Tag Archives: agriculture and water pollution

The Shameful Mismanagement of the Murray-Darling River: Australia

Millions of fish have died in the Darling River near his town, Menindee, in outback New South Wales, Australia in March 2023. After days under the sun, their bodies had started to “break up…transforming the river that locals rely on for drinking and showering into an ecological wasteland. Authorities have said the mass death was caused by a lack of oxygen in the water, called hypoxia, a result of recent floods and a heat wave. But furious locals say the true root of the problem is the overuse of Australia’s biggest and most vital river system.

The disaster is the latest episode in a long-running battle over the Murray Darling Basin, a vast network of lakes and rivers stretching across four states in eastern Australia, which sustains much of the country’s agriculture and dozens of communities along its banks. In an arid country where social, economic and environmental interests clash whenever water runs scarce, the issue has pitted states against each other, and riverside communities against farms upstream.

The 2019 fish deaths happened during a drought and the 2023 fish deaths happened after a flood, said Richard Kingsford, the director of the Center for Ecosystem Science at the University of New South Wales. But, he said, the long-term causes were the same both times: “There’s not enough water in the river, and the whole system is engineered so that escape routes are closed.” Over-extraction means parts of the river run dry more often, he said, and the small and medium-sized floods that used to periodically clear away organic debris have all but disappeared. That means when a big flood hits, that debris is all swept into the river, where it breaks down and deoxygenates the water. That, combined with the construction of weirs that have prevented the fish from swimming to better-oxygenated water, has made this disaster worse, he said….

The New South Wales fisheries and water management bodies, by contrast, both attribute the disaster to weather-related causes…

After many of the fish had already sunk to the bottom of the river, the cleanup started with workers in small boats removing floating carcasses with hand-held nets. Authorities said this will be followed by machinery that will drag nets through the river to scoop up sunken fish….

Excerpts from Yan Zhuang, A River Choking on Fish Corpses, and a Community Full of Anger, NYT, Mar. 24, 2023

How to Find the True Cost of Water

At current rates of consumption, the demand for water worldwide will be 40% greater than its supply by 2030, according to the UN. Portfolio managers are realizing that physical, reputational and regulatory water risk could hurt their investments, particularly in thirsty industries such as food, mining, textiles and utilities.

One worry is that shocks to supply could drown or dry out a company’s assets. In recent years Coca-Cola has been forced to close plants in India because of drought. In 2019 floods in America’s Midwest caused disruptions at the facilities of two food giants, Cargill and Tyson Foods. A survey by CDP, a non-profit firm, found that 783 big listed companies had faced a total of $40bn of water-related losses in 2018.

Another concern is that the price a company pays for water could rocket. The market price of water does not reflect the environmental and social costs of using it. Government subsidies also mean that companies often do not pay for its true cost. As aquifers are depleted, though, subsidies could become more costly and unpopular, forcing governments to retract them. S&P Global Trucost, a data provider, reckons that if Fortune 500 companies paid the true cost of water, based on estimates of scarcity, rather than current prices, their profit margins would shrink by a tenth. Margins for food, drink and tobacco firms would fall by three-quarters.

Disclosures of water risk are even patchier than those of greenhouse-gas emissions…Established names like Bloomberg and S&P Global are plugging the gap, as are startups. The result is that investors can approach management armed with data rather than questions. “We are getting rid of the black box that companies hide in.” 

Ceres, a non-profit firm, scores businesses on everything from direct water management to risks in the supply chain. Those seeking more detail can use visual tools, such as Bloomberg’s “maps” function, which plots a company’s facilities over a heat map based on water stress. (California is the same color as swathes of sub-Saharan Africa; far-eastern Russia looks a lot like western Europe.) Firms like Aquantix go further, and try to predict the financial cost of water risk.

The accuracy of such forecasts is not yet proven. For Andrew Mason of Aberdeen Standard Investments, though, they are still useful. They show companies that investors care about water risk and encourage them to share data. “This is where carbon was ten or 15 years ago,” he says.

Excerpt from An expanding pool: Investors start to pay attention to water risk, Economist, Jan. 9, 2021

The Fight Against Toxic Algae

Signs posted around the Grand Lake, Ohio read: “Danger: Avoid all contact with the water.”  When dangerously high levels of toxins from blue-green algae in Grand Lake, Ohiio were publicized in 2009, many residents and tourists stopped using the 13,000-acre lake in northwest Ohio. Hotel revenue and home values sank for several years as algae bloomed in the state’s largest inland lake.

Greenish water still laps at Grand Lake’s shores, but recent water samples show that the amount of algae-feeding nutrients entering the lake is down significantly. State, federal and private donations covered more than $10 million in projects aimed at improving water quality. More people are boating on the lake again. Grand Lake could now serve as an example for communities with algae problems across the nation, experts say.

Algal blooms are on the rise, from Lake Erie to the Florida Everglades. In August 2019, the Environmental Protection Agency listed algae-related beach closures or health advisories in 23 states, and it said other blooms may not have been reported. In 2010, the EPA found that 20% of 50,000 lakes surveyed had been affected by phosphorous and nitrogen pollution, which feeds algae.e  Cleaning up bodies of water choked with toxic algae has proved difficult. The project to repair Grand Lake, once one of the most polluted by algae in the nation, is one of the clearest successes. It shows cleanup is possible, but also expensive and time-consuming.

“It’s not restored yet, but it’s on the road to recovery,” said Stephen Jacquemin, an associate professor of biology at Wright State University-Lake Campus in Celina.  Beginning in 2012, wetlands areas were built around the lake, which was hand dug in the 1830s. The thick stands of bulrushes and other plants have reduced phosphorous and nitrogen levels in water entering the wetlands before reaching the lake by as much as 90%, Dr. Jacquemin said.  Three wetland areas, which cost a total of about $6 million to build, are constructed as a series of interconnected pools that allow particulates to settle out and plants and microbes to remove nutrients.

Areal View of Artificial Wetlands, Great Lake Ohio

 The state’s Department of Natural Resources has also dredged the lake bottom to remove nutrient-loaded sediment, and tried to clean up one of Grand Lake’s beaches near St. Marys by building a rock jetty and installing aerators and a curtain to filter water. Recent water tests there showed levels below 6 parts per billion of the toxin microcystin, under Ohio’s threshold of 20 parts per billion for avoiding contact with water.

As Green Algae Forces Beaches to Close, Ohio Lake Offers Hope, WSJ, Sept. 18, 2019