Site C FAQ

Site C FAQ


Site C instability

BC Hydro admits that the massive dam foundation structure it has poured on the south bank of the dam, a roller-compacted concrete buttress, is showing signs of serious foundation issues. BC Hydro’s talk of attempting to stabilize it with various forms of anchors and new drainage methods indicates that the buttress is sinking and/or shifting, as well as experiencing water pressure. This buttress supports key parts of the dam: the spillways and the generating station/turbine hall. BC Hydro admits it does not know how to fix the problem, nor how much trying to fix it might cost. It describes the situation as code red. See BC Hydro’s reports or read commentary on them by Vaughn Palmer in the Vancouver Sun: Site C Dam has a huge problem and it’s not Covid-19.

There is no bedrock at Site C, only an unstable shale that is several hundred feet deep at the dam site and along the valley. This shale is deceptively hard when dry, but soft, swelling and cohesionless when exposed to water. This shale is the cause of the region’s famous landslides. It is also the reason many experts and engineers urged the BC gov’t not to proceed with the dam.

Read a superb summary of Site C’s geotechnical problems, including interviews with engineers, by investigative journalist Ben Parfitt: “Site C’s Radical, Risky Makeover – BC Hydro says it has just discovered new, costly problems for the megaproject. In fact, engineers have known about them for decades.”

The Long Answer

In December of 2019 BC Hydro discovered serious stability problems with the Site C dam. Hydro only disclosed this fact to the public in two long-overdue Site C quarterly reports that it finally released on July 31, 2020 —the Friday of a summer long weekend. In the reports, BC Hydro admits there are serious foundation problems with the roller-compacted concrete buttress that is the foundation of the dam’s spillways and generating station (turbine hall etc).

BC Hydro admits that it does not know how to solve the problems but it talks about some form of stabilization: anchors, shear keys (like a wedge into underlying material to brake movement), and extra drainage which suggests that they need to solve water ingress and/or relieve hydrostatic pressure building up in the shale geology under and behind the buttress.

Most of these geotechnical problems were long predicted by engineers as well as locals in the Peace region familiar with the area’s instability.

The dominant underlying geology of the Peace River Valley is a unique dark grey shale that some engineers just call Peace River shale. It’s a compacted marine Cretaceous shale that is deceptively hard when dry—hard enough that it must often be jack-hammered—but when exposed to water it becomes soft, swells, loses cohesion and separates. The swelling and lack of cohesion are the reason for the Peace Valley’s frequent landslides also the disintegrating roads. This shale is many hundreds of feet deep at Site C. When BC Hydro speaks of “bedrock” at Site C, it is this shale they are speaking of.

A confusion over the meaning of “rock” partly arises because geologists often refer to shale as “bedrock,” even though it only consists of tiny rock flakes, but engineers generally do not—or at least should not.

A further problem with this shale is that it is currently in a state of “rebound” after being released from the compression of the weight of glaciers thousands of feet deep during the last ice age. If you place millions of tons of concrete on rebounding shale, the shale will be likely to compact again, producing settling. This may be what we are seeing under the buttress at Site C.

That this shale has extremely low compression strength was actually admitted in an October 2016 paper by several engineers working for the main engineering contractors for the dam itself, Klohn Crippen Berger (KCB). (Note: one of its authors is former lead engineer of the Site C dam design team, John Nunn. He is a former KCB engineer who is now on the BC Hydro board as well as the Project Assurance Board that the BC NDP government formed to oversee Site C. He is thus effectively checking his own work and questions have been raised about conflict of interest.)
The 2016 paper was published in the Canadian Dam Association Quarterly magazine in summer 2017.

Site C L-shaped dam design

As the dam’s engineers described in the paper above, Site C’s unique L-shaped dam design—a design that has never been tried with an earthfill dam before—was devised in late 2010/early 2011 to avoid attaching the dam to known weak layers of geology on Site C’s south (right) bank. Instead of affixing to the bank, the dam takes a dogleg and situates the spillways and generating station on that short side of the L, all sitting on a concrete buttress. Yet that buttress is now slipping, even though this foundation area was meant to be more stable than the side of the south bank.

Many engineers see no way to solve the problems of the shale’s low compression strength and the risk of water penetration. BC Hydro says it’s looking into 3 solutions: anchors (to what?), a shear key (something to stop 1.2m cubic metres of concrete from moving? Jam the key into what?) and extra drainage (clearly water is building up behind the buttress and creating pressure against it). BC Hydro needs to be more transparent about the exact signs of trouble and how much the fix would cost—but they admit they don’t know how to fix it or how much that would cost.

Slide history:
• A heavy rain undermined the footing of the Peace River Bridge at Taylor in 1957 and collapsed it. It had recently been built by the US Army Corps of Engineers for the Alaska Highway. A review of that bridge failure by U. of Alberta engineering professor R.M. Hardy analyzed the geological cause.

• Slides near Site C have on occasion been large enough to block off the whole river, impressive given that the river is often called the “Mighty Peace.” Near Site C, one such slide occurred at Bear Flat around 1890 or 1900, and another was the 1973 Attachie slide at the confluence of the Halfway and Peace Rivers (would be submerged in the future Site C reservoir). That slide is shown here, shortly after the river managed to carve a channel through the slide.

Attachie Slide, Peace River, 1973

Veteran BC hydro engineer Vern Ruskin, who worked on the construction of the early Peace and Columbia dams and is one of the few engineers in BC with actual BC dam experience, is on record as saying that Site C can’t be guaranteed to be safe. His main worry wasn’t just that there was no bedrock under the dam and it could fail, but also that a slide into the Site C reservoir could create an overtopping wave that would collapse the dam (common cause of dam failure especially with earthfill dams). His view was that filling the reservoir would force water into the shale and likely cause numerous slides along its banks. See Vern Ruskin’s official submission to the BCUC Site C review in 2017.

For a useful 2013 compilation of information about Peace Valley instability and the dangers of Site C, see this letter from Arthur Hadland, a former director of the Peace River Regional District.

Also see a superb summary by investigative journalist Ben Parfitt of Site C’s geotechnical problems with interviews with engineers: “Site C’s Radical, Risky Makeover – BC Hydro says it has just discovered new, costly problems for the megaproject. In fact, engineers have known about them for decades.”

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No. Large hydro dams destroy rivers and ecosystems, and their reservoirs release significant levels of methane. Reservoirs also produce and concentrate high levels of methylmercury—you may have seen signs on their banks warning you not to eat the fish or to limit their consumption. Modern alternative technologies are not only cleaner and greener than dams, they are also much cheaper, and cheaper electricity helps encourage the switch from fossil fuels to electricity.

The Long Answer:

Hydroelectricity is neither green nor “clean” (clean is a lower bar than green). A growing number of jurisdictions no longer class hydroelectricity as green and consequently won’t pay as much to import it. Why?

  • It’s now known that reservoirs are major emitters of methane and CO2, which are byproducts of the decomposition of plant and other life submerged under reservoirs.
    Hydroelectric dams emit a billion tonnes of greenhouse gases a year, study finds
    The hydropower paradox: is this energy as clean as it seems?
  • Hydro dam reservoirs also create high concentrations of methylmercury, which poisons fish and water. Most BC reservoirs features posted signs warning visitors not to eat the fish they catch or to limit their consumption of it. As with methane, methylmercury is a byproduct of the anaerobic decomposition of drowned plant and other life. This damage is long-lasting, too: when dams are later decommissioned, the mercury-filled soils they leave behind must be treated as toxic waste, so converting valleys back to agricultural land or natural habitat is not that simple.
  • Dams also desiccate downstream areas and deltas, leading to death of ecosystems and further release of CO2 and methane. In the case of the Site C dam, the threat is to the Peace Athabasca Delta, already impacted by two prior dams on the Peace River (WAC Bennett and Peace Canyon).
  • The concrete in mega-dams has a massive carbon footprint. Site C will require millions of cubic metres of concrete to be poured.

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The short answer: Site C has more significant adverse environmental effects than any project ever examined in the history of Canada’s Environmental Assessment Act.

The Long Answer

The adverse environmental impacts of the Site C dam include:

  • destruction of habitat for more than 100 species already vulnerable to extinction, including bird, plant, butterfly, bee and mammal species—this at a time when scientists warn we are facing a biodiversity crisis.
  • extensive loss of very old forest including old-growth boreal forests, key for caribou and other species, along 100 km of the valley inside the flood zone
  • destruction of ancient tufa seeps
  • destruction of key animal and bird breeding areas like the famous Watson Slough
  • desiccation of the downstream Peace Athabasca Delta and UNESCO site, Canada’s largest national park Wood Buffalo Nat’l Park
  • impacts on fish and other species in or dependent on the river, via interruption of river flow and methylmercury concentration


NOTE! The federal government of Stephen Harper issued the environmental permits for Site C during the election writ period, which is highly irregular. The Trudeau government was well within its rights to overturn those irregular permits when it came to power, but it chose not to. Trudeau, who is clearly close to SNC-Lavalin, has stated publicly that he wants to see scores more dams ‘across the North” as part of the federal government’s clean energy initiatives. On whose land, and on melting permafrost? When dams are more environmentally damaging than the alternatives?

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No. BC has a massive electricity surplus and this situation won’t change for many years. We already have enough electricity to switch every car in BC to an EV, as BC Hydro itself admits. We can also take back our Columbia River Entitlement that’s the same amount of electricity as Site C for far less money. We’re currently paying IPPs not to produce electricity. Meanwhile the prices of renewables are falling daily. When we do need more electricity one day, there will be cleaner and cheaper ways of getting it fast.

The Long Answer

We won’t need more electricity in BC for a very long time. Demand is flat and will remain so for many years, even with EVs. And we can’t and won’t transition to electricity from fossil fuels if electricity is too expensive to switch to.

– BC Hydro itself has stated that we could switch all cars in BC to EVs on BC’s current grid (BC Hydro’s EV expert Alec Tsang to CBC:
EVs largely charge at night, when we can barely give electricity away. And cars will increasingly be charged on local energy grids.

BC has an electricity surplus:
– BC has a massive electricity surplus. We are so awash in electricity that we are effectively paying IPPs (Independent Power Projects on many BC rivers) not to produce it.

And not only do we already have a surplus, we can additionally take back our Columbia River entitlement from the US, which gives us almost the same amount of electricity as the Site C dam, at a small fraction of the cost of Site C.

The economics of exporting power don’t work
Hydropower is expensive to produce, meanwhile BC exports electricity for peanuts. Even before the expense of Site C, we are currently selling power to other jurisdictions on the spot market for far less than it costs us to produce it. Site C will make this situation far worse.

Site C will produce electricity at a high cost of at least C$ 0.12/ kilowatt-hour ($120/megawatt-hour). But to trade (buy or sell) electricity on the Mid-Columbian (“Mid-C”) hub costs US$ 0.018/KWh in 2020. (That’s a median price of 1.7 cents/ KWh, or $17/MWh). In short: it costs 12 cents to produce Site C electricity, but we can only sell it across the border for 1.7 cents. There is a growing surplus of power in the Pacific Northwest due to the proliferation of renewables, hence the low price.

This mismanagement—building an over-expensive dam when we didn’t need it, all so corporations can win contracts—means that BC is needlessly making power over-expensive for our own residential and commercial consumers even while we have a massive supply of it. This has the effect of actually discouraging consumers and businesses from switching to electricity from fossil fuels—it’s simply too expensive to switch.

By the time we really need more electricity, prices of renewables will have plummeted even further, and we can bring new electricity and storage online quickly as we need it. As every business grad knows, timing is everything in investments.

Alternatives are cheaper (and greener)
Even if we did need the energy, cleaner renewables are cheaper. Recent estimates from top energy project finance expert Eoin Finn showed that BC could get the same energy from a combination of geothermal, wind and solar for $7 billion, and the cost of those technologies has plummeted since then. Site C is now well north of $11 billion and many experts say it could head over $20 billion.

We won’t successfully switch from fossil fuels to electric if we make electricity too expensive

Hydroelectricity is much more expensive to produce than electricity from renewable alternatives like wind, geothermal and solar. Site C is so expensive to build that experts say hydro rates will have to be doubled to pay for it. Higher prices actually slow down the transition from fossil fuels to electricity, as residential and business consumers cut their power use to save money and also decline to switch from fossil fuels to electric. This phenomenon of consumer choice is known as elasticity.

Energy conservation and efficiency:

  • Innovations that increase efficiency – such as the replacement of incandescent bulbs with compact fluorescents and now LEDs, cause energy consumption to plummet. This trend will continue, and not only in lighting.
  • Electric heat pump heating systems are far more efficient than ’natural’ gas (20% vs 80%) so it’s not a one-to-one replacement per unit of energy. Many more innovations are coming.
  • Conservation measures can and will save BC power too. BC Hydro has not even seriously pursued conservation yet, unlike most jurisdictions in North America.
  • The commonly heard refrain that “we will need colossal amounts of electricity to replace fossil fuels” is a profligate way of thinking about energy that is inherited from our habits around fossil fuels.

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Short answer: Yes. Site C represents the largest removal of Agricultural Land Reserve (ALR) land in BC history. BC has very few good agricultural valleys, and even fewer valleys of the Peace’s top agricultural quality: ~100 kilometres of extremely deep fertile soils, a perfect east-west orientation, and extremely long sunlight hours in summer. With the climate and agricultural crisis in California and other sources of BC’s food imports, BC food security means we will need every farming valley we have, especially this one.

The Long Answer

Class A farmland is rare in BC. Also rare is an east-west valley, the ideal orientation. The Peace Valley is hot and sunny in summer and enjoys extremely long growing hours. Peace farmers can even grow peaches, canteloupe and watermelon. As climate change desiccates lower latitudes, the North will become a very important zone for food production. BC cannot spare this valley.

We often hear: “If the 100+ kms of the Peace River valley that Site would submerge is such great farmland, why is it not more intensively farmed now? There’s currently only a little hay and some market gardens and not much more.”

The answer to this objection is that while there are numerous farms in the valley, more intensive farming has been discouraged because although Site C was rejected multiple times in the past, BC Hydro has never removed its lands from the Site C flood reserve. No farmer would make significant improvements to the land given the perpetual uncertainty that land might be expropriated for a dam at some future point. BC Hydro owns significant property in the flood reserve and has slowly bought up most of it. Some farmers have decided to keep farming until the last minute; but this valley can never be properly farmed until Site C is not only stopped but removed from the books permanently.

Top BC agrologist Wendy Holm showed in her expert testimony to the Site C Joint Review Panel that the Peace River valley if farmed to its potential could fill all the produce needs of over a million British Columbians. This would also mean that produce from the south and California would not have to be shipped thousands of kilometres north. Read her summary in the Georgia Straight.

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As Chief Roland Willson of West Moberly First Nation (one of the communities most impacted by the dam) has repeatedly said, consultation is not consent. It’s not even consent when First Nations sign benefit agreements with BC Hydro, since many sign under duress. Most Treaty 8 Nations do not want to see the Peace River valley destroyed and most acknowledge that the dam violates Treaty 8 and Indigenous rights. Benefit agreements are signed with BC Hydro out of a need to gain some advantage from a project that is clearly going ahead anyway, a project that most nations do not have the resources to stop or successfully fight in court. This is a familiar pattern repeated all across Canada, as financially strapped Indigenous communities realize that projects are unstoppable even before consultation, and agree to benefits payouts as the least terrible path.

Despite the difficulty and expense of taking governments and crown corporations to court, West Moberly First Nation continues its challenge to Site C in BC Supreme Court, with the respondents being BC Hydro, the BC government and the Gov’t of Canada. It is represented by Sage Legal and eminent BC expert on aboriginal law Jack Woodward. A separate case launched by Blueberry River First Nation seeking damages for cumulative impacts of development and infringement of their Treaty 8 rights includes impacts from Site C.

Across Canada, large dams disproportionately impact Indigenous communities, flooding vast tracts of land and poisoning the water and food supply. As with Muskrat Falls, Keeyask—and the other large dams of BC, Manitoba and Quebec—Site C will violate Indigenous rights. Please read Amnesty International Canada’s Site C Dam: Human Rights at Risk.

Site C lies in Treaty 8 territory. Treaty 8 guarantees a continuance of the traditional way of life, both in terms of hunting and fishing and cultural and spiritual activities.

Under Treaty 8 BC government has the right to push projects through if there’s a demonstrated public need. There is no demonstrated public need for Site C’s electricity, and furthermore alternatives to the dam are cheaper and lower in impact, so provincial and federal governments cannot justify the dam in terms of Treaty 8.

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Yes. While BC Hydro has claimed that our dams are built to withstand quakes over 5M (magnitude), it has not publicly acknowledged the serious threat that constant, repeated, low level quakes and vibrations pose to dams that already have pre-existing stability problems.  The Peace region is being subjected to thousands of fracking quakes every year and the number is growing. In January 2020 a major exposé by Ben Parfitt revealed that the Peace Canyon dam, which lies downstream of WAC Bennett dam and upstream of Site C, was cracked by fracking quakes in 2007. Parfitt interviewed Dave Unger, BC Hydro’s Construction Manager for the whole Peace region, who was inside the dam when it happened. It’s a harrowing account. The BC Ministry of Energy oversees the Peace River dams and the fracking operations that threaten them, a conflict that remains unresolved. Read Thousands of Quakes, Tied to Fracking, Keep Shaking the Site C Dam Region.

See map of fracking quakes near Site C in a recent 2-year period. Site C is in pink near top left; the fracking quakes are the cluster of nearby circles. Red circles show the quakes listed in the Canadian federal database (NRCan) while blue and green show newly released data from other sources (industry, academia). See the recent CBC report New study detects thousands of earthquakes in B.C. Peace region, most linked to fracking. Please also note the purple lines showing natural faults in the region. The presence of these faults poses a risk because even if small fracking quakes doesn’t damage a dam on their own, they can “critically stress” a natural fault, especially when they’re aggregated, setting off a far larger natural quake. This is in fact what happened when a 4.5M fracking quake was set off in December 2018, felt strongly in Fort St John, caused the evacuation of Site C, and was felt for 100 kilometres.

Fracking quakes near the Site C dam

A significant body of investigative journalism on the risk of fracking to the Peace River dams has been carried out by journalist Ben Parfitt, largely in the news outlets The Narwhal and The Tyee, and in op-eds in the Vancouver Sun and Province. His work has also been published by the Canadian Centre for Policy Alternatives. Mainstream media has been relatively silent on this major ongoing story. Selected articles by Parfitt and others on this issue:

Peace River Frack-Up
The Well From Hell
Peace Canyon dam at risk of failure from fracking-induced earthquakes, documents reveal
Inside BC Hydro’s lost battle to protect major hydro dams from fracking earthquakes
Thousands of Quakes, Tied to Fracking, Keep Shaking the Site C Dam Region, by Andrew Nikiforuk in The Tyee
New study detects thousands of earthquakes in B.C. Peace region, most linked to fracking CBC

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SNC enjoys profitable no-bid contracts at Site C. Oil and gas executive Gwyn Morgan was SNC-Lavalin’s Chair when Site C was first being planned, and was very close to both BC Liberal premiers Gordon Campbell and Christy Clark, becoming the latter’s senior advisor. SNC-Lavalin was a major donor to the BC Liberal party at the time. Please read The secretive role of SNC-Lavalin in the Site C dam by Sarah Cox, author of Breaching the Peace: The Site C Dam and a Valley’s Stand against Big Hydro (UBC Press).

The Long Answer

While SNC-Lavalin is not the main Site C contractor, it was one of the first two at Site C, providing early engineering design services. When Premier Gordon Campbell first began to talk about Site C, SNC was a major donor to the BC Liberal party and its Chair was Gwyn Morgan, a close friend and advisor to the premier. Did Morgan convince Campbell to resuscitate the oft-rejected, long-shelved dam project? 2008-2009 was also the height of SNC-Lavalin’s international bribery activities, for which it was finally banned by the World Bank in 2013 thereby losing significant global contracts. Whether the company saw this ban coming when the idea to resuscitate Site C was hatched or not, SNC wanted lucrative public projects at home in Canada. When Gordon Campbell stepped down in 2011, Morgan became senior advisor to new premier Christy Clark. To this day, SNC enjoys profitable no-bid contracts at Site C.

Note that other engineering and construction corporations working at Site C have also been charged with corruption. Both Acciona and Samsung, who together form Peace River Hydro Partners, have a history of corruption. Like SNC-Lavalin, Acciona was banned from projects by the World Bank.

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