By Ysabelle Kempe for Smart Cities Dive.
Broadcast version by Suzanne Potter for California News Service reporting for the Solutions Journalism Network-Public News Service Collaboration

Reflective pavement coating helped cool down one of Los Angeles' hottest neighborhoods over a year-long period, according to a recently published study in Environmental Research Communications, but some researchers argue in favor of increasing shade as a better way to protect people from dangerously high temperatures.

The research on the installation in LA's Pacoima neighborhood is "probably the most comprehensive study on controlled cool pavement" due to the large amount of data and variables considered, said Haider Taha, an atmospheric modeler, president of the research company Altostratus and the study's author.

Over 700,000 square feet of dark asphalt surfaces in Pacoima were covered with solar-reflective pavement coating in the summer of 2022 through a partnership between local nonprofit Climate Resolve and roofing and waterproofing manufacturer GAF, which provided the coating.

Pavement that reflects, rather than absorbs sunlight, has emerged as a tool cities are considering to mitigate theincreasing danger of extreme heat.

GAF funded the recently released peer-reviewed study, although the company had no role in the study's design, data collection, modeling or analysis of the results. The research found that during an extreme heat event, the cool pavement-covered area saw ambient air temperatures that were as much as 3.5 degrees Fahrenheit cooler than those in the adjacent neighborhood. On sunny days, ambient air temperatures were reduced by up to 2.1 degrees Fahrenheit. During summer nights, they were reduced by up to 0.5 degrees Fahrenheit. The coating also lowered surface temperatures by up to around 10 degrees Fahrenheit.

What does that mean for the people who live in Pacoima? Melanie Torres, a resident and the Pacoima Beautiful's Cool Community Project organizing manager, said she's felt a difference. Pacoima Beautiful is a local environmental justice organization and helped GAF and Climate Resolve with community engagement for the reflective pavement project.

Torres often eats lunch in one of the parks where the coating is deployed. "I can just sit on the grass near the basketball court and feel just the breeze - and not necessarily a hot breeze," she said. A food vendor who frequents the neighborhood told Torres that "she feels the difference in the breeze more than anything.

Torres said she hasn't heard any complaints about the reflective pavement coating during her community engagement efforts. However, reflective pavement is not immune to criticism.

Some researchers have found that the solar energy reflected off cool pavement can actually increase how hot pedestrians feel. Taha, however, said that his study indicated an "improvement in thermal sensation," noting that every location within Pacoima has "its own dynamics" that could lead to slightly different results. Mean radiant temperature - a measurement of thermal comfort - "goes up and down. It's not always cooler," he said. "The overwhelming effect is the cooling."

But no matter how effective reflective coatings are, they can't beat shade, V. Kelly Turner, associate director of the University of California, Los Angeles' Luskin Center for Innovation and an associate professor of urban planning and geography, said in an email. Shade can cool people by up to 30 degrees Celsius, or 54 degrees Fahrenheit, in hot, dry environments, she said.

"No change in surface will protect the body from heat as effectively as preventing sunlight from hitting the body in the first place," she said. "Shade - blocking the sun with trees, canopies, and tall features like walls and buildings - is by far the most effective way to cool people outdoors."

She noted that reflective pavement doesn't have a large effect on air temperature unless it is deployed widely and, even when that happens, the cooling benefit is moderate. She believes that reflective pavement is an appropriate choice in locations where it would be difficult to replace surfaces that absorb a lot of heat with "something else like vegetation and where the goal of mitigating surface material contributions to heat is the priority as opposed to protecting people's bodies outdoors."

"I think cities should see reflective pavement as one tool among many, if deployed comprehensively, that could mitigate the regional urban heat island," Turner said. "They should see this goal as parsimonious from the public health goal of protecting people's bodies from the sun."


Ysabelle Kempe wrote this article for Smart Cities Dive.


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Chesapeake Bay has added more than six billion oysters since 2017 through the Chesapeake Oyster Alliance.

And last year, the Chesapeake Bay Foundation grew more than 100,000 oysters to be placed in the bay.

But oyster populations were not always on the upward trend. Overharvesting, pollution, and disease caused massive declines in oyster populations.

Today, only 3% of historic native oyster populations in the bay remain.

Jessica Lutzow, Virginia oyster restoration specialist with the Chesapeake Bay Foundation, says the mollusks are considered the "popular kid."

Oysters in Chesapeake Bay are a keystone species, providing many benefits to the bay environment.

"They filter up to 50 gallons of water a day," said Lutzow. "We're talking about a three- to four-inch oyster filtering that much water a day. You have this little, resilient creature that's doing so much for it all at once."

Oysters are also consequential in preserving coastlines. When oyster reefs form, they serve as natural buffers against coastal erosion and storm surges.

Oyster reefs disperse wave energy to protect coasts from the full force of severe storms. To grow oysters, a volunteer suspends a wire cage full of baby oysters - also called spats - from a dock or marina.

The only upkeep required is keeping the cage clean to provide enough waterflow to the oysters. Lutzow said she's encouraged by these oyster milestones.

"It's such a positive outcome," said Lutzow, "and I see it progressing in the future as people really start to fully understand how important these creatures are, and how important the other animals and plants that are on the reefs are as well. The oysters can help create that habitat to keep those animals thriving as well. "

Conservationists are currently working to reach their goal of adding 10 billion oysters to the bay by the end of the year.

The Chesapeake Bay Foundation expects they will grow nearly 200,000 oysters this year.




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Environmental groups are suing South Fork Coal Company, alleging the company has repeatedly violated federal law in Greenbrier County.

The lawsuit said the company has continued to discharge pollutants into nearby waterways at levels exceeding legal limits. Environmental advocates said despite years of dumping pollutants, the state's environmental protection department has not taken action to stop South Fork Coal.

Andrew Young, chair of the extractive industries committee for the West Virginia Highlands Conservancy, said the lawsuit is asking for an injunction to immediately stop the dumping and ensure the company properly reclaims the land.

"We noticed that South Forks' own monitoring data showed that they were often discharging pollutants like iron, manganese, in excess of their legal limits," Young pointed out. "The allegations are based largely on what the company itself is reporting."

Advocates said the five mines in the lawsuit all discharge pollutants into the Laurel Creek Watershed and/or the South Fork of the Cherry River Watershed. Both streams feed into the Gauley River, an internationally renowned destination for whitewater rafting and kayaking, and home to the endangered candy darter.

The lawsuit also highlighted the company's failure to submit required water quality assessments and reclaim unused sites. Young argued the company's neglect of water and land standards puts local communities and the outdoor recreation economy at risk.

"The mines at issue here lie adjacent to the Monongahela National Forest, and it's less than six miles from the world-renowned Cranberry glades and Cranberry Glades Wilderness Area," Young explained.

The state's tourism industry brought in nearly $9 billion last year. According to the governor's office, more than 75 million visitors traveled to the Mountain State last year, and spent more than $6 billion.

By Nina B. Elkadi for Sentient.
Broadcast version by Mark Moran for Iowa News Service reporting for the Sentient-Public News Service Collaboration

A new report from environmental watchdog group Food & Water Watch suggests that almost 2 million fish were killed from manure spills in Iowa between 2013 and 2023. The 179 spills occurred throughout the state, with a major hotspot for spills in the northwest corner of the state. Earlier this year, the group reported that Iowa factory farms produce more waste than any other state, at 109 billion pounds of manure annually, based on U.S. Department of Agriculture data.

The report and accompanying map, released on Dec. 9, designated over 700 segments of Iowa water as “impaired” — not meeting the standards necessary to support aquatic life, public water supplies or recreation. Details include where in the state spills occur, who owns the operation and if they are repeat offenders.

Manure spills in the state of Iowa have contributed to what environmental advocacy groups call a water quality crisis. In the capital city of Des Moines, the local water supply has one of the world’s largest nitrate removal facilities. Nitrate is the resulting chemical of manure that is not absorbed by the soil or crops. Due to high levels of nitrate in water, which can cause blue baby syndrome in children and colon cancer in adults, the Des Moines Water Works has to run its nitrate removal system more frequently as the situation worsens — at a cost of anywhere from $10,000 to $16,000 per day, which falls entirely on utility customers.

“When you think about the nature of what they’re spilling and the quantities of what they’re spilling, it’s the difference between life and death, and people are being strapped down with medical debt and suffering in a prolonged way,” Food & Water Watch Iowa Organizer Michaelyn Mankel tells Sentient.

According to the report, the Iowa Department of Natural Resources fined 171 of the 179 offenders at $635,808 over the ten-year period it studied. That’s less than half of what Des Moines Water Works spent on its nitrate removal system in 2015, at $1.4 million. There are gaps in the state reporting as well. The total volume of the spills is difficult to determine because most reports do not contain information on how much manure is spilled. And in those that do note volume, the range is anywhere from 500 to 1 million gallons.

“The fines that the DNR has leveled against these companies do not represent restitution for the damage that they’re causing to Iowa,” Mankel says. “They also don’t represent a real demand that these corporations change the way that they’re doing business.”

In 2024 alone, the Iowa Department of Natural Resources documented 13 fish kill events, one of which regulators directly tied to animal waste. This one “anthropogenic” spill in northwest Iowa — caused by dairy manure land-applied runoff —killed anywhere from 100,001-500,000 fish.

Many concentrated animal feeding operations operate without the proper discharge permits, rendering their spills more difficult to track. In October, the Ninth Circuit Court of Appeals struck down a petition from 13 groups — including Food & Water Watch — calling for stricter regulation and enforcement of the Clean Water Act. Today, Food & Water Watch is calling for a “Clean Water for Iowa Act” to be passed in the state legislature. The act would require all medium and large-scale concentrated animal feeding operations to get National Pollutant Discharge Elimination System permits.

This report and map are released in the midst of a health crisis in the Midwest, which some observers and critics argue is tied to, or exacerbated by, large-scale industrialized agriculture. Mankel points to cancer incidence in the state of Iowa; it’s the only state in the country with rising cancer rates (though other factors, like obesity and alcoholism rates may play a role).

“We’re paying for it,” Mankel says. “I really want Iowans to understand that these problems are a policy choice, and that we are being burdened with paying the true cost of massive profits that these corporations are reaping from our state, and that’s a very intentional choice on behalf of lawmakers.”


Nina B. Elkadi wrote this article for Sentient.


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