Monday, December 05, 2022

BC
The keepers of Cheewaht: Restoring an ecosystem for generations to come

By Alexandra Mehl

Cheewaht Lake, BC - Off the rugged west coast of Vancouver Island, inland from the West Coast Trail, is a quiet and remote lake brimming with vibrant ecosystems. From trumpeter swans to black bears, the Cheewaht Lake watershed provides a home for dense and rare biodiversity.

The Cheewaht Lake watershed is on the traditional territory of Ditidaht First Nation, who, for thousands of years, managed the area from villages along the coast at the mouth of the Cheewaht River.

According to the Government of Canada website, in 1973 logging practices began to pose a threat to the pristine ecosystem, which concerned Ditidaht First Nation and environmental groups. Cheewaht Lake and salmon-bearing streams became a part of the West Coast Trail Unit of the Pacific Rim National Park Reserve to protect the area.

Though the Parks Canada protected Cheewaht Lake from industrial activity, logging swept through up to the park boundary, which would impact the Cheewaht Lake watershed years later.

Cla-oose Riverkeepers


Historically, the village of Cla-oose managed the salmon population traveling to Cheewhat Lake, and further upstream to spawn.

“It was… managed well, pre-contact,” said Paul Sieber, the Ditidaht First Nation’s natural resource manager.

They harvested the salmon with fishing weirs and traps. They would methodologically select harvest for the village, and then release the females, said Sieber.

The fishing weirs and the way that the salmon were managed fed the people in the village of Cla-oose for thousands of years, he continued.

Sieber recalls stories that he heard from elders.

“There was a designated riverkeeper, a Cheewaht riverkeeper family, at least one,” he said. “They collectively maintained it [at] the head.”

“[They had] a certain family or combination of families that would actually manage the fishery,” continued Sieber. “They just managed it for the benefit of all, and for the fishermen. They weren't allowed to overfish it.”

The area not only holds cultural significance for Ditidaht because of the salmon, but for the many traditional resources it provided for the people, said Sieber.

“It’s very important to the people,” he said. “It’s so culturally important as a food resource.”

Merging Boundaries

When Mike Wright, a registered professional biologist and owner of M.C. Wright and Associates Ltd., began research at Cheewaht Lake watershed in 1984, he said the streams were in “pristine form” prior to industrial logging.

That same year the industry logged northeast of Cheewaht Lake up to the park boundary, though it didn’t impact Sockeye tributaries, said Wright. In 1986 logging in the upper reaches of a stream leading to Cheewaht Lake started, he continued. This forestry activity affected S-2, one of the three streams that feed the lake.

According to the Government of Canada, at this time Ditidaht First Nation limited their fishing capacity in the area to preserve the salmon population.

“There's usually a 10-year window before we really start to see things change,” said Wright.

However, in 1989, a sediment wedge and log jam ruptured, which sent gravel and woody debris downstream. This destroyed an area in the stream where coho and sockeye spawned, including the eggs in that area, explained Wright. The woody debris collected at the confluence between S-1 (Stream 1) and S-2, which interrupted the waterflow of S-1 and S-2, he continued.

“We didn't see heavy impacts, everything we're experiencing was incremental,” said Wright.

Another issue that emerged from logging was the formation of avulsions, the creation of a new water channel, said Wright.

“You're taking water that would have been more concentrated to transport sediment, and now you're losing that because it's going elsewhere,” said Wright. “There's all these things that get layered on that make incubation success very difficult.”

B.C. Timber Sales hired a specialist who helped determine and design a way to manage the debris jam and sediment transport, he said.

“There's a lot of investment by industry to get the study, [and] get enough information, so that we could start talking about restoration,” said Wright.

The same specialist was hired by Western Forest Products to design a sediment trap for S-3, he said.

The sediment traps were built at the top of S-2 and S-3, where gravel and woody debris would be held and emptied. Wright said that the basin filled almost annually.

“What we had to do is get to a point where we were controlling that sediment so that we could start to plan to work down below,” said Wright.

“[It] was a real wake up, then the populations were at high risk of being extirpated,” noted Wright, reflecting upon 2014.

When the finger pointing stopped


In 2017, the Cheewaht Restoration Working Group was re-established to collaborate on ways to restore salmon spawning streams in the Cheewaht Lake that had been impacted by logging.

The working group is made up of a diverse group of representatives. Participation comes from the Ditidaht First Nation, Nuu-chah-nulth Tribal Council/Uu-a-thluk, Parks Canada, Fisheries and Oceans Canada and the Nitinaht Hatchery, the Ministry of Forests, Lands and Natural Resource Operations (South Island), British Columbia Timber Sales, Western Forest Products, the Teal-Jones Group, biological consultant MC Wright and Associates Ltd., as well as the environmental non-governmental organization West Coast Aquatic.

“When we created the working group we said, ‘Look, we all know how we got here’,” said Wright. “The finger pointing stops…but we all came together to work towards a solution.”

Sieber said that it was an intermittent process to come together and discuss restoration.

“Without the industry and the First Nations, and DFO [representatives] coming together, that funding wouldn't have been approved,” said Sieber. “They needed the background and a justification to move forward with the project.”

Parks Canada received a letter from Ditidaht nation urging them to address restoration in the creek, said Yuri Zharikov, an ecologist for Pacific Rim National Park Reserve.

“We put together a proposal for the work and in formulating the proposal, we've been working closely with the nation and other land managers in the area,” said Zharikov.

Parks Canada funded the 1.1 million dollars to cover the cost of the project, according to the Government of Canada website.

“What we didn't know is whether the landscape around the park could be maintained and kept in such a way that no more major impacts would occur,” said Zharikov. “That was the main purpose of the table, to kind of coordinate everybody in a way that would ensure the success of the restoration.”

The regions that had been previously harvested, causing impacts in the Cheewaht Lake watershed, are no longer being logged, said Ryan Abbott, a registered professional biologist at M.C. Wright Associates.

Restoring a system to its natural state

In 2020, the restoration team, which consisted of Ditidaht, Parks Canada, M.C. Wright, Roc-Star Enterprises Ltd., and Nitinaht River Fish Hatchery, hit the ground running beginning phase one of the onsite restoration of S-1, S-2, and S-3.

When the project started Abbott described the streams as “choked with gravel.” First, they would need an excavator to remove any excess gravel. They began by building a temporary corduroy road, so that the excavator could be brought to the remote location, he explained.

The project was completed with no environmental catastrophe and with limited access to equipment, explains Abbott.

The team removed a total of 3,206 square metres of gravel, which is over ten times the capacity of the sediment basins at the top of S-2.

“Not only do you have to remove the gravel and try to make the creek stable again. But you have to establish a split where the two creeks diverge from one another in a way that's going to actually last,” said Abbott.

The same specialist that designed the sediment basins at the top of S-2 and S-3 also designed a flow splitting structure at the confluence of S-1 and S-2.

“We had to try and figure out a way to make a stable split in this creek, where you're going to actually re-establish those historic two channels that are going to share the flow between one another,” said Abbott.

In phase two, which occurred in 2021, the team focused on improving the flow splitter, removing features that contributed to blockages, and anchoring woody debris along the streams.

“What wood does, one of its big functions in a creek like this, especially a creek that can move a lot of material…it's the driver of the habitat,” said Abbott.

Abbott explains that by anchoring wood along the stream, they are able to facilitate the creation of long-term pools because of the increased water pressure and ability to scour gravel.

“We tried to do what we could with the materials that were on site,” said Abbott. “We also tried to keep with the aesthetic of a park, where you have this kind of natural look.”

The fluvial process, a healthy system

The consistent delivery of gravel that continues from the sediment trap about one kilometre upstream from the anadromous barrier is what made this restoration project particularly complicated, said Abbott.

“Gravel will continue to come, over time. And that's just part of what they call the fluvial process,” he said. “Rivers, they move more than just water…they basically transport the land, off mountains and onto the beaches.”

Every system transports sediment and gravel, however the problem occurs when the system is out of balance, said Abbott.

Abbott said that to continue the movement of gravel, they ensured that there isn't as much wood or features in the way. He predicts that the streams will have excess gravel for the next 10 to 20 years.

The flow splitter, at the confluence of S-1 and S-2, has a V shape to it in order for woody debris to deflect into either stream and continue traveling, said Wright.

“This should get back into some form of balance,” said Abbott.

Salmon returns

According to the Government of Canada Website, in October 2020 salmon started returning to the Cheewaht Lake watershed to spawn in the streams.

This year hundreds to thousands of fish have been filling the creeks to spawn, while black bears in the area have been feasting.

Since restoration Parks Canada has continued to monitor the area for the immediate results of restoration, said Zharikov. They frequent the streams counting the active fish and carcasses in and around the streams to determine the lifespan of the salmon in the creek, he explains.

Some of the fish are tagged, and when they are scanned it allows Zharikov to understand “what an average individual in the population does,” he said.

This information will then get analyzed, he explained.

“It's a big run this year…the fish are waiting,” said Zharikov. “Almost lining up, there’s just too many of them.”

In coordination with Parks Canada, Ditidaht’s Stewardship and Monitoring program will continue to check on the restored streams and surrounding ecosystems, said Abbott. They will monitor things like rainfall, water quality, stream levels, and invertebrates.

“This project’s really about Ditidaht. And it was important that we made sure that the sockeye run was going to be there for future generations,” said Wright.

In four years, the eggs from this season will return as adults, and spawn in the Cheewaht watershed’s streams.

“We’ll see the results in four years,” said Sieber. “First results.”

Alexandra Mehl, Local Journalism Initiative Reporter, Ha-Shilth-Sa

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