A dam-safety specialist at BC Hydro repeatedly raised concerns about the proximity of fracking operations to dams in northeastern B.C. and the risk of damage from fracking-induced earthquakes, according to documents gathered through Freedom of Information requests — but the concerns were dismissed by his superiors.

The internal documents were obtained by the Canadian Centre for Policy Alternatives and included in a report titled Peace Canyon Frack-Up, in which author Ben Parfitt says fracking — and the earthquakes it can cause — may threaten dam infrastructure.

Some of BC Hydro's biggest dams are found in the Peace Region. It's an area dotted with natural gas operations — many of which now rely on hydraulic fracturing, or fracking, to extract the gas. The utility operates its huge W.A.C. Bennett Dam and Peace Canyon Dam on the Peace River and is building its Site C Dam on the same river.

The documents, which have been shared with CBC News, show BC Hydro dam safety specialist Scott Gilliss repeatedly raising the issue of earthquakes caused by fracking, the increase of nearby fracking activity and dam safety with superiors.

The documents show that Gilliss is told his "broken record" warnings have been heard and brought to the "highest level" — provincial ministers.

But according to the documents and Parfitt's report, that's as far as it went. Gilliss was told it was a "dead issue."

Previous warnings

In 2016, CBC News covered Parfitt's work and similar warnings he uncovered at the time, but the resource policy analyst says he has gathered much more information in three years worth of additional FOI requests.

"We have learned that there are much greater risks to BC Hydro's dams, and in particular its Peace Canyon Dam, should earthquakes occur near the dams," he said. "The Peace Canyon Dam has known foundational problems, that there is an increased risk to damage to that dam by nearby earthquakes."

In November 2018, a 4.5 magnitude earthquake — believed to be caused by fracking — was felt at the Site C Dam construction site which led to a brief work stoppage and inspection to ensure there was no damage.

When Parfitt's warnings were first aired, Chris O'Riley, then deputy CEO of BC Hydro, said concerns about risks from fracking were overblown. Now, despite the new documents, the utility's position is unchanged.

Fracking has been connected to what is known as induced seismicity — typically small earthquakes caused by human activity. (Andrew Cullen/Reuters)

"We don't believe there's any concern for the safety of our dams," said Bob Schubak, director of dam safety at BC Hydro. "We would acknowledge that a very close earthquake would cause some damage to our equipment."

But he said damage would be limited to shutting down power generation — not anything that would compromise the structural integrity of the Peace Canyon Dam which is just upriver from the town of Hudson's Hope.

Peace Canyon Dam issues

Parfitt said that BC Hydro ought to immediately undertake seismic upgrades to ensure disaster doesn't strike at Peace Canyon Dam.

According to Schubak, the utility is already considering work to bring the dam, which was completed in 1980, up to modern seismic standards. He said upgrade projects are expected in the late 2020s.

Parfitt also called on the B.C. Oil and Gas Commission, which regulates fracking operations, to ban all fracking within 10 kilometres of hydroelectric dams. Parfitt suggests any fracking within a 15-kilometre range beyond that should be specifically authorized after careful consideration.

The commission said in a written statement that there are no fracking wells within five kilometres of any BC Hydro dam, and none within 10 kilometres of the W.A.C. Bennett or Peace Canyon dams.

Listen to interviews with Parfitt and Schubak by clicking play on the audio below.

Ben Parfitt of the Canadian Centre for Policy Alternatives says he's uncovered multiple letters and reports showing BC Hydro is worried fracking-induced earthquakes could damage dams in the Peace River region, but the utility's safety manager says concerns are overblown. 17:23

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