In Part 1 of the Holiday Farm Fire Series, we looked at the community issues which arise from a serious wildfire. Part 2 looks closer at the environmental issues.
These articles were written as part of a series because the environment and the communities along the McKenzie River are intimately connected – what affects the landscape around these towns immensely affects the livelihoods and lifestyles of residents of Blue River, Vida, Finn Rock, and Nimrod.
For generations, families of the McKenzie Valley have lived within dense green forests and enjoyed hiking and fishing the river and local reservoirs. These same resources and natural beauty are also what draws tourists to the area, supporting local restaurants, inns, rafting guides, and fishing outfits. In addition to burning hundreds of homes and dozens of businesses, the Holiday Farm Fire left the forests of these communities charred and smoldering. The path to recovery of the landscape will be long, but wildfires’ ecological impacts are complex and in a seemingly bleak situation, there are hopes for regrowth and enhancement of what was already there.
Soil
Just like how communities of the McKenzie Valley are linked to the environment, every aspect of the environment is linked to the soil. That rich, damp, earthy smell you detect when walking into the forests of the Pacific Northwest is primarily created by the soil under your feet. Healthy soil in an intact ecosystem is made up of rocks, minerals, and dead organisms, but also microbes, bacteria, and fungi. The soil in our forests are alive. But after a wildfire like the Holiday Farm Fire, that soil becomes dirt, which is defined as soil that is dead, or has lost its ability to support life.
In high intensity fires like the Holiday Farm Fire, the soil is so baked by the heat that it becomes hydrophobic, meaning water does not penetrate it like normal healthy soil in the region. Image a pan of brownies that spends too much time in the oven; you see and smell the smoke, and pull out a pan of rock-hard brownies with a burnt, blackened crust. This is essentially what happens to the earth in places where fire intensity is high.
“There are two types of burn severity,” explains Dr. Daniel Leavell, State Fire Specialist and Associate Professor in the Fire Program at Oregon State University. He describes the two ways of measuring burn severity as quantifying damage to vegetation and damage to soil. These two different burn severities are important, because they tell different stories about ecosystem effects and help predict how a landscape may recover post-wildfire.
Leavell has worked around wildfires for over 30 years and says that back in the 1970s when he first started studying fire ecology, the gradient of burn severity included around 10-20% both low and high intensities in different places within a wildfire burn perimeter. This means that the majority of the fire was of moderate severity, which does not damage the soil as severely and allows for some vegetation to survive.
Today’s fires are reversed, with 60-70% of wildfires now burning at high severity and smaller fractions of earth being burned by low-moderate heat. Speaking specifically of the Holiday Farm Fire, Leavell said, “It not only burned hot and fast, it burned with a higher overall severity impact than most fires prior to this fire season.”
Landslides
If you have ever driven along the McKenzie Highway, you would have appreciated the gorgeous scenic route along the river and through dense green forests growing on the steep, glacier-carved slopes of the valley.
With the vast majority of the Holiday Farm Fire being a high intensity fire, that dense green vegetation – including both the understory and root systems of the Douglas fir forests – has been burnt away, weakening the upper layer of the landscape. Vegetation typically holds soil in place on slopes with their root systems, and burning that vegetation takes away what is essentially an underground safety net. This means landslides and debris slides are a major concern for the areas affected by the Holiday Farm Fire.
“A lot of slopes have unstable soils to begin with. Take the vegetation off it, and you’ll get potential landslides and earth movement,” Leavell said.
As many homes are built on or at the base of these tall, steep slopes that were baked by the fire’s intensity, any slides could be hazardous. Additionally, the McKenzie Highway and most other roads in the region are carved along the steep topography of the area, meaning a single slide could cut off transportation for remote residents of the McKenzie Valley. The chances of a slide occurring are heightened this time of year in Oregon, as much of the cascade ranges receive heavy rain and snowfall, all of which could loosen the already damaged soil and cause it to slide down hillslopes.
Another consequence of a major landslide is impact of sediment loads and debris to the McKenzie River. This could do a lot of damage, as the river is squeezed into the tight valley floor and bordered by highway and houses. The addition of a large dirt and debris jam could create dam-like effects including sediment build-up, the pooling of water in the river, and subsequent flood flows if/when that debris jam breaks in the future.
“I just hope that doesn’t happen… a lot of effort being put into preventing that from happening,” Leavell said.
Much of the work to control erosion is being undertaken by the Pure Water Partnership, a collaborative effort between multiple organizations including the Eugene Water and Electric Board (EWEB), McKenzie Watershed Council, Upper Willamette Soil & Water Conservation District, and others. They have installed numerous erosion control devices throughout the valley such as sediment fences, log barriers, check dams, and erosion blankets in hopes of controlling any debris flow. Most of these devices aim to protect houses, the river, and its tributaries.
The River
The McKenzie River is not only a source of drinking water for hundreds of thousands of people in its watershed, but it’s also a primary tourist attraction due to its beauty and healthy salmonid fisheries. Because the health of the river influences public safety and the livelihoods of the surrounding communities, effort and resources were applied to protect it immediately following the fire.
“There is significant threat from debris, asbestos, burnt plastics, and hazardous wastes left right on the river banks,” said the Executive Director of the McKenzie Watershed Council, Jared Weybright, “that’s a concern for immediate impacts on water quality”.
Immediately after the fire was extinguished, EWEB pulled away most hazardous debris from the rivers floodplain, and the McKenzie Watershed Council and other members of the Pure Water Partnership built sediment control devices on the banks to decrease runoff of heavy metals and other chemicals into the river.
EWEB has enhanced its usual monitoring of water quality in the McKenzie watershed, and has published the report of its findings comparing the chemical composition of the water post-fire to pre-fire conditions and EPA standards. Where EPA standards are available, no chemicals or nutrients were found to be within hazardous ranges in the McKenzie watershed as of December.
Though drinking water does not seem to have been seriously impacted, there is concern for the future health of the river ecosystem and its riparian areas. Similarly to the forested slopes surrounding the McKenzie, the shrubby riparian habitats that border the river were completely burned away along many stretches of river.
Riparian areas are characterized by their distinct hydrophilic plant communities which are very different from vegetation of upland forests, and thus are an interface between terrestrial and aquatic ecosystems. These shrubby areas provide many benefits to their environments, but two important services are that they act as a filter of erosion running off upland areas before it enters a waterway, and they also provide habitats for many insects which makeup a large portion of fish diets. Now that much riparian habitat has been burned, the McKenzie is left even more vulnerable to future sedimentation and other risks that could negatively impact river quality.
The McKenzie Watershed Council is working with hundreds of landowners to gain access to privately owned land in order to plan riparian planting and long-term restoration.
“We’ve identified 80 sites we’d like to see replanted this year… we’re looking at riparian areas mostly along main stem McKenzie,” said Weybright.
Weybright has credited most of the Council’s ability for fast-acting restoration planning to the Pure Water Partnership, which existed before the Holiday Farm Fire and already involved collaboration with organizations and landowners. This pre-existing relationship framework has benefited restoration planning by allowing the Council to quickly communicate and reach agreements with landowners who have sensitive habitats on their properties that were damaged in the fire.
The long-term restoration of these important strips of habitat along the river will be complex and involve intense effort. Not only will planting of native riparian species need to occur, such as alders (genus Alnus), salmonberry (Rubus spectabilis), willows (genus Salix), and sedges, but later revisits to restoration sites will be required to remove invasive species that may have moved into the disturbed area and monitor survival of the planted vegetation.
The McKenzie Watershed Council and its partners hope to replant 80-100 acres of riparian area across private properties along the river, which will take significant time as well as funding from local, state, and private groups. This is all worth it though, said Weybright, as restoring riparian areas will be a “building block to build back natural functions of the ecosystem.”
The Fish
Similar to other regions in the Pacific Northwest, Oregonians hold a special place in their hearts for salmonids – the group of fish including salmon, trout, and steelhead. The McKenzie River Valley is no different, as the river is home to healthy populations of Chinook salmon, winter steelhead, and resident rainbow and coastal cutthroat trout.
There are dozens of river and fishing-based companies built along the McKenzie, including rafting and kayak outfits, fishing guides and gear shops, and fishing lodges. Not only is there typically a continuous stream of tourist into the area for the year-round fishing opportunities, but people who live along McKenzie River also have a long history of enjoying the aquatic resources.
The McKenzie Flyfishers group was founded in 1964 and has worked for decades to increase knowledge of flyfishing, provide a community and forum for local fisherpeople, and enhance fisheries of the McKenzie River.
Members of the group commonly participate in fish surveys to monitor fish abundances and spawning habitat, work with partners to remove dams and other obstacles to fish passage, and are involved in programs such as SalmonWatch and Project Healing Waters.
“We would have been usually really active this time of year,” said David Thomas, a board member and former president of the group. But not this year. “We’re blocked from doing surveys of fisheries due to the need for cleanup before there’s serious reconstruction [of fish and their habitat].”
The Holiday Farm Fire decimated the communities and landscape of the river valley, and undoubtedly had concerning impacts on riverbank stability and water quality, but there may be one bright spot in the aftermath’s dark reality. When asked about how salmonid populations may be affected by the fire, Weybright said, “It’s a really complicated question… there’s going to be benefits and impacts.”
Impacts to the fisheries are related to factors that are negative to overall river ecosystem health such as increased nutrient loads and sedimentation, which can settle onto fish nests (called redds) and suffocate eggs.
But there’s a bright side. “Salmon thrive on disturbance… large wood is needed for habitat,” Weybright said.
Salmon do require complex habitat, including both fast and slow river stretches, a mix of pool and riffle habitats, and protective cover which large downed trees along a riverbank provide. The inputs of damaged trees from the fire and subsequent debris slides may actually have short- and long-term benefits to salmon and trout of the McKenzie River.
The Hatcheries
But while fish habitat may actually be enhanced as a result of the Holiday Farm Fire, Thomas has seen fire damage to the fish hatcheries built along the river, and is worried about the consequences.
The intake channels that have supplied the McKenzie Hatchery with water from the river for around a century are in need of major repairs after the Holiday Farm Fire. They are currently non-functioning.
“Consequences of that mean they can’t raise fish, because salmon do not do well out of water,” Thomas said.
In order to continue bolstering the McKenzie River’s salmon populations to enhance recreational fishing and support fishing license sales, the Oregon Department of Fish & Wildlife is now rearing and releasing salmon from the Leaburg Hatchery, which is also located on the river but escaped fire damage.
This may be good for the return of anglers to the area and for ODFW revenue, but there’s a major problem – the Leaburg Hatchery was not built for, and does not have approval to be, a salmon hatchery. This is not just an issue with governmental red tape and paperwork, but rather an issue of construction.
Salmon return “home” to where they hatched from their eggs at the end of their lifecycle to spawn. All hatcheries built for salmon rearing and release have a sort of man-made waterfall in the hatchery where the adult salmon will swim to when they are at the end of their lives and ready to spawn. Because the Leaburg Hatchery was not built for salmon rearing, it doesn’t have the ability to accept and take in returning adult fish.
This is potentially disastrous for the wild populations of salmon that are native to the McKenzie. When the hatchery-reared adult salmon return to the McKenzie and attempt to enter their birthplace, they will be unable to do so, and simply continue up river. There they will encounter their native counterparts that are similar to them in appearance, but have much higher survivability traits in the wild, including lower aggression rates, the innate ability to forage for wild foods, and more success at “homing” into their spawning grounds at the end of their lifecycle.
“So hatchery fish are going up to native spawning grounds. That means there’s genetic mixing, which is damaging to the wild fish,” Thomas said.
Clearing the Path Forward
Though the effects of wildfire on the environment are often complex and appear devastating, the people of the communities affected by the Holiday Farm Fire are now looking at their landscape with a sense of hope. While the future holds many uncertainties, one thing is certain; the forests will come back. The water of the McKenzie River will clear of sediment and ash will be washed away. The landscape will, in time, undoubtedly prevail and return to its former beauty.
There is also hope in partnerships. Numerous organizations, dozens of employees, and hundreds of volunteers will be helping with the environmental clean-up in the aftermath of this historic wildfire. Both existing and future partnerships between organizations and landowners will be key to restoring the health of the river and riparian habitats.
Perseverance and patience will be needed moving forward, and together, the communities and ecosystems of the McKenzie River Valley will slowly regrow.
Tune in tomorrow for Part 3 of this series.
If you would like to learn more about the Holiday Farm Fire or make a donation to organizations committed to rebuilding the affected communities, you can visit the following organization websites:
https://www.mckenzierebuilds.org/
https://www.cascaderelief.org/
By Lauren Zatkos
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