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Community Remediation

Mount Polley built and managed an on-site fish hatchery in 2018

After the spill, a population monitoring program on Polley Lake indicated there had probably been a reduction in the age class of the population of Rainbow Trout (as upper Hazeltine Creek was the main spawning area for these trout). There was spawning observed in Frypan Creek at the north end of Polley Lake, however it was noted to be a much smaller habitat. The Mount Polley Environmental Team (MPET) recognized it was important to allow the fish to spawn in Hazeltine Creek, but the Habitat Remediation Working Group (HRWG) had concerns whether the spawn in the reconstructed Hazeltine Creek would be successful.

The MPET developed a backup plan. With guidance provided by Minnow Environmental and David Petkovich (Aqua-culturist), over 11,000 Rainbow Trout fry were raised in an on-site fish hatchery in spring 2018. Eggs were harvested and fertilized from some of the local Rainbow Trout that had returned to upper Hazeltine Creek to spawn.

The fertilized eggs were incubated in trays so temperature, flow and dissolved oxygen levels could be regularly monitored. Water intake was sourced from below the thermocline in Polley Lake in order to maintain cooler water temperatures.

Egg trays in Mount Polley on-site Rainbow Trout hatchery [2018]
Egg trays in Mount Polley on-site Rainbow Trout hatchery [2018]

Within two months, the eggs hatched into alevins (yolk-sac fry) and within another two weeks the yolk sacs were completely absorbed.  Throughout the incubation stage the eggs were counted, and unfertilized eggs removed.

Fish tray showing Rainbow Trout eggs hatching [June 2018]
Fish tray showing Rainbow Trout eggs hatching [June 2018]
Rainbow Trout fry in shallow ponding tanks [early July 2018]
Rainbow Trout fry in shallow ponding tanks [early July 2018]

The fry were then transferred from the incubation trays to shallow rearing tanks. When the fish reached their target biomass, they were transferred into deeper rearing tanks, and from there released into the Polley Lake watershed.

Mount Polley hatchery rearing tanks. [summer 2018]
Mount Polley hatchery rearing tanks. [summer 2018]

The MPET and Minnow Environmental released over 11,100 Rainbow trout fry from the hatchery into Polley Lake on September 25 and 26, 2018. The adipose fins from each fry were clipped as a means of tagging (identification). On the second day, students, parents and a teacher from Columneetza Middle School’s Greenologists / Enviro Club based in Williams Lake assisted with the Rainbow Trout fry release

Mount Polley strongly encourages Polley Lake fishers to report if they catch fish with a clipped adipose fin to gabe.holmes@mountpolley.com. This will help the MPET determine how successfully the hatchery trout are surviving. Thank you!

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Video

Mount Polley Remediation Story

This is the story of Mount Polley Remedition – from tailings spill to environmental recovery

Katie: “My name is Katie McMahen. I was born and raised here in Williams Lake and I was a member of the environmental team here at Mount Polley for a number of years. Although it was a really devastating event, as scientists we want to learn what we can out of this work that’s going on and so we’re studying methods for restoring functioning forest ecosystems, methods for rehabilitating the soil, and trying to improve best practices, really. Since day one, we’ve been doing a ton of environmental monitoring and really prioritizing fixing up the creek.

“So I love the forest, and I love working and rehabilitating the forest, so some of the coolest work we’ve been doing is not just the replanting of trees, but trying to trying to create the right conditions for those trees to thrive. So, managing the tailings, doing some techniques to really make nice little sites for the trees to grow and so that they had the proper soil conditions.”

Mount Polley remediation staff on site near Hazeltine Creek
Mount Polley staff have been working diligently for years to restore habitats, ecosystems, and the environment at Mount Polley and affected sites. The Mount Polley Remediation story is one of turn-around, innovation, and Canadian pride.

Gabriel: “My name is Gabriel Holmes, and I grew up in Likely, British Columbia, and I’m an environmental technician here, I’ve worked here since 2011. I’m really proud of reintroducing the fish into the creeks – there’s a whole bunch of things I could go on and on – but reintroducing fish into Hazeltine Creek was a real milestone, the success of the spawning last year of the rainbow trout and Hazeltine Creek, a real milestone. The vegetative communities that are developing in our terrestrial landscapes in riparian areas and then of course this year, seeing a number of sockeye salmon in Edney Creek. I’m really proud to see that occur because that’s one of our end goals that we were trying to accomplish and to see them utilizing the system today, it’s fantastic.”

Katie: “I’m super proud of the work that we’ve done here. One of the biggest challenges has just been the scale of the work that we’ve had to do, and so considering it’s only five years now since the breach, just the sheer amount of work that’s been done in those five years is amazing. When I look back it feels like way longer because I can’t believe how much we’ve done.

“We’ve really set a high precedent for what needs to happen following an incident like this and that the type of work that can be done and should be done to clean up sites. There’s a lot of information that needs to get out there about what what’s the actual environmental conditions and the fact that we have thriving rainbow trout in the creek and tons of wildlife and animals using the habitat that we’ve created. It’s going to take some years for everything to grow, but these ecosystems are well on their way to recovery.”

Mount Polley environmental technician surveys sites near Polley lake. Remediation efforts have come a long way and are almost complete. The recovery project has cost Mount Polley’s parent company more than $70 million.