What’s Left When Lakes Vanish

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A couple of times a month, Mariela Loera goes knocking on doors in California’s Eastern Coachella Valley. Part of her job, as a policy advocate with the nonprofit Leadership Counsel for Justice and Accountability, is to provide a listening ear to members of the community, many of whom work in the region’s lush farms cultivating citrus, dates, and other winter crops.

Most of the people Loera speaks with are middle-aged mothers. At nearly every house, she hears the same thing: “One or more of my kids has asthma or some sort of respiratory illness.” If it’s summer, she might hear complaints of headaches and nosebleeds due to the poor air quality.

“It’s the same story that’s repeated with nearly everyone I talk to,” says Loera, who has been working with community members for close to 2 years. “People are trying to understand why this is happening.”

In most instances, whittling a disease down to a single cause is difficult, if not impossible. But in the case of the Eastern Coachella Valley, one culprit looms large: the nearby Salton Sea. “It’s definitely one of the main contributors to the air quality in the region, and therefore symptoms,” says Loera.

The problem with the 340-square-mile Salton Sea– whose name is a misnomer, as it’s actually California’s largest lake – is that it’s shrinking. It’s a fate faced by a handful of other lakes around the country and throughout the world – the result of upstream water diversions, global warming, human mismanagement, and other factors. 

Owens Lake in California, for instance, has shrunk to less than a third of its former area; while the Great Salt Lake in Utah reached its lowest level since 1847 this July. Iran’s Lake Urmia, once the largest lake in the Middle East, has shrunk by nearly 90% over the past 3 decades; while Bolivia’s Lake Poopó dried out completely in 2015.

As lakes vanish, they leave behind a host of problems: wildlife declines; tourism ebbs away; people are displaced and livelihoods suffer; weather patterns are altered; and water gets scarce, which in turn impacts local agriculture and food supply

Its impacts on human health are also severe. As the water disappears, it exposes the lakebed, or playa – which can quickly dry out to form a layer of sediment and dust, says Michael Cohen from the Pacific Institute, an Oakland, CA-based think tank that focuses on water issues. At the Salton Sea, for instance, more than 18,000 acres of shoreland has been exposed since the early 2000s.

When winds kick up this dust, fine particulate matter “gets airborne and entrained in the air,” says Cohen, who has been studying the Salton Sea for over 2 decades. The particles “can travel for long distances and can get inhaled by people.”

Breathing those particles can inflame the lungs, says Kent Pinkerton, PhD, a professor of pulmonary pathology at the University of California, Davis. “Inflammation is not always bad, it’s a natural process that helps in the clearance of particles.” 

But when there’s too much dust, “you begin to see injury and damage and death of lung cells,” he says. “When particles get down into the deep lung cells that line the alveoli, where we have gas exchange and that’s extremely delicate … it can be extremely problematic.” 

The result is respiratory issues such as asthma, allergies, and chronic sinus infections. Young children, whose immune systems and lungs are still developing, are especially vulnerable. Roughly one in five children have asthma in Imperial County, south of the Salton Sea, which also sees the highest rates of childhood asthma hospitalization and emergency room visits (double the state average).

Left unchecked, the exposed lakebed could release up to 100 tons of dust daily, incurring some $37 billion in associated health care costs by 2047, estimates the Pacific Institute. 

To make matters worse, extremely fine particles can penetrate the lung epithelium and enter the circulatory system, potentially causing cardiovascular problems, says Pinkerton. “This could lead to plaque formation, vascular obstruction, myocardial infarction of the heart, or just simply inflammation of the heart tissue.” Those most at risk include young children, the elderly, and those with other respiratory or heart conditions.

Efforts to address the problems are already underway, largely focusing on suppressing dust from dried-out lake beds. This can take various forms, depending on individual lake makeup and the desired outcomes, says Armistead Russell, PhD, an air pollution expert at the Georgia Institute of Technology who was on an Owens Lake scientific advisory panel. 

At Owens Lake – now the largest source of man-made dust in America, after it was drained in the 1920s to meet the water needs of a growing Los Angeles – the favored approach is shallow flooding, he says. The efforts have reduced air pollution levels in the area over the last 2 decades: In 2018, there were only 8 days when PM10 levels (a measure of inhalable particles 10 micrometers and smaller) exceeded healthy levels, as compared to 49 days in 2002.

A similar solution is now being explored at the Salton Sea. But these dust suppression measures come at a steep cost: the Los Angeles Department of Water and Power had spent an estimated $2.1 billion on Owens Lake as of May 2019, and some 31% of its fresh water supplies on efforts to address the problem. Over at the Salton Sea, a project that aims to capture water and spread it across 4,000 acres of the dry lakebed is projected to cost some $206 million.

Thankfully, there are other options too. These include covering the playa with gravel, plowing the land to roughen its surface, planting special salt-tolerant plants to hold the dust down, and building sand fences or straw bales. “The idea is to minimize or eliminate the dust from these exposed areas,” says Cohen. 

But it isn’t just the size of the airborne particles that’s problematic; it’s their content. Dried-out beds of saline lakes, such as the Salton Sea, tend to be rich in sodium chlorine, magnesium, and other minerals. But they can also contain harmful chemicals.

The water flowing into the Salton Sea, for instance, comes from agricultural runoff. “There’s a lot of pesticides used in the area … and some heavy metals like selenium out there too,” says Cohen. “When these enter your nervous system, they also prompt an immune response.” 

The Aral Sea, between Kazakhstan and Uzbekistan, provides a cautionary tale. Once the world’s fourth largest saline lake, it has shrunk to 25% of its original size over the past 50 years. Its soils are contaminated with heavy metals such as lead and radium, as well as toxic pesticides like DDT leached from nearby cotton fields. This has been linked to numerous problems in the area – above-average rates of anemia, tuberculosis, kidney and liver diseases; lowered life expectancy (51 years, down from 64); and high levels of infertility and reproductive issues.

There, local authorities have tried a different remedy: restoring the lake by reducing water withdrawals from one of its tributaries, the Syr Darya river. They’ve had moderate success.

Physical afflictions aside, vanishing lakes can also affect the mental health of residents living close by. “Younger folk definitely talk about short-term stress, worrying about things like ‘How’s today going to go for me health-wise?’” Loera says of the people she talks to in the Eastern Coachella Valley. 

“But also thinking about this long-term – ‘I want to go to college and do something for my community, but do I really want to stay here and continue to live here?’” she says.

Which is why Loera and her team at the Leadership Counsel, as well as other grassroots organizations such as Comite Civico del Valle and Alianza Coachella Valley, spend time meeting with affected community members, getting them involved in efforts to save nearby lakes, listening to their health concerns, and offering advice on protection measures.

The advice includes taking “safety measures when the air quality is not so good,” says Pinkerton. For example: staying indoors, driving with the air-conditioning on, and wearing a protective N95 mask.

“And just being aware of your body,” he says. “If you find yourself coughing, if your eyes are irritated or watering, if you start feeling fatigued or that your heart is beating fast – these are all symptoms that should tell you: ‘OK, maybe it’s time for me to either put on that mask or go indoors and take it easy.”

Despite the challenges that lie ahead, Loera remains upbeat. “The impressive thing to me is that the community around the Salton Sea is really resilient,” she says. “They’re really collaborative. They see the lake as part of their home.”

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