Ceramic filter makes water treatment easy

The technology sounds simple: fire a ceramic pot, perhaps coat it with a fine layer of silver, and let the water percolate through. In regions where water carries millions of microbes, this relatively inexpensive treatment method has its attractions. For about a decade, the nonprofit organization Potters for Peace has been teaching communities to manufacture their ceramic water filters, which retail for $5–15. Although they have been used widely from Nicaragua to Thailand, no scientific data have been published to prove their efficacy or to show how these ceramic filters work.

Now researchers from the University of Virginia report that clay water filters from Mexico and the U.S. can remove more than 98% of the test organism E. coli. With an added layer of silver, the filters remove all E. coli. "Without the silver—just the ceramic filter—it seems like it works well, but adding the silver further improves the performance," says coauthor James Smith.

"Until this report, there have been very little data on how [the filters] work and what the specific mechanisms are," says Kara Nelson, an environmental engineer who studies a variety of low-cost point-of-use water treatments at the University of California Berkeley. "Without an understanding of the fundamental mechanisms behind [a technology], we have to take a black-box approach," she says. "That's not efficient. There are so many different pathogens, so many environmental conditions, so many different things that could be in water."

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A lush oasis could go dry.

This desert oasis east of Los Angeles sold itself for decades on water and all the luxury it brings: strings of emerald golf courses, lush resorts and manicured neighborhoods with sparkling pools.

Now, the region that water built suddenly finds itself on shifting ground and in danger of drying up. Parts of the Coachella Valley have sunk more than a foot in a decade as groundwater was sucked up to feed a thirsty economy.

A study released this week has left officials scrambling to keep the tap on without jeopardizing more than 120 world-class golf resorts - among them PGA West, Bermuda Dunes Country Club and Mission Hills - or slowing a population that has ballooned by 25 percent in just five years.

"We have a problem, and we have to deal with it," said Steven Robbins, chief engineer for the Coachella Valley Water District. "But our goal is to not have water be a constraint to growth. We don't want to be the ones to say 'yea' or 'nay' to growth."

Water officials are pursuing a range of solutions to ease the pressure on the aquifer, from a giant pipeline to import water for golf courses to giving away timers to regulate home sprinklers.

Though there hasn't been any damage, there are fears that if more isn't done, the uneven turf eventually could fracture sewer lines, crack roads and crumble foundations, costing taxpayers millions of dollars in repairs.

from the Philadelphia Inquirer

U.S. Corn Boom Has Downside for Gulf

Because of rising demand for ethanol, American farmers are growing more corn than at any time since the Depression. And sea life in the Gulf of Mexico is paying the price.

The nation's corn crop is fertilized with millions of pounds of nitrogen-based fertilizer. And when that nitrogen runs off fields in Corn Belt states, it makes its way to the Mississippi River and eventually pours into the Gulf, where it contributes to a growing "dead zone" - a 7,900-square-mile patch so depleted of oxygen that fish, crabs and shrimp suffocate.

The dead zone was discovered in 1985 and has grown fairly steadily since then, forcing fishermen to venture farther and farther out to sea to find their catch. For decades, fertilizer has been considered the prime cause of the lifeless spot.

With demand for corn booming, some researchers fear the dead zone will expand rapidly, with devastating consequences.

"We might be coming close to a tipping point," said Matt Rota, director of the water resources program for the New Orleans-based Gulf Restoration Network, an environmental group. "The ecosystem might change or collapse as opposed to being just impacted."

Environmentalists had hoped to cut nitrogen runoff by encouraging farmers to apply less fertilizer and establish buffers along waterways. But the demand for the corn-based fuel additive ethanol has driven up the price for the crop, which is selling for about $4 per bushel, up from a little more than $2 in 2002.

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All About: Water and Health

The next time you fall sick and someone suggests it's because of something in the water, they could be right. According to the World Bank, 88 percent of all diseases are caused by unsafe drinking water, inadequate sanitation and poor hygiene.

The number are daunting. Annually, water-related problems are responsible for:

4 billion cases of diarrhea, resulting in the deaths of more than 6 million children.

300 million malaria sufferers;

200 million schistosomiasis sufferers;

6 million people who have been struck blind by trachoma;

and 500 million people who are currently at risk of contracting it, the World Bank says.

The U.N. also suggests that unsanitary water is to thank for 1.5 million cases of hepatitis A (and 133 million cases of intestinal worms).

At any one point in time, 50 percent of all people in the developing world will be in hospital suffering from one or more water-related diseases. Most will be children, water-related diseases being the second biggest killer of children worldwide (after acute respiratory diseases like Tuberculosis), according to Water Aid. (Diarrhea alone has killed more children in 10 years than all the people killed in wartime since World War 2, according to UNICEF).

Humans have become walking, talking carriers of diseases, thanks to poor sanitation and undrinkable water. Take one gram of human excrement these days, UNICEF says, and you could find around 10 million viruses, 1 million bacteria, 1,000 parasite cysts and 100 parasite eggs.

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In China, Farming Fish in Toxic Waters

Here in southern China, beneath the looming mountains of Fujian Province, lie dozens of enormous ponds filled with murky brown water and teeming with eels, shrimp and tilapia, much of it destined for markets in Japan and the West.

Fuqing is one of the centers of a booming industry that over two decades has transformed this country into the biggest producer and exporter of seafood in the world, and the fastest-growing supplier to the United States.

But that growth is threatened by the two most glaring environmental weaknesses in China: acute water shortages and water supplies contaminated by sewage, industrial waste and agricultural runoff that includes pesticides. The fish farms, in turn, are discharging wastewater that further pollutes the water supply.

“Our waters here are filthy,” said Ye Chao, an eel and shrimp farmer who has 20 giant ponds in western Fuqing. “There are simply too many aquaculture farms in this area. They’re all discharging water here, fouling up other farms.”

Farmers have coped with the toxic waters by mixing illegal veterinary drugs and pesticides into fish feed, which helps keep their stocks alive yet leaves poisonous and carcinogenic residues in seafood, posing health threats to consumers.

Environmental degradation, in other words, has become a food safety problem, and scientists say the long-term risks of consuming contaminated seafood could lead to higher rates of cancer and liver disease and other afflictions.

No one is more vulnerable to these health risks than the Chinese, because most of the seafood in China stays at home. But foreign importers are also worried. In recent years, the European Union and Japan have imposed temporary bans on Chinese seafood because of illegal drug residues. The United States blocked imports of several types of fish this year after inspectors detected traces of illegal drugs linked to cancer.

More from the New York Times

Colorado River water deal is reached

The federal government Thursday ushered in a new era of shortage on the Colorado River, adopting a blueprint for how it will tighten the spigot on the West's most important water source.

The guidelines, more than two years in the making, come in the eighth year of the worst drought in the century-long historic record of the Colorado River, which supplies water to 25 million people and 1 million acres of farmland.

Federal water managers say a shortage could be declared as early as 2010, allowing the Department of the Interior to reduce water deliveries to Arizona and Nevada, two of the seven states that have sparred over the waterway for decades. California, which has the biggest water allocation and senior rights in the lower basin, would not be affected.

The drought has left Lake Powell and Lake Mead, the river's two mammoth reservoirs, half-empty, their receding shorelines marked by a wide band of bleached rocks that a decade ago were under water. Without some wet years, Lake Mead may never refill, federal hydrologists say.

"We have had good news and bad news," Interior Secretary Dirk Kempthorne said in a speech before signing the document at the Colorado River Water Users Assn. meeting at Caesars Palace. The bad news, he said, is that the drought shows "no sign of ending."

Scientists also predict that climate change will worsen Western drought patterns and reduce Colorado River flows by increasing evaporation and decreasing snowfall. One study released this year warned that global warming could thrust the Southwest into a state of permanent drought by 2050.

"Runoff in five of the seven Colorado River basin states is projected to decline by more than 15% during the 21st century," Kempthorne said.

Against that backdrop, the basin states of Wyoming, Utah, Colorado, Nevada, New Mexico, Arizona and California began negotiations in 2005 on a blueprint for water shortages.

Their plans formed the basis of the document signed by Kempthorne, who called it "an agreement to share adversity" and a landmark in the tangled history of Colorado River management.

More from the Los Angeles Times

Trouble in Them Thar Hills

One of the United States' most beautiful landmarks may soon have to change its name. Glacier National Park in Montana, which once boasted 150 of the spectacular rivers of ice, is now down to 25, and the most recent data show that the remainder "may be gone in our lifetimes," an ecologist said here yesterday at a meeting of the American Geophysical Union. Other than the aesthetic loss, the disappearance of glaciers across the American West could cause huge problems for a regional population that is 85% dependent on mountain water and already coping with shortages.

Compared to Earth's more permanent polar ice caps, mountain glaciers are transient. The glaciers of the American West, for example, formed about 8000 years ago--several millennia after the end of the last ice age--during a prolonged cold period. Since then, they have become a scenic fixture of the landscape, drawing millions of visitors a year, and also act as a source of freshwater, for ecosystems as well as humans, during their annual spring and summer runoffs.

The problem now is that "all of the glaciers are disappearing," said ecologist Daniel Fagre of the U.S. Geological Survey's Northern Rocky Mountain Science Center, located in Glacier National Park. The latest surveys conducted by the organization show that the glaciers are, on average, 1.7 meters thinner each year--a decline much more rapid than expected. One of the hardest hit is the Grinnell Glacier, which had ice as much as 300 meters thick when it was discovered in the 19th century. Now that ice is completely gone in some places, exposing soils that have not seen daylight in thousands of years. Bighorn sheep are grazing in areas that until recently were overlain by ice, Fagre said.

Warmer temperatures are only part of the problem, explained geographer Thomas Painter of the University of Utah, Salt Lake City, who presented his own research on snowpack in the West at the meeting. Also contributing is carbon black, known more commonly as soot, which continually rains down on the glaciers but tends to concentrate on the surface of the ice. By the calculations of his research team, Painter said, soot increases heat absorption from the sun's rays by 43%. That provides "yet another reason" to limit carbon black from industrial emissions, says climatologist Claire Parkinson of NASA's Goddard Space Flight Center in Greenbelt, Maryland.

More from Science

China's Mother River Under Threat

The Yellow River snakes through northern China for more than 3,000 miles and is known as the country's mother river. Thousands of years ago, Chinese civilization grew up along its banks.

But it's also known by another name: China's sorrow. Over the centuries, its floodwaters have claimed millions of Chinese lives.

Now, though, the problem has reversed. For three years in the 1990s, the Yellow River — which 140 million people depend on for water — actually dried up before it reached the sea, due to overuse. And pollution on the river has reached horrific levels.

The river begins its journey across the country high on the Tibetan plateau in western China's Qinghai Province. Amid silence and pristine beauty, the river flows out of two crystal clear lakes 15,000 feet above sea level, surrounded by snowcapped mountains and grasslands. The blue sky and mountain snow are dazzling, as is the wildlife here: deer, wolves, foxes and eagles.

The water — bright and clear — defies the name of the river it is becoming as it begins to flow out of the lakes.

But a closer look at the flat grasslands between the lakes and the mountains reveals dark hollows that scar the landscape. There used to be some 4,000 small, shallow lakes in the area. Now, three-quarters of them are dry.In fact, the whole ecosystem at the river's source is in trouble, and scientists are worried. They say there hasn't been enough rain, and so the soil is increasingly dry and barren.

Rising temperatures associated with climate change are melting the glaciers and also thawing the permafrost, so water is being absorbed into the soil and not reaching the river, scientists say.

And Tibetan nomads who have roamed these parts for centuries have overgrazed the grasslands with their animals, according to the scientists, leading to severe soil erosion that also diminishes the flow of water to the river.

Focusing on this last issue, the government has started to force the Tibetans to give up herding and their nomadic way of life — and to settle in one place.

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Western States Agree to Water-Sharing Pact

Facing the worst drought in a century and the prospect that climate change could yield long-term changes on the Colorado River, the lifeline for several Western states, federal officials have reached a new pact with the states on how to allocate water if the river runs short.

State and federal officials praised the agreement as a landmark akin to the Colorado River Compact of 1922, which first outlined how much water the seven states served by the river — California, Nevada, Arizona, Colorado, Utah, New Mexico and Wyoming — would receive annually.

The new accord, outlined by federal officials in a telephone news conference Friday, spells out how three downriver states — California, Arizona and Nevada — will share the impact of water shortages. It puts in place new measures to encourage conservation and manage the two primary reservoirs, Lake Mead and Lake Powell, which have gone from nearly full to just about half-empty since 1999.

The accord is expected to forestall litigation that was likely to have arisen as fast-growing states jockey for the best way to keep the water flowing to their residents and businesses in increasingly dry times. It would be in effect through 2026 and could be revised during that time.

Some environmental groups said the pact did not go far enough to encourage conservation and discourage growth. But federal officials said they took the best of several proposals by the states, environmental organizations and others and emphasized the importance of all seven states agreeing with the result.

“I think for the first time in 85 years we are on the same page,” said Herb Guenther, the director of water resources in Arizona, which had initially balked at some terms of the agreement and was threatening legal action over it.

But with water levels in reservoirs dropping, a record eight-year drought, the prospect that climate change could bring more dry spells and new scientific analyses suggesting the West could be drier than has been traditionally believed, the states were pushed to act.

More from the New York Times

High Weedkiller Levels Found in River Checks

Atrazine, the second most widely used weedkiller in the country, is showing up in some streams and rivers at levels high enough to potentially harm amphibians, fish and aquatic ecosystems, according to the findings of an extensive Environmental Protection Agency database that has not been made public.

The analysis -- conducted by the chemical's manufacturer, Syngenta Crop Protection -- suggests that atrazine has entered streams and rivers in the Midwest at a rate that could harm those ecosystems, several scientific experts said. In two Missouri watersheds, the level of atrazine spiked to reach a "level of concern" in both 2004 and 2005, according to the EPA, and an Indiana watershed exceeded the threshold in 2005.

Much of the data on atrazine levels has remained private because Syngenta's survey of 40 U.S. watersheds was done in connection with the EPA's 2006 decision to renew its approval of the pesticide. The Washington Post obtained the documents from the Natural Resources News Service, a District-based nonprofit group focused on environmental issues.

Atrazine has been linked to sexual abnormalities in frogs and fish in several scientific studies, but the EPA ruled in September that the evidence was not sufficiently compelling to restrict use of the pesticide. EPA spokeswoman Jennifer Wood said the agency "has concluded that atrazine does not adversely affect gonadal development in frogs, based on a thorough review of 19 laboratory and field studies, including studies submitted by [Syngenta] and others in the public literature."

The pesticide is popular among corn and sorghum farmers despite the controversy because it is inexpensive and blocks photosynthesis, thus killing plants to which it is applied.

"It works and it's inexpensive, and that's what farmers love," said Tim Pastoor, head of toxicology at Syngenta. "It's magic for them. It's like the aspirin of crop protection."

EPA officials and independent experts spent last week in meetings in Arlington, debating the "ecological significance" of atrazine water contamination, according to agency documents. The results of the deliberations -- the monitoring data was plugged into computer models to estimate the effects on ecosystems -- will be published in several weeks and will help determine how EPA officials regulate the pesticide in the future.

more from the Washington Post

Troubled tributary

It looked like just another beautiful day on the water as Bill Dennison and his crew of biologists pushed off from their pier at the Horn Point Laboratory and sailed toward the mouth of the Choptank River. The sun glistened on the waves. In the distance, craggy, tree-lined peninsulas carved the river into jagged coves that have long been home to crabs and rockfish.

But there were hardly any fishing boats. In fact, hardly anyone was on the river at all.
It soon became clear why. The researchers passed large patches of brownish-white foam - so-called "mahogany tides" where the water is so thick with algae that no light can get through. The tides have killed many of the river's once-lush grass beds, depriving crabs of their nursery habitat. The algae have also led to low oxygen levels that have forced the crabs and fish to go elsewhere.

The signs are everywhere: The Choptank is in trouble.

This Eastern Shore river, which meanders along farm fields and past picturesque towns on its way to the Chesapeake Bay, recently ranked as the second-most polluted river in the state. Only the Patapsco, which runs through Baltimore City, was worse.

Dennison, a vice president at the University of Maryland Center for Environmental Science, oversaw the rankings. It was with no pleasure that he gave the Choptank a D-minus.

"It has visibly changed," Dennison said, "and now the data support that it has functionally changed."

In the nearly 25 years since Maryland, Pennsylvania and Virginia signed a historic agreement pledging to clean up the Chesapeake Bay and its rivers, the Choptank has not only failed to improve, but, by many measures, it has also gotten worse. The river is being choked by pollution from the region's farms and many new housing developments.

more from the Baltimore Sun

The dirty Don

Encased in concrete walls for much of its length, poisoned by runoff from sewers and streets, the turbid Don is Ontario's dirtiest river, and one of the worst in Canada.

The river, which flows a mere 38 kilometres from its nearly pristine source on the Oak Ridges Moraine to its garbage-choked, oil-slicked mouth on Lake Ontario, scored a lowly 34.8, on a scale of zero to 100, in an Environment Canada calculation of water quality, released yesterday.

The main problem is a glut of phosphorous, chlorine and ammonia, mainly from human and animal sewage, fertilizer and road salt.

The Humber, Credit, and others in the region fared better in the ranking of 395 rivers across the country, based on averages of seven contaminants from 2003 to 2005.

The absolute worst, anywhere, are Quebec's Yamaska and Bayonne rivers, despoiled by pollution from pulp mills and languishing at around 27 points.

The figures are contained in the third annual Canadian Environmental Sustainability Index, which also shows southern Ontario has some of Canada's worst air quality. Environment Canada compiles the index from water sampling done by other government agencies.

The main question is whether the Don is improving.

"The Don is symbolic of a lot of the problems with environmental policy in Ontario," said Mark Mattsen, president of Lake Ontario Waterkeepers. "The river is hardly a river at all. It's an embarrassment."

more from the Toronto Star

Harnessing the Power of the Gulf Stream

In Washington recently, Secretary of the Interior Dirk Kempthorne made an announcement that clears the way for a new and largely untapped renewable energy resource — the oceans.

He announced regulations that would "guide the use of wind, wave and current resources on the 1.8 billion acres of Outer Continental Shelf on the coasts of the Atlantic, Pacific and Gulf Coast."

In South Florida, researchers are already working to harness the power of one of the ocean's most energy-dense currents — the Gulf Stream.

The Center of Excellence in Ocean Energy Technology is only a little more than a year old, but it's in a great location. It's just off the beach and, as director Rick Driscoll points out on a map, it is just 15 miles from the Gulf Stream.

"This is actually the closest location of any place on the planet of a major ocean current by a load center that needs the power now," he says. "We have no place to build power plants and yet we're growing. Florida is growing by a thousand people a day."

Driscoll's answer: underwater turbines moored in the heart of the Gulf Stream. He believes that ultimately, the current — which flows at 8 billion gallons per minute — could yield as much energy as several nuclear plants, providing one-third of Florida's power.

More from NPR

A Warning About East Coast Tsunamis

The risk is low. But the consequences could be high, with deadly waves striking the coastal communities of Long Island, Connecticut and New Jersey and killing thousands of people.

Today, the federal government is announcing that it has completed the mid-Atlantic region’s risk assessments for the killer mounds of water known as tsunamis, or tidal waves.

Scientists have long considered the West Coast of North America as the side of the continent most likely to suffer earthquakes and the undersea disturbances that raise tsunamis. But in recent years, with a growing appreciation of the diverse origins of the giant waves and their potential for havoc, experts have found new reasons for vigilance along the East Coast.

“Tsunamis are a real threat,” said Lisa Taylor, an official at the National Oceanic and Atmospheric Administration, which is conducting the assessments for coastal regions that are considered at risk. A main factor is whether the land rises sharply or gently, the latter being more prone to poundings from unexpectedly high waves.

The project creates elevation maps of coastal lands and adjacent seafloors, helping scientists better forecast the areas that a tsunami would flood. The giant waves can arise hundreds of miles away, in theory giving emergency planners hours to send people to higher ground.

Part of the new analysis focuses on the easternmost area of Long Island, including East Hampton and Southampton, and the southeastern coast of Connecticut, including Mystic and Old Saybrook. The analysis also evaluates the risk for Atlantic City.

A recent federal study found that a seaquake in a deep trench off Puerto Rico could raise a tsunami that would travel for nearly five hours on the ocean’s surface before crashing into Montauk, on the southeastern tip of Long Island.

Since 2006, scientists at the oceanic agency have digitally created elevation models for 20 coastal communities, and they expect to make more than 50 others. Analyses are planned for Miami and Palm Beach in Florida; Boston, Cape Cod and Nantucket in Massachusetts; and New York City.

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