Day: September 27, 2021

#Colorado Parks & Wildlife and Partners stock greenback cutthroat trout into the West Fork of #ClearCreek

Members from Colorado Parks and Wildlife, Trout Unlimited, US Fish and Wildlife Service, the USDA Forest Service, Rocky Mountain National Park and the Greenback Cutthroat Trout Recovery Team meet up by Jones Pass before stocking 6,000 greenback cutthroat trout into the West Fork of Clear Creek September 22, 2021. Photo credit: Colorado Parks & Wildlife

Here’s the release from Colorado Parks & Wildlife (Reid Armstrong and Jason Clay):

The USDA Forest Service, Colorado Parks and Wildlife, Trout Unlimited, and a host of volunteers stocked 6,000 greenback cutthroat trout fry into Upper West Fork Clear Creek near Jones Pass on Wednesday, Sept. 22.

This is the third location in the Clear Creek drainage where the Greenback Cutthroat Trout Recovery Team has stocked greenbacks into, joining Dry Gulch and Herman Gulch.

“Greenback cutthroat trout reintroductions such as the West Fork Clear Creek are really only able to occur due to the coordination and efforts of each cooperating agency and non-profit partners such as Colorado Parks and Wildlife, Trout Unlimited, US Fish and Wildlife Service, the USDA Forest Service and the Greenback Cutthroat Trout Recovery Team to name a few,” said Valerie Thompson, South Zone Fisheries Biologist for the Forest Service. “Each partner contributes in unique ways that enable the success of major conservation projects such as this one on West Fork Clear Creek, where over fourteen years of stream health data was collected, an old mine site was remediated, and stream banks were restored to allow for habitat that is suitable to sensitive aquatic life and now a new home to the Colorado State Fish, the Greenback Cutthroat Trout.”

The fact that this tributary was fishless to begin with made it a good candidate for the greenbacks, among other factors.

“We’ve done temperature monitoring and the temperatures are conducive to support natural reproduction,” said Paul Winkle, Aquatic Biologist for CPW. “It is a goal to get another population of fish on the landscape, so this is definitely an important thing for the recovery of greenbacks.”

This stretch of stream was fishless due to downstream barriers, such as a quarter-mile-long culvert underneath the Henderson Mine Site, among other natural barriers. That saved some heavy lifting, not requiring a reclamation of the stream to remove other non-native species of fish. Removal of all other species is necessary to ensure the successful reestablishment of greenbacks, which are native to the South Platte River basin.

“We knew that there were no fish in that section of Clear Creek and what a great thing to be able to put fish in without having to do a reclamation,” Winkle said. “The more streams of greenbacks we stock along the Front Range drastically improves the conservation status of the species.”

Today, the greenbacks are listed by the U.S. Fish and Wildlife Service as a threatened species. Greenbacks have previously been stocked into Herman Gulch, Dry Gulch, the East Fork of Roaring Creek and Zimmerman Lake. Those all reside within the South Platte River drainage. The sixth body of water in Colorado where the official state fish currently resides is in Bear Creek outside of Colorado Springs.

These rare fish, twice believed to be extinct, are descendants of the last wild population of native greenback cutthroat trout. Researchers from CU Boulder in partnership with CPW discovered in 2012 that the cutthroat in Bear Creek were the last remaining population of greenback cutthroat trout.

CPW’s Mount Shavano Hatchery in Salida is responsible for rearing and delivering all greenbacks that get stocked. They hatch fertilized eggs in its Isolation Unit. Extra milt collected from male greenbacks in Bear Creek goes to the U.S. Fish and Wildlife Service’s Leadville National Fish Hatchery to fertilize eggs from the greenbacks in its brood stock.

The eggs are then taken to Salida to be hatched and eventually stocked onto the landscape at various sizes. Sometimes those fish are of fingerling lengths (one to two inches), sometimes they are fry. Fry is a recently hatched fish that has reached the stage where its yolk-sac has almost disappeared and its swim bladder is operational to the point where the fish can actively feed for itself.

“Trout Unlimited and our West Denver Chapter have a long history of supporting the Forest Service and Colorado Parks and Wildlife in stewardship of the Clear Creek drainage,” said David Nickum, executive director of Trout Unlimited. “We are so pleased to see those efforts coming to fruition with our volunteers working side by side with our partners to finally return greenbacks to their home waters in the West Fork headwaters.”

Stocking Greenback cutthroat trout September 22, 2021. Photos credit: Colorado Parks & Wildlife

When A #Wildfire Ends, The Work To Protect #Water Is Just Getting Started — KUNC

Aerial mulching. Photo credit: Colorado State Forest Service

From KUNC (Alex Hager):

It’s been almost exactly a year since the Cameron Peak Fire tore through the foothills outside of Fort Collins, Colorado, on its way to becoming the largest fire in state history. Now, restoration efforts are underway. About 1 million people rely on water moving through this canyon, and one of the most effective ways to protect the area’s watershed uses these helicopters. Instead of scooping up water to drop on flames, pilots dip low and pick up bulging nets full of wood mulch to dump on the charred hillside.

Randy Gustafson, water resource administrator for the City of Greeley, looks on as a helicopter hovers near the ground, rumbling loudly over a pile of mulch bigger than a house. Then, it’s off as quickly as it came, zipping back and forth into the burn scar with heaving payloads in tow…

Even though Greeley is a two-hour drive away from this “aerial mulching” operation in Poudre Canyon, this is where the city’s water comes from. Snowmelt and rain make their way down from the foothills into the Cache la Poudre River before that water is piped over to the city. But Gustafson said a charred slope is slick like a frying pan. Water will run off of it, carrying dirt, ash and other debris into that water supply. So his team has to stabilize the hillside with mulch.

“I look at the Poudre as a living organism,” Gustafson said. “How do you keep it functional and operational and make it produce good, clean water for everybody down below?”

[…]

A burnt sign on Larimer County Road 103 near Chambers Lake. The fire started in the area near Cameron Peak, which it is named after. The fire burned over 200,000 acres during its three-month run. Photo courtesy of Kate Stahla via the University of Northern Colorado

Gustafson’s team is just one part of the city’s strategy to keep the water clean. Another effort is underway above Chambers Lake, less than a mile from where the fire began. Here, fire debris threatens to cause harmful algae blooms in the reservoir. So big bundles of spongy wood shavings, held together by biodegradable nets, are laid out on the hillside.

“They form a baffle,” Gustafson said. “They stop the debris, soil, ash, and keep it from coming down into the reservoir.”

On a visit to the site, Gustafson shows how the baffles are successfully holding back sludgy piles of gray dirt in one of the most severely burned parts of forest…

In the grand scheme of things, though, these efforts could be little more than a Band-Aid. The expensive and time-consuming mulching work can only cover a fraction of the burn’s sprawling footprint. And more are likely on the way…

“These megafires are unfortunately not going to be going anywhere anytime soon,” said Hally Strevey, director of the Coalition for the Poudre River watershed. “We’re trying not to lose hope. There are plenty of things we can still do, working together collaboratively.”

That includes her organization’s precautionary forest management in areas prone to burning. The fact it’s carried out by a watershed group just further emphasizes how deeply water and fire are connected. Even after a fire is put out, it takes a lot of work to keep the water clean.

But restoration projects like the one in Poudre Canyon are not cheap. Keeping just one helicopter in the air costs $87 per minute. Greeley’s deputy water director, Adam Jokerst, says the high costs are worth it for two reasons…

The money spent on recovery work is also a precautionary measure against purification costs that could be incurred if ash finds its way into the water supply…

Greeley’s water team says restoration work will carry into the next few years, but because of the size and severity of the burn, it may never truly be the same as it was before the fire.

Chambers Reservoir July 2016. Photo credit: Greg Hobbs

Essay: Hot Wind Over Cool Water — The Corner Post #GreenRiver #ColoradoRiver #COriver #aridification

From the My Public Lands Magazine, Summer 2014: “Midnight Mustang” While camping overnight on a solo rafting trip down Utah’s aptly-named “Desolation Canyon,” BLM River Ranger Mick Krussow has a midnight rendezvous with a wild mustang… story by Mick Krussow, BLM Utah illustration by Matt Christenson, BLM Oregon Read the story: http://on.doi.gov/1n1pepx. By Bureau of Land Management – My Public Lands Magazine, Summer 2014, Public Domain, https://commons.wikimedia.org/w/index.php?curid=42090064

From The Corner Post (Hannah Holm):

A thin haze appeared in the afternoon between our rubber boats and distant fins of burnt-orange rock, while a hot wind touched our faces, hands—any skin not taking refuge beneath cool, wet cloth. Later, the haze thickened, mixed with cirrus clouds and gave the golden-hour light a reddish tint.

The river still rushed by, and vibrant leaves in our camp’s young cottonwood gallery fluttered above me. The voice of the yellow-breasted chat that had berated us from cliff walls echoed in my mind, along with the scent of sage and sumac from a lunchtime visit to petroglyphs up a tributary canyon. I was fully immersed in this place, Desolation Canyon on the Green River in eastern Utah. No internet, no phone reception, no news or other distractions. Just the river, the canyon, and my companions on this week-long writing retreat.

But the sky’s tint and the hot wind hinted at what was happening outside the sheltering canyon walls. Record-breaking heat and nearby wildfires, starting early this year. The river itself gave more clues, to those who knew how to recognize them. Low flows and tame rapids, in June. A bear and cub were by the river when they should have been finding forage at higher elevations. We followed a long, irregular stripe of mineral crust punctuated by half-dead clumps of grass on the eastern wall. An extended seep that wasn’t seeping, the ghosts of hanging gardens.

Colorado Basin River Forecast Center Drought Monitor Map September 21, 2021.

Extended drought—or more accurately, aridification—is making its mark on the landscape and on people’s lives. News that I didn’t read during those days on the river was about ever shrinking forecast inflows into Lake Powell and how the states that share the Colorado River might manage reduced water supplies within a legal framework based on imagined bounty.

I write about these things, too, but on the river, I was trying to find words beyond my habitual short-hand to describe our hydrology and water policy developments. For over ten years, I’ve been learning and communicating about how people built an unbalanced system in the Colorado River Basin, constructing the plumbing for demands to exceed supplies, and how we can worm our way out of the worst consequences of that fundamental problem for fish and farms. I still think that matters, and I still think we have options.

But the river showed me that the transformation in our landscape is bigger than that, beyond the reach of our tinkering. Even far from ditches and diversions, seeps go dry and forage for bears thins out. We can micromanage irrigation water to get the most from every drop, clean up toilet water to a pristine state, and adjust reservoir releases to help endangered fish. We can pay farmers to fallow fields. But we can’t pay the hot wind to stop taking water from the sage, the sumac and the dirt. There’s no negotiating on this point, and no escape, not even in one of the most remote canyons in the lower 48.

Aridification carries a heavier emotional weight when I see it on the land than when I read papers about it or watch presentations in windowless conference rooms. It’s hard to see things change, irrevocably. To walk through a sick forest and know that it won’t grow back the same. To know that going away from people and the things we’ve built can’t actually take me back to a less damaged state of nature.

Since that trip down Desolation Canyon, back home in Grand Junction, Colorado, the temperatures have eased from the 100s into the 90s, and the summer rains we’ve missed for a couple of years have come back. It’s a welcome respite, and the dwarf ash and pinyon pines I see on my trail runs look perkier than they have in ages. I know these rains aren’t enough to reverse the harsh trend we’re in, but they lift my spirits and give all living things a break, a chance to gather strength before facing the next onslaught of hot wind.

We can’t turn back the clock and we can’t run away, but we can gather strength from an unexpected storm. We can diligently tinker where tinkering can work. And we can dip cloth into cool water, feel it dribble across our skin, and listen to the birds as we drift down the river.

Working with Nature to Secure a Stable Water Future for the West — The Walton Family Foundation #ColoradoRiver #COriver #aridification

Photo credit: The Walton Family Foundation

From The Walton Family Foundation (Moira Mcdonald):

In the Colorado River Basin, the Walton Family Foundation is committed to ensuring a healthier watershed with improved flows that help the region adapt to climate change

The future of the American West depends on water – on having enough of this scarce resource to sustain the region’s growing population and maintain a healthy environment.

In the face of extreme droughts in the Colorado River Basin, the threat of water shortages is real and immediate. And the need to find solutions so people and nature can thrive together has never been more urgent.

Even as climate change portends a hotter, drier future for the Colorado River, we believe there are practical reasons to be hopeful and take action to protect the region’s water.

Signing ceremony for the Colorado River upper and lower basin Drought Contingency Plans. Back Row Left to Right: James Eklund (CO), John D’Antonio (NM), Pat Tyrell (WY), Eric Melis (UT), Tom Buschatzke (AZ), Peter Nelson (CA), John Entsminger (NV), Front Row: Brenda Burman (US), and from DOI – Assistant Secretary of Water and Science Tim Petty. Photo credit: Colorado River Water Users Association

When the seven Colorado River Basin states signed a historic drought plan two years ago, they sealed a conservation victory to manage the water supply, and end chronic overuse of the river. A separate agreement between the U.S. and Mexico ensures additional water efficiency while also providing water explicitly for the river and habitat restoration.

Jayne Harkins (seated, far left), as executive director of the Colorado River Commission of Nevada, was one of the signers in 2017 of domestic agreements that were part of Minute 323, the addendum to the 1944 U.S.-Mexican Water Treaty. (Image: U.S. Bureau of Reclamation)

The Walton Family Foundation supported both of those agreements and we will continue to support water conservation measures that help us all find a pathway through coming water shortages.

In the foundation’s new five-year Environment program strategy, we will increase our efforts to get more water into the Colorado River and its tributaries by supporting natural infrastructure projects throughout the basin. By working with nature, rather than against it, we can build healthier watersheds with improved flows that help us adapt to climate change.

To confront the challenges facing the Colorado River, we will increase engagement with communities across the region – including ranchers, tribal leaders, and local communities – to improve the health of nature and create long-term, collaborative plans for smart water management.

We’re also working with partners looking for ways to increase the use of nature-based solutions and innovative practices that use less water and leave more water in the river. We see progress in places like Arizona’s Verde River, a Colorado River tributary, where farmers are shifting production from water-intensive crops like alfalfa and finding new markets for barley, which requires less water and improves river flows.

Because we believe those closest to the water challenges in the Colorado River Basin are closest to the solution, we’re working more intentionally with community organizations and increasing outreach to diverse constituencies who deserve a greater voice in water management decisions that impact them.

It’s said that necessity is the mother of invention. There are no easy solutions to the water challenges now gripping parts of the West. But we believe the urgency of this moment can be a catalyst for creativity and collaboration that ensures a secure and stable water future for the region.

Click to enlarge. Graphic credit: The Walton Family Foundation

#LakePowell Could Stop Producing Hydropower in 2023 Due to Worsening #Drought — Yale Environment 360 #ColoradoRiver #COriver #aridification

Lake Powell’s Glen Canyon Dam. ALIK GRIFFIN VIA FLICKR

From Yale Environment 360:

Dwindling water levels at Lake Powell could make it impossible for its dam to generate hydropower in 2023, according to new projections from the U.S. Bureau of Reclamation.

Projection of Lake Powell end-of-December reservoir elevations. The colored region, or cloud, for the hydrology scenario represents the minimum, 10th percentile, 90th percentile, and maximum of the projected reservoir elevations. Solid lines represent historical elevations (black), and median projected elevations for the scenario (yellow). Dashed gray lines represent important elevations for operations, and the vertical line marks the adoption of the 2019 Drought Contingency Plans. Graphic credit: Bureau of Reclamation

Lake Powell, the second-largest human-made reservoir in the United States, stretches from northern Arizona into southern Utah on the Colorado River. With severe heat and persistent drought sapping the river, water levels at Lake Powell fell to 3,554 feet this summer, the lowest level on record. If trends continue, there is a 34 percent chance that, in 2023, water levels could dip below 3,490 feet, the minimum needed to produce hydropower at the Glen Canyon Dam, the bureau said. The dam supplies power to 5.8 million customers.

“The latest outlook for Lake Powell is troubling,” Wayne Pullan, the bureau’s Upper Colorado Basin regional director, said in a statement. “This highlights the importance of continuing to work collaboratively with the Basin States, Tribes and other partners toward solutions.”

Projection of Lake Mead end-of-December reservoir elevations. The colored region, or cloud, for the hydrology scenario represents the minimum, 10th percentile, 90th percentile, and maximum of the projected reservoir elevations. Solid lines represent historical elevations (black), and median projected elevations for the scenario (yellow). Dashed gray lines represent important elevations for operations, and the vertical line marks the adoption of the 2019 Drought Contingency Plans. Graphic credit: Bureau of Reclamation

At Lake Mead, further down the Colorado River, there is 22 percent chance that in 2025 water levels will dip below 1,000 feet, close to the level where water can no longer flow through the Hoover Dam, the bureau said. Drought has already limited hydropower in other parts of the West. In August, officials shut down the Hyatt Power Plant at Lake Oroville in northern California after water levels dropped near the minimum needed to generate electricity.

Colorado Basin River Forecast Center Drought Monitor Map September 21, 2021.

The Colorado River’s flow has fallen roughly 20 percent over the last century, and rising temperatures are responsible for more than half of that decline, according to a 2020 study. The region is now enduring its worst drought in 1,250 years, fueling a crisis on the river. With water supplies growing increasingly scarce, some have called for draining Lake Powell — and shutting off the Glen Canyon Dam — to supply more water to Lake Mead downstream.

The West Urgently Needs Federal Funds to Address #Drought, #Wildfire, and #ClimateChange — Audubon

American White Pelican. Photo: Joanne Wuori/Audubon Photography Awards

From Audubon (Karyn Stockdale):

With big spending bills on the horizon, Congress needs to prioritize water security for people and birds.

As Congress considers several major pieces of legislation to address urgent needs in the United States, Audubon’s Western Water team is keeping a close eye on funds to address the unprecedented drought emergency in the West. Congress should use all available options to invest in immediate and long-term solutions to mitigate current disasters and enhance the climate resilience of states affected by historic drought conditions.

In the West, snowpack has been at historic lows, and the major reservoirs that supply drinking water for 40 million people along the Colorado River are now less than half-full. This summer, more than 93% of the western United States has experienced drought conditions.

2021 has brought yet another year of record-breaking climate extremes. The Colorado River’s two largest reservoirs—Lake Mead and Lake Powell—are at their lowest levels ever. So is Great Salt Lake. The Rio Grande, Salton Sea, Klamath River Basin, and wetlands and tributaries across the West are also struggling. Because of the dire situation on the Colorado River, the Bureau of Reclamation announced that 2022 will bring unprecedented water shortages to Arizona, Nevada and the Republic of Mexico.

The ongoing drought crisis has been accelerated by climate change, which is the single biggest threat to birds, with more than 67% of bird species in the Americas at risk of extinction if we fail to meet our goals of reducing greenhouse gas emissions.

Currently, Congress is working to pass several important funding bills that will significantly improve our waterways and wetlands in the West—for people and birds.

Specifically, as Congress considers funding packages, Audubon is supporting the following priorities and projects that give federal agencies critically needed resources:

  • U.S. Bureau of Reclamation, Drought response programs and projects:
    • $500M for the Colorado River Drought Contingency Plan. This will address near-term risks to Lake Powell and Lake Mead in the face of significant water scarcity.
    • $300M for the implementation of Minute 323 to the 1944 Mexican Water Treaty, which includes funding for binational water conservation investments, development and maintenance of critical bird habitat in the Colorado River Delta.
    • $250 million to support the Salton Sea Projects Improvements Act to work with the State of California, local counties, tribal governments, and nonprofits to mitigate the environmental and public health crises—a result of the Sea’s receding shoreline.
    • $400 for WaterSMART, including $100M for natural infrastructure. WaterSMART programs provide a federal cost-share for the development of local watershed management programs; improve water delivery, efficiency, and reliability; support multi-benefit projects; and reduce conflicts over water-use in the West.
    • $50 million for multi-purposes watershed protection and restoration projects in the West.
    • $50 million for Colorado River Upper Basin Fish Recovery Implementation Plans and Endangered Species Act compliance in the Lower Colorado River Basin.
  • United States Geological Survey (USGS) science and monitoring:
    • $200 million for USGS science and monitoring. These additional resources could support programs like a federally coordinated assessment of the conservation needs across Saline (Salt) Lake Ecosystems, championed by Audubon and the development of OpenET, an online, satellite-driven water data platform.
  • U.S. Fish and Wildlife Service (FWS)
    • $150 million for the effective and efficient implementation of the National Environmental Policy Act (NEPA) and $40 million for Endangered Species Act interagency consultation. This funding will help ensure that infrastructure projects can advance efficiently while avoiding adverse environmental impacts.
    • $162M for Klamath River Basin and Wildlife Refuge to support infrastructure. We also encourage Congress to find additional funding to support water acquisition or invest in permanent solutions that protect fish and wildlife in Klamath. This includes a permanent bird hospital and more funding for operations and maintenance.
    • $25M for the Lahontan Valley and Pyramid Lake Fish and Wildlife Fund to ensure long-term availability of water at important habitats.
  • U.S. Department of Agriculture (USDA):
    • Double the amount of funding for Farm Bill voluntary, private land conservation programs (such as the Environmental Quality Incentives Program), which provide critical financial and technical assistance to help landowners protect and enhance natural spaces on their property. Funding through these programs should prioritize projects that increase bird habitat, benefit underserved farmers and ranchers, and provide carbon sequestration and increased resilience co-benefits.
    • ​More than $2B in additional funding for the U.S. Forest Service for restoration, land management, and emergency response recent wildfires.

These funds will make drought, limited water supplies, and decreasing bird habitat less dire. After this year’s catastrophic wildfires and historic drought, we urge Congress—and particularly our delegations in the West—to ensure that federal investments increase community resilience to the effects of climate change by promoting nature-based solutions for restoring watersheds and ecosystems.

In addition, Congress has several pending bills with bipartisan support that respond to the many needs of tribal communities and western states’ water supply needs that we are supporting, including access to clean water and water settlements.

We’ll keep you posted as this legislation moves forward. Be sure to sign up for our Western Water Action Network to get the most updated information.

Evidence shows that, yes, masks prevent #COVID19 and surgical masks are the way to go — The Conversation


What type of mask is best?
Brais Seara/Moment via Getty Images

Laura (Layla) H. Kwong, University of California, Berkeley

Do masks work? And if so, should you reach for an N95, a surgical mask, a cloth mask or a gaiter?

Over the past year and a half, researchers have produced a lot of laboratory, model-based and observational evidence on the effectiveness of masks. For many people it has understandably been hard to keep track of what works and what doesn’t.

I’m an assistant professor of environmental health sciences.
I, too, have wondered about the answers to these questions, and earlier this year I led a study that examined the research about which materials are best.

Recently, I was part of the largest randomized controlled trial to date testing the effectiveness of mask-wearing. The study has yet to be peer reviewed but has been well received by the medical community. What we found provides gold-standard evidence that confirms previous research: Wearing masks, particularly surgical masks, prevents COVID-19.

Laboratory studies help scientists understand the physics of masks and spread.

Lab and observational studies

People have been using masks to protect themselves from contracting diseases since the Manchurian outbreak of plague in 1910.

During the coronavirus pandemic, the focus has been on masks as a way of preventing infected persons from contaminating the air around them – called source control. Recent laboratory evidence supports this idea. In April 2020, researchers showed that people infected with a coronavirus – but not SARS-CoV-2 – exhaled less coronavirus RNA into the air around them if they wore a mask. A number of additional laboratory studies have also supported the efficacy of masks.

Out in the real world, many epidemiologists have examined the impact of masking and mask policies to see if masks help slow the spread of COVID-19. One observational study – meaning it was not a controlled study with people wearing or not wearing masks – published in late 2020 looked at demographics, testing, lockdowns and mask-wearing in 196 countries. The researchers found that after controlling for other factors, countries with cultural norms or policies that supported mask-wearing saw weekly per capita coronavirus mortality increase 16% during outbreaks, compared with a 62% weekly increase in countries without mask-wearing norms.

A man wearing a surgical mask handing a mask to a woman working at a vegetable stand.
Researchers gave surgical masks to adults in 200 villages in Bangladesh to test whether they reduce COVID-19.
Innovations for Poverty Action, CC BY-ND

Large-scale randomized mask-wearing

Laboratory, observational and modeling studies, have consistently supported the value of many types of masks. But these approaches are not as strong as large-scale randomized controlled trials among the general public, which compare groups after the intervention has been implemented in some randomly selected groups and not implemented in comparison groups. One such study done in Denmark in early 2020 was inconclusive, but it was relatively small and relied on participants to self-report mask-wearing.

From November 2020 to April 2021, my colleagues Jason Abaluck, Ahmed Mushfiq Mobarak, Stephen P. Luby, Ashley Styczynski and I – in close collaboration with partners in the Bangladeshi government and the research nonprofit Innovations for Poverty Action – conducted a large-scale randomized controlled trial on masking in Bangladesh. Our goals were to learn the best ways to increase mask-wearing without a mandate, understand the effect of mask-wearing on COVID-19, and compare cloth masks and surgical masks.

The study involved 341,126 adults in 600 villages in rural Bangladesh. In 300 villages we did not promote masks, and people continued wearing masks, or not, as they had before. In 200 villages we promoted the use of surgical masks, and in 100 villages we promoted cloth masks, testing a number of different outreach strategies in each group.

Over the course of eight weeks, our team distributed free masks to each adult in the mask groups at their homes, provided information about the risks of COVID-19 and the value of mask-wearing. We also worked with community and religious leaders to model and promote mask-wearing and hired staff to walk around the village and politely ask people who were not wearing a mask to put one on. Plainclothes staff recorded whether people wore masks properly over their mouth and nose, improperly or not at all.

Both five weeks and nine weeks after starting the study, we collected data from all adults on symptoms of COVID-19 during the study period. If a person reported any symptoms of COVID-19, we took and tested a blood sample for evidence of infection.

A woman exiting a store with signs showing mask requirements on the door.
Based on current evidence, many places across the U.S. have some form of mask requirements.
AP Photo/LM Otero

Mask-wearing reduced COVID-19

The first question my colleagues and I needed to answer was whether our efforts led to increased mask-wearing. Mask usage more than tripled, from 13% in the group that wasn’t given masks to 42% in the group that was. Interestingly, physical distancing also increased by 5% in the villages where we promoted masks.

In the 300 villages where we distributed any type of mask, we saw a 9% reduction in COVID-19 compared with villages where we did not promote masks. Because of the small number of villages where we promoted cloth masks, we were not able to tell whether cloth or surgical masks were better at reducing COVID-19.

We did have a large enough sample size to determine that in villages where we distributed surgical masks, COVID-19 fell by 12%. In those villages COVID-19 fell by 35% for people 60 years and older and 23% for people 50-60 years old. When looking at COVID-19-like symptoms we found that both surgical and cloth masks resulted in a 12% reduction.

The body of evidence supports masks

Before this study there was a lack of gold-standard evidence on the effectiveness of masks to reduce COVID-19 in daily life. Our study provides strong real-world evidence that surgical masks reduce COVID-19, particularly for older adults who face higher rates of death and disability if they get infected.

Policymakers and public health officials now have evidence from laboratories, models, observations and real-world trials that support mask-wearing to reduce respiratory diseases, including COVID-19. Given that COVID-19 can so easily spread from person to person, if more people wear masks the benefits increase.

So next time you are wondering if you should wear a mask, the answer is yes. Cloth masks are likely better than nothing, but high-quality surgical masks or masks with even higher filtration efficiency and better fit – such as KF94s, KN95s and N95s – are the most effective at preventing COVID-19.The Conversation

Laura (Layla) H. Kwong, Assistant Professor of Environmental Health Sciences, University of California, Berkeley

This article is republished from The Conversation under a Creative Commons license. Read the original article.