A double whammy: Wildfire debris pollutes drinking water

February 5, 2023 / activist360

(Photo credit: U.S. Department of Agriculture / CC BY 2.0) — *Credit: U.S. Department of Agriculture / CC BY 2.0*

Wildfires, which have intensified with climate change, litter the ground with debris that can contaminate drinking water supplies after a heavy rain.

By Alex Urquhart and Tanya Petach, Yale Climate Connections (CC BY-NC-ND 2.5)

The largest wildfire in New Mexico’s state history burned over 300,000 acres in the summer of 2022 and came within a mile of the town of Las Vegas. The flames ultimately spared the town of 13,000, but months later, ash and soot left by the Calf Canyon/Hermits Peak wildfire fouled drinking water there when monsoon rains blanketed the region, paradoxically slamming Las Vegas with both flooding and a municipal water shortage.

Four people drowned in flash floods, and residents were forced to erect sandbag barriers to protect their houses. Meanwhile, the inundation overwhelmed the town’s water filtration system with ash contamination, forcing mandatory restrictions to cut water consumption by about two-thirds. Swimming pools went empty, and restaurants resorted to disposable dishes and utensils to cut back on dishwashing.

In September, New Mexico spent $2 million to rapidly install a temporary pre-treatment system. It is still propping up the overstrained filtration system while the town applies for federal funds for a permanent water treatment facility that the mayor estimates could cost as much as $100–200 million.

Climate change is worsening wildfires

Around the world, more extreme wildfires have become a shocking signal that the effects of climate change are here. Wildfires are now more common and more destructive, making their damage more expensive.

Climate models have predicted this worsening trend for years and suggest it will continue as long spells of hot and dry weather become more common. In California, 12 of the 20 largest fires since 1932 occurred in the last five years. In the Mediterranean, the frequency of so-called “fire weather”—hot and dry weather that leads to large wildfires—is projected to increase by up to 30% by the end of the century.

Toxic runoff dirties drinking water

Although the dramatic violence of wildfires attracts intense media coverage, long-term impacts on water quality have gone largely unreported. The problem is alarming in the U.S. West, which has wrestled with regional water shortages for years. Researchers are finding that heavy rains in areas affected by wildfires can contaminate watersheds and overwhelm municipal drinking water systems. Municipalities must often pay astronomical costs to augment, repair, or replace entire water distribution systems. With risks growing, researchers say at-risk areas must plan ahead to act quickly and communicate clearly about water issues to fire-hit residents.

Wildfires lead to increased flooding and sediment erosion into rivers because a healthy forest is no longer there to slow stormwater runoff and increase water absorption. During storms, ash from the wildfire will be carried unchecked directly into streams, where it can easily flow to a municipal water intake and overwhelm treatment plants, leading to water shortages or even total failure of municipal water systems.

Following the Rocky and Wragg fires in California, researchers studying the affected watersheds recorded drastic increases in dissolved organic carbon, dissolved organic nitrogen and ammonium. It took over a year for these levels to return to normal.

When fires burn through developed areas, toxic runoff is created from the destruction of building materials, electronics, appliances, and vehicles. Rain transports these dangerous chemicals into groundwater, contaminating private wells and municipal systems. This can force months of boil water advisories, or even do not drink/do not boil orders, where drinking water must be brought in from other areas.

Even the water distribution system itself can become a source of contamination. Following the Tubbs Fire and the Camp Fire in California, both of which burned through developed areas, researchers found that municipal drinking water exceeded exposure limits for volatile organic compounds such as benzene. The source of this contamination may have been fire damage to plastic pipes and other synthetic components of the distribution system. With so many potential sources and causes of contamination, it is challenging for public officials to define an appropriate response. This has led to conflicting or variable recommendations in the aftermath of a fire, damaging public trust in official guidance.

Can we build fire-resilient water systems?

As wildfires worsen globally, water quality problems will affect millions of people who live in threatened watersheds. In addition to cutting planet-heating emissions, specific solutions are needed to protect public health and safety from the inevitable fires to come.

Researchers who studied the aftermath of the Tubbs and Camp Fire have called for standardized and streamlined water quality monitoring following wildfires. They recommend a “do not use” order following any wildfire that burns through developed areas. Other recommendations include updated building codes to limit the spread of contaminated water within damaged distribution systems.

Clear health and safety guidance in the aftermath of a fire is crucial. In the months following the Camp Fire, surveys of 233 households within the affected community showed 54% had some level of anxiety about water contamination, and 85% were seeking alternative water sources. The public needed clear recommendations about drinking water safety, including how to conduct at-home testing. Following a fire, clear and regular communication may be required for months or years, depending on the scope of contamination.

Municipalities may also identify standard operating procedures and fire response policies before disaster strikes. A new study examining the 2021 Marshall fire in Colorado outlined potential mitigation procedures that municipalities could implement, from emergency planning to post-fire flushing protocols.

“There are very simple straightforward actions that municipalities can take today to prevent wide-scale water distribution system contamination,” said Andrew Whelton, a lead author of the study. For example: “isolating your water distribution center into zones so that if one part of the system is damaged it doesn’t spread to the other parts of the system.”

Having a plan in place will reduce confusion and increase trust and efficiency in the wildfire response, recent research suggests. One vital consideration is the level of water contamination that constitutes acceptable or unacceptable health risks.

“There are certain conditions that would indicate that your water is lightly contaminated and you should not use it,” Whelton said. “The Marshall Fire case study identifies those conditions, and another study identifies conditions of contamination in private wells. Your water can be chemically contaminated after a fire, and you have to do testing to determine if it is safe or not.”

Understanding these thresholds will lend clarity and speed to post-fire decision-making. And with climate change accelerating, the need for standardized practices that will educate the public about water safety and ensure access to clean water will only grow.

Alex Urquhartis the research and modeling manager at Energy Innovation Policy and Technology LLC® and Tanya Petachis the Climate Science Fellow at the Aspen Global Change Institute. Both organizations are Yale Climate Connections content-sharing partners.

*This post was updated Feb. 3, 2023, to reflect the correct spelling of Andrew Whelton’s name.

Researchers warn Great Salt Lake’s retreat threatens crucial ecosystem, public health

January 8, 2023 / activist360

Great Salt Lake Desert, Utah, USA by Urvish Prajapati on Unsplash — *Great Salt Lake Desert, Utah by Urvish Prajapati on Unsplash*

“The lake’s ecosystem is not only on the edge of collapse. It is collapsing,” said one ecologist.

By Julia Conley, Common Dreams

Scientists are warning Utah officials that the Great Salt Lake is shrinking far faster than experts previously believed, and calling for a major reduction in water consumption across the American West in order to prevent the lake from disappearing in the next five years.

Researchers at Brigham Young University (BYU) led more than 30 scientists from 11 universities and advocacy groups in a report released this week showing that the lake is currently at 37% of its former volume, with its rapid retreat driven by the historic drought that’s continuing across the West.

Amid the climate crisis-fueled megadrought, the continued normal consumption of water in Utah and its neighboring states has led the Great Salt Lake to lose 40 billion gallons of water per year since 2020, reducing its surface level to 10 feet below what is considered the minimum safe level.

“Goodbye, Great Salt Lake,” tweeted the Environmental Defense Fund on Friday.

Goodbye, Great Salt Lake👋 Megadrought and mismanagement have cost the lake 73% of its water. Now experts are warning it could dry up in the next 5 years. And “Its disappearance could cause immense damage to Utah’s public health, environment, and economy”https://t.co/oecZ0qQ8C0
— EDF (@EnvDefenseFund) January 6, 2023

Scientists previously have warned that increased average temperatures in Utah—where it is now about 4°F warmer than it was in the early 1900s—are to blame for a 9% reduction in the amount of water flowing into the lake from streams.

The authors of the BYU study are calling on Utah officials to authorize water releases from the state’s reservoirs and cut water consumption by at least a third and as much as half to allow 2.5 million acre feet of water to reach the lake and prevent the collapse of its ecosystem as well as human exposure to dangerous sediments.

“This is a crisis,” BYU ecologist Ben Abbott, a lead author of the report, told The Washington Post. “The ecosystem is on life support, [and] we need to have this emergency intervention to make sure it doesn’t disappear.”

The shrinking of the Great Salt Lake has already begun creating a new ecosystem that is toxic for the shrimp and flies that make it their habitat, due to the lack of freshwater flowing in. That has endangered millions of birds that stop at the lake as they migrate each year.

The loss of the lake may also already be exposing about 2.5 million people to sediments containing mercury, arsenic, and other toxins.

“Nanoparticles of dust have potential to cause just as much harm if they come from dry lake bed as from a tailpipe or a smokestack,” Brian Moench, president of Utah Physicians for a Healthy Environment, told the Post. Last month, Moench’s group applauded as Republican Gov. Spencer Cox’s administration, under pressure from residents, walked back its position supporting a plan to allow a magnesium company to pump water from the Great Salt Lake.

Abbott called the rapid shrinking of the lake “honestly jaw-dropping.”

“The lake’s ecosystem is not only on the edge of collapse. It is collapsing,” Abbott told CNN. “The lake is mostly lakebed right now.”

What is a wetland? An ecologist explains

October 2, 2022 / activist360

By Jon Sweetman, The Conversation US CC BY-NC-ND 4.0)

Wetlands are areas of land that are covered by water, or have flooded or waterlogged soils. They can have water on them either permanently or for just part of the year.

Whether it’s year-round or seasonal, this period of water saturation produces hydric soils, which contain little or no oxygen. But this doesn’t mean that they are lifeless: Wetlands are full of unique water-loving plants and wildlife that have adapted to wet environments.

Wetlands can take many different forms, depending on the local climate, water conditions and land forms and features. For example, swamps are dominated by woody trees or shrubs. Marshes often have more grasslike plants, such as cattails and bulrushes. Bogs and fens are areas that accumulate peat – deposits of dead and partly decomposed plant materials that form organic-rich soil.

Trillions of dollars in ecological benefits

Wetlands are important environments for many reasons. They provide ecological services whose value has been estimated to be worth more than US$47 trillion per year.

For example, wetlands support very high levels of biodiversity. Scientists estimate that 40% of all species on Earth live or breed in wetlands.

Wetlands are critical homes or stopovers for many species of migratory birds. In the central U.S. and Canada, for example, wetlands in the so-called prairie pothole region on the Great Plains support up to three-quarters of North America’s breeding ducks.

The hunting and conservation group Ducks Unlimited works to conserve prairie pothole wetlands on North America’s Great Plains.

Along with providing important habitat for everything from microbes to frogs to waterfowl, wetlands also work to improve water quality. They can capture surface runoff from cities and farmlands and work as natural water filters, trapping excess nutrients that otherwise might create dead zones in lakes and bays. Wetlands can also help remove other pollutants and trap suspended sediments that cloud water bodies, which can kill aquatic plants and animals.

Because wetlands are often in low-lying areas of the landscape, they can store and slowly release surface water. Wetlands can be extremely important for reducing the impacts of flooding. In some places, water entering wetlands can also recharge groundwater aquifers that are important for irrigation and drinking water.

Wetlands also act as important carbon sinks. As wetland plants grow, they remove carbon dioxide from the atmosphere. They they die, sink to the bottom of the wetland and decompose very slowly.

Over time, the carbon they contain accumulates in wetland soils, where it can be stored for hundreds of years. Conserving and restoring wetlands is an important strategy for regulating greenhouse gases and mitigating the impacts of climate change.

Resources at risk

Despite the many valuable services they provide, wetlands are constantly being destroyed by draining them or filling them in, mainly for farming and development. Since 1970, the planet has lost 35% of its wetlands, a rate three times faster than the loss of forests.

Destruction and degradation of wetlands has led to the loss of many organisms that rely on wetland habitat, including birds, amphibians, fish, mammals and many insects. As one example, many dragonfly and damselfly species are declining worldwide as the freshwater wetlands where they breed are drained and filled in. A marsh or bog may not look like a productive place, but wetlands teem with life and are critically important parts of our environment.

Disclosure statement
Jon Sweetman receives funding from the US EPA for work on wetland restoration. He is affiliated with the Society for Freshwater Science, the Ecological Society of America, and the Society of Wetland Scientists