocal critic of the project, ordered a review by the BC Utilities Commission. It was ultimately decided that too much had been spent at this point to turn back so the project continued.

In late summer of 2020 reports surfaced that there were problems with weak material underlying the powerhouse and spillway as well as both riverbanks. The foundation had actually slipped a few centimeters downstream in 2018 but that did not become public until two years later. In response Horgan appointed former Deputy Finance Minister Peter Milburn to conduct a review of the project and write a report on the escalating costs and safety issues stemming from the foundational problems.

A condensed/redacted version of Milburn’s report was made public six months later and was critical of BC Hydro in that he found that they repeatedly downplayed geotechnical risks and cost estimates when reporting to the government prior to approval of the project.

After publication of Milburn’s report, the BC government hired two independent dam experts (France and Hoeg) to assess the unprecedented plan proposed by BC Hydro for reinforcements using pilings to stabilize the powerhouse/spillway foundation. The report concluded that the foundation reinforcements were viable based on information they received from BC Hydro, but they made it clear that there were no guarantees and they assumed no liability. The information provided by BC Hydro that was used to compile the report is also not available to the public.

We now know the geology under Site C consists of shale which becomes mud when exposed to water. It also contains vertical and horizontal fractures as well as bedding planes which allow the passage of water throughout the material. Any excavation or disturbance can potentially create a path for water to infiltrate and weaken the foundation. Considering that the dam will be holding back a reservoir 200 feet deep, if anything goes wrong the consequences could be severe. The fact that there is no real bedrock under the site was not revealed until the project was well under way and after billions of dollars were spent.

On June 8, 2021, BC Hydro community relations manager Dave Conway, Site C project manager Mike Clark and planning director Martin Jaseck accepted an invitation to virtually attend a County of Northern Lights council meeting to answer questions on downstream safety concerns.

One question asked was “What would have happened if the slippage of the foundation had occurred after the reservoir had been filled?” Mr. Clark assured council that the movement would be “minimal.” He also went on to describe the foundation piling reinforcements as “elegant”. Mr. Clark could not identify another dam project on the scale of Site C that was built on similar shale material nor could he give an example of another similar structure that had to be reinforced using pilings.

Mr. Conway refused to answer any questions regarding the Milburn report. He also would not answer any questions regarding liability for potential downstream damage in Alberta stemming from BC Hydro’s actions.

During the meeting, County of Northern Lights Council requested three informational items from BC Hydro: the full unredacted Milburn report, the unredacted France and Hoeg report and technical Advisory Board reports from 2021.

The Milburn report was provided in a more complete form that had been originally made public but the appendix which contains all the information used by Milburn to compile the report was redacted. This represents 296 pages of material.

The unredacted France and Hoeg report was not provided. Instead, a summary of the report and select excerpts that BC Hydro deemed worthy of release were shared. In the report summary it was revealed that material under the earth fill dam itself was not tested or sampled prior to diversion of the river. As with the Milburn Report the vast majority of information used to compile the report is being withheld.

The Technical Advisory Board reports for 2021 were not provided. What was provided were reports from 2020 with all the names of the meeting attendees redacted. The 2021 reports would inform how the foundation reinforcements are progressing.

Latest cost estimates for Site C are at $16 billion which is double the figure provided when the project was announced, and the completion date of 2025 is two years later than originally forecast. Sarah Cox at Narwal magazine has reported that engineering giant SNC Lavalin, which has been financially supportive of the BC Liberal Party, has received $453 million from BC Hydro from 2010 to 2018. Much of that is from no bid contracts.