As summer approaches and temperatures heat up in the PNW, Portland residents are beginning to enjoy the long days and sunny, rain-less weather. While some are having fun in the sun, many people still remember Oregon's historic wildfires in September 2020, which had devastating effects on our people and environment.
Chauncey Anderson, a Hydrologist and Water Quality Specialist for the USGS Oregon Water Science Center, and his colleagues recognized the disastrous impacts of the wildfires on Oregon's rivers and drought-stressed ecosystems. Their paper, "A call for strategic water-quality monitoring to advance assessment and prediction of wildfire impacts on water supplies," discusses the critical factors that scientists , water resource managers, and government agencies should consider when studying water quality after catastrophic wildfires and preparing and mitigating against impacts to communities' water supplies.
Chauncey joins us to chat about this team's motivations to study post-wildfire water-quality monitoring, why this research is important, key points the general public should take away from this research, and more.
What motivated you and your colleagues to study this topic?
Our study grew out of a common set of problems being experienced nationally at about the same time, and initial grass-roots efforts among USGS hydrologists in Oregon and elsewhere to share notes and learn from each other. The extraordinary wildfires in September of 2020 affected a large proportion of Oregon's Cascades rivers that had been previously thought to be too climactically-moist to be susceptible to such widespread catastrophic wildfires. The combined effect of these fires was to threaten drinking water sources for about one-quarter of Oregon's population. and potentially to hard already drought-stressed aquatic ecosystems. Around the same time, numerous other wildfires across the west occurred, with similar local effects. Together with our colleagues nationally, we realized that he had common concerns about the resulting water quality as well as needs to predict ecosystem responses or assist restoration planning. Our of this we developed a larger national study about wildfires, including their effects on water quality and how to measure them, from which the publication by Murphy et al, is one of the early outcomes.
What was your favorite part of the research process?
Becoming better acquainted with our colleagues in other USGS Centers including learning more about the important work that each is doing, and how we could potentially do things better ourselves. Included in that process, we:
- Discussed and settled on several common, critical questions regarding wildfires, their effects on water quality, and the outcomes that we could target, that were consistent across our multiple study areas
- Designed and implemented a study that is consistent across the different climatological, physical, and hydrologic regimes represented by our various study areas
- Learned from each other about how best to handle certain real-world challenges to studying water quality resulting from wildfires across a range of conditions
I was also happy to be able to mentor several younger researchers that had recently joined our Center and / or were starting to take on new responsibilities. This included all parts of the study process, from designing the study and associated sampling, the practical aspects of ordering supplies and preparing for the field work and data collection, and the actual field sampling in these newly burned areas that presented new types of problem solving.
A lesson I've learned over the years is that there's no substitute for being on the ground, and this study reinforced to us all the value of getting out to our wildfire study sites to see how they were affected by the fires, how they responded hydrologically, and how their watersheds have been recovering over time. The learning from such field work is incalculable, yet highly valuable.
Why is this research important? What are the possible real-world applications? How can government agencies use this information?
In an era of confronting the realities of climate change, we as a global society are just now starting to see the impacts that may be coming at us, and to learn what types of information we'll need in the future to plan for and respond to such impacts. Wildfires and their effects on wildland and aquatic ecosystems are expected to increase in scope and severity, and we need to learn what to expect, how to mitigate it, and how to quantify and learn from it. This study will help us and others be responsive to future wildfires in consistent and educational manners, and hopefully provide a template for other areas experiencing similar problems as we did in Fall 2020. Government agencies can use this information for planning and budgeting purposes, for reducing risk, and for prioritizing responses to wildfires that might be induced by climate change, land use management, and water policies. Examples include the optimal criteria that we listed (Section 3.1, and Figure 1) that would strengthen assessment and prediction of post-wildfire water quality.
Water are the potential challenges to implementing this research into real-world applications?
Funding is always a big challenge; this study leveraged numerous other funding sources and capitalized on ongoing studies where possible, potentially providing a template for ways to study future fires where water quality concerns are important.
Many places are still data-poor under existing, baseline conditions. We identified that it's most helpful to have places with some existing data prior to wildfires that we can use for comparison with post-fire conditions. A challenge is to find ways to increase data collection in places across the country that could be susceptible to wildfire, or where the risk of substantial negative impacts to wildfires might be large.
Our findings are quite general, but local responses and conditions such as climate patterns can dictate critical differences from site to site. For example, some of our study areas, including those in Oregon, may be on a longer time frame (3-4 years?) before we see major responses whereas other places can get extreme responses on much shorter timescales. In New Mexico, where the wildfires immediately preceded the region's summer monsoon season, the affected watershed didn't have much time to stabilize after the fires and the result has included much higher sediment erosion and mudflows than in many other locations. Such local differences underscore the need to assess specific fire's potential hazards and respond accordingly, and local context may require different monitoring responses.
What will you and your colleagues do next to build on this work?
We are now in the middle of data collection described in the study, and soon will be working to publish the data and the study's findings regarding post-wildfire water quality, how long the effects are likely to last, what the downstream risks might be, and so on.
As part of the national study, the USGS has a team that concurrently is working on developing predictive models to better anticipate the effects of wildfire, including under what conditions such things as debris flows, landslides, harmful algal blooms, threats to drinking water, or other hazards might occur.
Why is this research important for the general public to know? What key details or takeaways should they keep in mind?
The general public is rightly concerned and alarmed as they see reports of wildfires growing in scale, duration, and intensity, and as they consider the various hazards such as wildfires represent. This study is useful for the public to recognize that the Federal Government and associated collaborators are attempting to address these unprecedented fires, and to learn from them to mitigate future hazards, or to provide information when the hazards develop.
Increasingly, many members of the public have had their own interactions with forest fires, from direct losses to evacuation orders to the unhealthy and unsavory aspects of smoke (and how days). Each person's story, or accumulated stories, adds to their interpretation of what they see from agencies and others that are responding to the fires. What I hope people might recognize in this work and our larger study is the emphasis and urgency from scientists and land management agencies to scale up research and understanding of fire responses in orders to try to minimize future damage and/or continue to learn from the fires about how to protect aquatic systems.