Contaminants from wildfires can create long term water quality concerns in areas far from the fire-impacted zones as drifting smoke plumes and rainfall runoff challenge standard water filtration techniques.
A recently published analysis of 23 studies across 28 watersheds determined that the concentrations of numerous pollutants in waterways experienced significant increases for five years after a wildfire burns. Researchers found that the presence of heavy metals and other toxic chemical compounds in affected bodies of water was up to 66,000-fold above environmental standards.
“Most wildfires leave behind a barren, blackened landscape, and within this changed environment, important impacts can leave their mark,” the researchers said in a piece published in The Conversation. “Streams, rivers and water reservoirs receive a sudden pulse of ash, sediment and fire-suppressant chemicals washed off the land. For communities that depend on those waters for drinking water, wildfires can quickly become a long-term water-quality problem.”
The extent of water contamination depended on numerous factors, including burn severity, the types of soil and vegetation present, and how close the burned area was to nearby streams and reservoirs. But, the researchers also found that water contamination can extend far past where a fire burned. They looked data from watersheds in Canada, the US, Australia and Portugal.
Most of the toxic chemicals produced during wildfires are transported to nearby waterways during runoff from rain and other precipitation, but the study determined that smoke plumes also transport compounds to other water sources distant from the fire’s perimeter. One of the studies analyzed by researchers said certain toxic chemicals were transported 54 miles from a wildfire, while another study said waterways over 400 miles away could be contaminated by smoke plumes.
“Conventional treatments, such as coagulation and flocculation, sedimentation, rapid sand filtration, and, occasionally, granular activated carbon adsorption, are not designed to handle simultaneous spikes in turbidity, organic matter, trace metals, and other wildfire-derived contaminants, resulting in health risks to the inhabitants.”
“Unlike direct runoff from burned areas, the combined mechanism of atmospheric deposition followed by hydrological transport in unburned watersheds remains poorly quantified,” the researchers said in the analysis. “Despite their long-term persistence and toxicity, post-wildfire concentration variations of trace metals, PAHs, POPs, and WFFCs have not been studied extensively, especially concerning their persistence in sediments and possible remobilization, indicating that further research is required to understand their long-term effects on surface water bodies and aquatic environments.”
Dr Xinyan Huang, Assoc Prof Hong Kong Polytechnic University
This award honours Associate Editors who have demonstrated sustained excellence in their responsiveness, thoroughness, and timeliness.
Dr Huang has served as an Associate Editor of the International Journal of Wildland Fire (IJWF) since 2021. He is an Associate Professor at the Dept of Building Environment and Energy Engineering, Hong Kong Polytechnic University. He is the Deputy Director of the Research Centre for Smart Urban Resilience and Firefighting. He received his PhD from Imperial College London.
CSIRO Publishing produces IJWF on behalf of the International Association of Wildland Fire.
Canada’s long-term pledge to build up its aerial firefighting resources has begun with the lease of 12 aircraft that will be shared nationally for the 2026 wildfire season.
As reported in March, Canada has put aside $316.7 million over the next five years for the Canadian Interagency Forest Fire Centre (CIFFC) to manage a national fleet of aerial firefighting resources for all provinces and territories based on current and urgent needs.
The fleet will increase Canadian surge capacity during periods of elevated wildfire activity, support rapid deployment of resources, address provincial and territorial gaps, and enhance Canada’s wildfire resilience.
This summer, Canadian wildfire agencies will have access to the following resources: • Four Dash 8-400 AT (Land-based Airtankers), one TBM960AA (Birddog), and two Forward Attack Tanker Bases through Conair Group Inc. • Three Airbus AS332 L & L1 (Heavy rotary wing helicopters) through Coldstream Helicopters Ltd. • Two Sikorsky S-92A (Heavy rotary wing helicopters) through VIH Helicopters.
These aerial assets will be strategically propositioned in Canada based on provincial and territorial need, fire activity, and preparedness level. However, aircraft can be relocated at any time to address the current situation. The operational contract period runs May 1 to September 27, 2026. All three suppliers are based in British Columbia.
CIFFC will coordinate the aerial assets on behalf of member agencies, said Kelsey Winter, Executive Director of CIFFC. “A pan-Canadian response that assists our provincial and territorial partners in reducing the increasing impact of wildfires is paramount. Together, we are building a more wildfire resilient future for our country.”
Conair proudly claims it manufactures, owns and operates the world’s largest fleet of fixed-wing aerial firefighting aircraft.
“For the first time, Canada has its own national fleet to bolster provincial and territorial firefighting capacity.” said Chris Niemann, President and CEO of Conair. “We are proud to be part of this moment in history, committed to supporting firefighters across the country using our aircraft, made in Canada and operated in Canada, supported by hundreds of Conair aerospace professionals.”
Conair promotes the Dash 8-400 as a proven platform, with more than two dozen operating worldwide. It delivers large retardant drops to slow fire progression, working alongside water scoopers to cool flames. It also operates from shorter runways closer to fire prone areas and can reload in seven minutes. Conair makes four new Dash 8-400 airtankers every year with a capacity to increase production if called upon.
Extinction has always been a risk on Santa Rosa Island. Researchers have hailed the California island as having the most prolific aleontological record of extinct species such as pygmy mammoth, flightless sea duck, vampire bat and giant deer mouse.
The environment is now home to animals and plants found nowhere else on Earth, earning its nickname “Galapagos of North America.” A human-caused wildfire now threatens those unique animals and plants with extinction, according to on-site fire officials.
Over a third of the island has burned since a wildfire started on May 15, which burned 18,379 acres and was at 87% containment as of Sunday morning, according to Channel Islands National Park officials. Santa Rosa is one of the five Channel Islands.
Credit: NASA
There is relatively less fire on the Channel Islands than on the mainland because ignition sources are much less common there and the foggy maritime climate generally limits fire spread.
“Several island taxa have relaxed fire-adapted traits such as serotiny and seed germination characteristics,” officials said on the park’s website. “Records from both Santa Cruz and Santa Rosa show that fire frequencies increased over the last 5,000 years and reached their peaks during the historic period, approximately the last 200 years.”
A major concern of officials was the status of the island’s Torrey Pines, the rarest pine tree in North America. The trees once dominated the island’s “Cloud Forest” of plants that harvested water from the heavy fog that rolled across the island and condensed on leaves and twigs. Although small pockets of the trees did burn with higher intensity, recent drone imagery showed that groves of Torrey Pines still exist and remain largely intact.
“The National Park Service has special firefighters, known as fire effects crews, that will go to this area, taking measurements such as specific fire severity calculations and observations,” officials said in a recent update. “This is not just a single snapshot but will be part of long-term monitoring of effects to better understand fire in this ecosystem.”
Credit: Inciweb
Officials were already working to restore the island’s native ecosystem before the fire started. Grazing that started during European colonization of the area in the mid-1800s eliminated over 75% of the entire island’s native vegetation, park officials said.
While many native plants have since been reestablished throughout the island, the Cloud Forest hasn’t recovered. Grazing animals stripped the soil down to bedrock and severely increased soil erosion, causing trees to topple. Crews responding to the fire are reportedly aware of this ongoing issue and are working with biologists, archeologists and cultural specialists to minimize ground disturbance and soil compaction.
“This work will reduce soil erosion potential by spreading and slowing water flow and increasing soil cover, discouraging undesired access, and reducing visual impacts of fire suppression activities,” crews said.
The wildfire’s effect on the vulnerable environment’s recovery won’t be fully understood until researchers analyze the landscape after the fire is 100% contained.
Germany is a little smaller than California but has almost twice as many people, about 84 million. Though the country is densely populated and industrialized in large areas, about 30 per cent is defined as forest land – half the trees are conifers – and 50 per cent of Germany’s land mass is used for agriculture. There is a lot of vegetation.
A first glance at available data shows no real wildfire problem in Germany, but the country faces more wildfires and an increase in fire intensity. In addition, wildfires on military ranges with unexploded explosive ordinance (UXO) contamination from two world wars and the training areas used during the Cold War create significant problems.
Fires on UXO-contaminated areas are difficult to fight considering that ground forces must stay away 1000 meters from the fire because of the imminent risk of exploding UXOs; the use of aircraft is hampered by the high altitude at which they must fly, for the same reason.
The long-lasting drought from 2018 to today – which resulted 2022 being the first real fire season in Germany with several large campaign fires – has led to predictions that the fire regime and fire behavior from the Mediterranean areas will extend slowly but steadily north in the next 20 to 30 years or even sooner.
Wildfires on military ranges with unexploded explosive ordinance (UXO) contamination from two world wars and the training areas used during the Cold War create significant problems. Photo: Jan Südmersen, @fire and Detlev Maushake, WAldbrandteam.
In Germany, fire suppression is generally provided by municipal fire departments. Beside the armed forces fire service there are no federal- or state-owned fire resources due to Germany being decentralized by the allies after the Second World War.
Most fire departments are volunteer – there are about one million volunteer firefighters and just 30,000 paid firefighters in Germany. There are also 330,000 members of the Jugendfeuerwehr, fire explorers for young people from age 10 to 16.
Wildland fire tactics rely heavily on the use of fire engines and tenders, of which there are 40,000 in Germany; specialized brush trucks are still rare and not standardized. The use of handlines exceeding the capability of water shuttle operations is one of the main reasons firefighters lose a lot of battles.
A new training curriculum was put together by a working group over four years that offers guidance in the use of LACES (Lookouts, Anchor Points, Communication, Escape Routes, and Safety Zones) and safe tactics as a base for the general firefighter in Germany.
Regarding air operations, there is only one fixed wing (a PZL 18 Dromader on seasonal contract in one county) and helicopters must be ordered from the army, police or contractors – if they are available, and even if they are, there may be a two-to-six-hour response time. The same applies to heavy equipment such as dozers, which are not commonly used or even considered by incident commanders.
The concept of an autonomous working handcrew is not known to the German fire service so far, because there are simply none (yet). Although many fire departments purchase hand tools such as Pulaskis and combination tools like the Gorgui, members are not sufficiently trained to cut handlines for a prolonged time, and there is no utilization of tactical fire.
Volunteer handcrews?
Predicting the need for specialized units such as handcrews, the non-profit @fire was founded in 2002, followed by Waldbrandteam in 2015; both are non-governmental, independent organizations. The founding teams collected a lot of experience and knowledge from internships with several handcrews and fire services in the United States, Canada and southern Europe.
Coming from outside the traditional fire services (even though the majority of the members in both NGOs are firefighters too), we were mostly considered rogues in the beginning; this did not stop us from continuous networking and providing wildland fire training for hundreds of fire departments (there was no specialized wildland fire training available until 2020), which resulted in more acceptance and integration. Both organizations built an international network, trained members according to international standards such as those of the US-based National Wildfire Coordinating Group, and sent them on internships to gain experience – without any federal funding and by 100 per cent volunteering. Both NGOs have the status of fully accepted civil protection measures by German law.
During the 2022 fire season our NGO-handcrews were requested for several deployments, which clearly pointed out the need for specialized handcrews in Germany. Feedback from the fire departments working with the NGOs on the 2022 fires was positive given the fact that the work was in conjunction with local resources and that the experience was also for training and an exchange of experiences.
Capacity building is beginning
In the aftermath of the 2022 fires, things started to shift. Being Germans, the focus was on purchasing specialized fire trucks, a discussion that resulted in a new variety of brush fire trucks based on the French medium forest fire tanker trucks, but again with no nationwide standardization.
Finally, post-2022, some fire departments started to build specialized units similar to handcrews, following the example of the NGOs. Being asked for advice and training for these units, Waldbrandteam and @fire developed and published a guideline for handcrew capacity building https://www. at-fire.de/veroeffentlichung/fachempfehlung-loeschmannschaften/ (Fachempfehlung Löschmannschaften).
Applying National Wildfire Coordinating Group standards adapted to the German and European setting, we defined two types of handcrews: Type A and B.
Type A handcrews mainly support engine crews with long-distance hoselays and mop-up operations. The idea is that these crews are widespread regional teams organized and founded at the county level with limited training and equipment, so that they are easy to build and to maintain.
Type B handcrews are essentially copies of National Wildfire Coordinating Group Type II Initial Attack crews made for working autonomously, nationwide and even internationally. This requires:
• Adapting fitness standards (pack test, work capacity test)
• Language capabilities (everybody must speak English)
• (Online) NWCG courses: NWCG S-100/130/190/270/ L-180, S-211 and S-212
• Field days or even weeks depending on the level of expertise and training to harden the knowledge
• Personal gear including a line pack
• International deployment preparedness (vaccines, cultural awareness, safety and security)
• Building a tool and logistics cache
• Being self-sufficient for at least 24 hours
• Training with their own tools, but also knowing tactics and tools in Europe
Both @fire and Waldbrandteam are in the process of establishing Type B handcrews.
Type A handcrews mainly support engine crews with long-distance hoselays and mop-up operations. Photo: Jan Südmersen, @fire and Detlev Maushake, WAldbrandteam.
What’s next?
Type A handcrews: There is a growing number of fire departments interested in building Type As. The NGOs, @fire and Waldbrandteam, are building a network, mentoring, and training these new crews. Both organizations are also supporting state fire academies, forestry units and helicopter companies in establishing specialized training to work with the handcrews.
Type B handcrews: The NGOs can deploy their own Type B crew, or a combined crew from both @fire and Waldbrandteam. There is some discussion about
incorporating and cooperating with qualified personnel from larger fire departments and applying to become a certified module of the European Union Civil Protection Mechanism.
Besides funding, the biggest challenge in building the handcrews is to provide (volunteer) members with firsthand training, and then to gain experience on the fireline. It is very difficult to explain the idea and goals plus the structure of the NGO crews to governmental agencies abroad. Often the combination of the terms NGO and volunteers lead to a break in communications and the misunderstanding that that there is a lack of professionalism due to this combination.
A big step forward was the signing of a memorandum of understanding with CalFire in 2024; @fire was given the opportunity to attend classes and send some members to internship with various handcrews.
At this point, the NGOs are reaching out to the international wildland fire community looking for more possibilities for training and internships.
A model for other nations?
Seeing the numbers in Germany you might think that there is a deep conflict between paid and volunteer firefighters, because if you have enough volunteers, you just don’t need paid firefighters.
Honestly, we can’t claim that conflict doesn’t exist. But, beside our passion for wildland fire fighting, we both are members of paid and volunteer fire departments and from our experience, we regularly see the synergy of those systems working together. Not only are volunteer fire departments very successful at providing fire protection for most German communities, but there is also a large number of combined fire departments, where paid firefighters provide the initial response and volunteer firefighters provide manpower at bigger events and specialized units with backup for the full-time, career firefighters. It works!
Transferred to wildland fire
Beside using volunteers in supporting roles, volunteer handcrews – well trained (to the same standards!) and led by experienced crew captains – could be valuable assets in initial attacks and structure defence, especially in large-scale events or intense fire seasons where resources are stretched.
Volunteers are not a substitute for paid, full-time crews because of their limited availability and limited deployment length of 24 to 72 hours.
We are aware that there are many more points for or against this idea, so we invite you to open your mind and discuss it.
What would Ben Franklin (or, in Germany, Conrad Magirus) think of implementing volunteer handcrews to protect their communities?
Jan Südmersen is division chief for the City of Osnabrück Fire Department and the founder of @fire Germany.
Detlef Maushake is a captain with the City of Salzgitter Fire Department and the founder of Waldbrandteam. Maushake was the recipient of the 2019 IAWF Firebreak Award for Excellence in Wildfire Management.
Nebraska is still reeling from recent destructive wildfires and heading into what’s expected to be an active fire summer.
A new website launched by the University of Nebraska–Lincoln seeks to put the state’s long history of fire on full display, and in turn, help farmers, ranchers and land managers restore the state’s native grasslands.
Thehistoric Morrill Fire and other wildfires burned 821,000 acres across the state between March and April, by far the highest number of burned acres the state has seen in generations. Gov. Jim Pillen recently requested President Donald Trump to issue a major disaster declaration and subsequently unlock federal recovery funding in response to the fires.
The wildfires have been an unwelcome reminder for many that fire is a natural part of the state’s ecosystem. The Great Plains’ grasslands have long been fire-dependent, with frequent burns both benefiting native wildlife and destroying ever-encroaching invasive plants.
“Wildfire recovery unfolds over years, not months,” said Dirac Twidwell, rangeland ecologist at the university. “What we’ve built here is not just a map of fires — it’s a system that helps people understand recovery, anticipate change and respond with better information.”
The online hub was built using data from over 1,300 wildfires across the Great Plains since 1985, university officials said in a press release. The data allows people to view the specifics of historical fires, along with analyzing vegetation’s response to wildfire, and inform recovery decisions.
The data behind the platform draws from multiple national and research-backed sources, including the Rangeland Analysis Platform for vegetation data, the Monitoring Trends in Burn Severity database for historical wildfire perimeters and the National Interagency Fire Center for recent fire data.
“That long-term record lets us see how grasslands actually recover — across different weather patterns, management decisions and landscapes — and that perspective is critical for making sound decisions today,” Twidwell said in the press release.
For example, the critically important Crescent Lake National Wildlife Refuge, which is located in one of the world’s most important intact prairies, was largely burned in the Morrill Fire. The university’s map offers hope for the Refuge in the near future, showing numerous other fires had burned there over the past decades.
Pilots are being pressured to fly into potentially dangerous fire scenarios or where aircraft would provide little benefit, despite worsening aerial firefighting safety risks, according to a newly released survey conducted by the Australian Transport Safety Bureau.
The federal agency conducted interviews with nine firefighting aircraft operators and 11 fire agency representatives from around Australia to understand the current safety risks in the field. It notes that since 2016, the ATSB has commenced 17 investigations involving aerial firefighting aircraft with incidents steadily increasing.
“Additionally, the ATSB has received anecdotal reports from aerial firefighting pilots and operators concerned about the way activities are coordinated and unsafe tasking. These reports also indicated that many do not want to report occurrences to the ATSB as it may affect their potential to win contracts with firefighting agencies,” the report notes.
The results showed that how safe the industry feels largely depends on who you ask, and both the safety and occupational risks they face.
The majority of aerial firefighting operators said they didn’t feel that agencies valued their safety and had a negative “safety culture.” This contrasted with the answers given by fire agency representatives, who claimed safety had “always been very much at the forefront” of their operations.
“Interviewees perceived a lack of understanding of aviation safety and risk management among senior fire agency personnel across states and territories,” the surveyors said. “Interviewees’ understanding of who was accountable for aerial firefighting safety varied, indicating a lack of clarity on this issue.”
A similar disparity was found in how operators and agency representatives viewed the pressure placed on pilots to fly. While every interviewee acknowledged there was some pressure to fly, they differed on where that pressure came from.
Firefighting operators largely blamed their pressure to fly on agency personnel, describing both overt pressure and implicit pressure like being asked to “take a look” at flight conditions. The responses from agency representatives said the exact opposite, claiming the agencies placed no pressure on pilots and instead blamed either more senior agency personnel or public and political pressure.
“Interviewees believed this was because aircraft, especially LATs, are a very powerful visual representation of agencies’ and governments’ response to bushfires,” the surveyors said. “Three of these interviewees specifically mentioned public or political pressure to fly relating to LATs.”
Numerous interviewees said operators would feel safer if fire agencies enhanced their management and developed a just, learning, reporting, informed and flexible safety culture. A shared desire for standardisation and formilization of policies and procedures was also present in the responses.
“This desire was expressed in relation to aircraft coordination, communication, training, pilot performance, and the identification of risk and monitoring of changing conditions,” Bureau Chief Commissioner Angus Mitchell said in a press release regarding the report.
The survey is part of an ongoing ATSB safety study into Australia’s growing aerial firefighting sector. While findings and recommendations will be saved for the final report, this survey report identified 18 key safety themes.
Around 500 aircraft provided by over 150 operators are used in aerial firefighting operations across Australia.
An Air-Crane helicopter drops muddy water on one of the fires in the East Gippsland region of Victoria, December 30, 2019. Photo by Ned Dawson for Victoria State Government.
The United States’ Natural Resources Conservation Service on Thursday issued a dire forecast for Western states, ahead of what’s expected to be a very active wildfire season.
The Service, overseen by the Department of Agriculture, said many of the states’ rivers are expected to have extremely low streamflows for the spring and summer seasons.
“Many of the rivers are likely to experience well-below median streamflows, which may rival the lowest flows on record for the region,” the Service said in the Department’s most recent Water and Climate Update. “Water shortages are anticipated in many locations, especially for entities that rely on surface streamflow water, without the benefit of having access to stored reservoir water.”
Service officials said the low streamflows will have major impacts on wildlife, recreation, city municipalities, power generation and agriculture.
Credit: USDA
The low streamflows were blamed primarily on record-low snowpack during the winter months, which also melted weeks earlier than normal. The “unprecedented” snowpack levels were the lowest in 40 years, and researchers said the only way extreme fire chances could be reduced was through a “major switch” in circulation patterns. So far, there’s nothing in season forecasts or weather models that indicate such a switch is on its way.
“Unfortunately, this year in the West and southern tier, it has been very dry and very warm,” Physical Sciences Laboratory research meteorologist Andrew Hoell recently said. “We’re talking about some historically warm conditions and at the same time below average precipitation. That sets up the land surface to be able to burn.”
Hoell was the lead author of a recent study that found the “La Niña” and “El Niño” phases of a fluctuating water temperature climate pattern called the El Niño-Southern Oscillation act as accurate predictors of wildfire severity up to a year in advance. The pattern entered its La Niña phase last fall, and was followed by the historic snow drought and early spring heat wave, which created drier and more flammable fuels.
Wildfire Camp will display around 20 companies and other organizations on early detection, prevention and suppression of wildfires. While small in relation to the rest of the trade fair, the arrival of Wildfire Camp signals a growing acceptance of wildland fire as an essential part of overall fire management planning and resourcing in Europe.
The Interschutz fire and rescue services trade fair is huge – around 1750 exhibitors from 55 countries will be in Hannover from 1-6 June 2026. The exhibition space fill nine halls plus outdoor displays and in the past has attracted up to 150,000 visitors.
Interschutz. Photo: Rainer Jensen
Wildfire Camp is the work of four main players – Bosch Building Technologies, the European Forest Institute (EFI), @fire, and IMBOS e.V, bringing together science, emergency responders, and technology providers.
The International Association of Wildland Fire will host a stand in the Wildfire Camp that will also include CAL FIRE, the California Department of Forestry and Fire Protection, Airbus, Drager, Husqvarna, OroraTech, Vallfirest, Waterax and others.
“Driven by climate change, which is one of our key focus topics, we decided to launch this premiere,” says Thilo Horstmann, Head of INTERSCHUTZ at Deutsche Messe AG. “The camp is far more than a simple product showcase. It has been designed by recognized experts.”
The demonstrations area is divided into pre-and post-fire management, vehicle-based firefighting, aerial support, ground crews, and special operational options.
Reflecting the desire to not just promote hardware and other services, the Wildfire Camp has a strong emphasis on understanding wildfire in a European context and learning from international experts. In addition to the outdoor demos there is a program of expert presentations and panel discussions into operational strategies, early detection technologies, prevention measures by the European Forest Institute.
But scientists are still working to uncover how wildfire smoke affects other living beings, in both the short and long term. Researchers at Oregon State University took another step to uncover that mystery by studying one of the state’s most important agricultural commodities: cattle.
The researchers recently published their findings in theJournal of Animal Science, showing that wildfire smoke often causes invisible yet meaningful health issues in beef-on-dairy cattle, which contribute around $791.5 million annually to the state’s economy. The study analyzed 18 beef-on-dairy calves on a commercial dairy near Vale in 2022 and tracked their health before and after smoke from the Amelia Road fire affected local air quality for four days.
The calves did not develop any obvious diseases after the smoke exposure, but blood tests told a more subtle story, according to researchers Juliana Ranches and Jenifer Cruickshank.
“After smoke exposure, calves showed higher cortisol, a sign of acute stress,” the researchers said in a university press release. “They also showed changes in inflammatory markers, immunoglobulins and cytokines, indicating that smoke exposure activated immune and inflammatory responses even without severe outward illness.”
The immune and stress responses triggered by wildfire smoke are at risk of causing future health issues, such as increased susceptibility to secondary respiratory infections or reductions in growth or productivity, according to the study. The findings become more concerning due to their similarity to bovine respiratory disease symptoms, which makes potential wildfire smoke-caused symptoms even harder to diagnose.
The study’s findings show just how much wildfire smoke can act as an environmental stressor on cattle’s physiology and immune function, the researchers said. The “subclinical” effects are critical to informing ranchers’ future management and mitigation strategies for protecting their livestock.
