Chlorine bleach was among the most widely available disinfectants, although people had difficulty gauging how much was needed to treat a given amount of water without creating an unpleasant taste or harmful concentrations. The agency therefore supported development of special bottles of dilute bleach—the bottle caps were designed to hold just the right amount of solution to safely treat one jerry can of water. But while this approach continues to be used in many parts of the world, it does not remove suspended material from the water, leaving users with water that is microbe-free but can still look dirty.
Combined with large-particle calcium hypochlorite—essentially, powdered bleach—the result was PUR, a proprietary formulation that Allgood describes as reverse-engineering the municipal water treatment process.
Using PUR is like making a batch of powdered soft drink mix. Each packet of powder is designed to treat 10 liters of water. One simply tears open the packet, pours the powder directly into the water, and stirs. Within a matter of seconds, any floating material will start to flocculate into clumps that sink to the bottom. In no more than five minutes, all of the water is clear, and after standing for about 20 minutes, it will be completely disinfected.
If desired, the solid remnants can be removed with the most basic of filters, such as a simple piece of cloth. Even seasoned observers, including the scientists who initially refined and tested PUR, agree that its action is nothing less than dramatic.
These results were recounted in a paper coauthored by Perry that appeared in the June issue of the Journal of Water and Health.
Other investigators have also published findings from applications of PUR in various settings, ranging from ongoing rural development activities in Kenya and Guatemala to crises like that in Haiti following Tropical Storm Jeanne in September Just a few months after Jeanne struck, various aid agencies purchased 13 million packets of PUR and transported them to parts of Sri Lanka, Indonesia, and the Maldives when they were struck by the great tsunami of December In addition to its humanitarian value in disaster relief, the product is also being marketed as a household commodity in many other parts of the world where large portions of the population lack reliable water treatment.
The pricing of such a good varies widely from one market to another, based on what the local market will be thought to bear. But they know things about brands and brand management and sophisticated marketing and sales techniques that we [can] learn from them. Neither of these organizations present PUR as a single, definitive answer to water treatment under any and all circumstances. Plus, the PUR system requires more components—two containers, a stirrer, a filter—than most other systems.
Norovirus, Giardia and cryptosporidium have also contaminated drinking water supplies in recent years. But the pathogens perhaps highest on the minds of experts today are those that grow in pipes. It poses a microbiological threat with widespread consequences.
Repeated outbreaks at a Quincy, Illinois, veterans home have killed more than a dozen people since Spokespeople with the Illinois veterans home and the Ohio high school note that measures have been taken to reduce the risk of further infections. Photo by T.
When buildings go unused for long periods of time, stagnant water can become a breeding ground for the bacteria. Studies have shown that pesticides pose a serious threat. For example, atrazine has been associated with low birth weight in babies.
Photo by the University of Wisconsin Oshkosh, via Ensia. Neonicotinoids are another example. Excess fertilizer applications on farms also trigger major algal blooms that can contaminate drinking water. Toxins produced by blue-green algae also known as cyanobacteria in Lake Erie fed by runoff from farms in the watershed contaminated the Toledo, Ohio, drinking water system in the summer of Almost half a million people were told to avoid drinking, bathing or cooking with their tap water for a couple of days; people got sick.
It was neither the first nor the last time that such toxins threatened public health. Residents of Carroll Township, Ohio, received a similar warning in September But subsequent tests of the water from his well found high levels of nitrate, which research suggests may be associated with respiratory infections such as RSV.
In addition to drilling a new, deeper well to supply his home, Munsterteiger also has adopted a number of environmental conservation practices in his farming. He uses cover crops and rotates his cows to graze different sections of his land, improving the health of the soil and minimizing runoff, and thereby reducing the nitrate that seeps into the groundwater. He knows that groundwater could become the water that his family members, and his cows, drink.
Minnesota grass-fed beef producer Duane Munsterteiger right adopted a number of water-protecting practices on his farm after his son, Tony, left became ill as a baby with a type of respiratory infection that may be associated with nitrate contamination.
Photo by Tonya Burk for Ensia. Targeting the source of contaminants is a particularly effective way to tackle dirty water. This might mean using cover crops to limit agricultural runoff, as Munsterteiger did, or preventing the discharge of industrial chemicals.
The Clean Water Act, in theory, regulates discharges into U. However, this year the Trump administration issued a new regulation, the Navigable Waters Protection Rule, that narrows the scope of the Clean Water Act by revoking federal protections for millions of miles of streams and millions of acres of wetlands.
The NRDC and other environmental groups have filed a lawsuit to stop the decision. In this regard, too, some states are stepping up to fill in the gaps. Munsterteiger is among farmers participating in the Minnesota Agricultural Water Quality Certification Program, which offers incentives, including financial assistance for practices such as cover cropping, that can reduce the flow of agricultural pollutants into waterways.
Other techniques to prevent contaminants from sullying source water include installing wood chip bioreactors on farms to reduce nitrate pollution. Allaire and other water experts suggest further strategies for reducing drinking water threats, such as increasing funds for the EPA to more quickly identify and regulate contaminants and upgrading water systems infrastructure. Joel Ducoste, a professor of civil, construction and environmental engineering at NC State University, underscores one key challenge: Many of the emerging contaminants of concern for drinking water, such as PFAS, were previously unknown.
It tends to be the small systems that lack the means to install or even maintain operation of the latest treatment technologies. The facility was built but only stayed online for about six months before the community had to abandon it.
Contaminated drinking water disproportionately affects small water systems , which serve predominately rural, low-income communities with relatively high percentages of people of color. The city of Lindsay has just over 13, Kentucky has been a leader in water system consolidation. The state has gone from more than 3, systems in the s to fewer than systems in Just a few miles down the road from El Rancho is Tooleville.
For a long time, the small town dealt with high levels of nitrate. Benjamin Cuevas, a resident of Tooleville, says that he and his wife, Yolanda Cuevas, have been careful to make sure their three daughters and two grandchildren do not consume any of the water out of their taps.
Yolanda Cuevas rinses the kids down with bottled water after they shower. And she insists that they also use bottled water to brush their teeth. The Cuevases and Ramos have different problems, but they share a lot of same concerns — and aspirations. Message to Candidates: Focus on water quality in Great Lakes states. Covering about 70 percent of the earth , surface water is what fills our oceans, lakes, rivers, and all those other blue bits on the world map.
Surface water from freshwater sources that is, from sources other than the ocean accounts for more than 60 percent of the water delivered to American homes. But a significant pool of that water is in peril.
According to the most recent surveys on national water quality from the U. Environmental Protection Agency, nearly half of our rivers and streams and more than one-third of our lakes are polluted and unfit for swimming, fishing, and drinking.
Nutrient pollution , which includes nitrates and phosphates, is the leading type of contamination in these freshwater sources.
While plants and animals need these nutrients to grow, they have become a major pollutant due to farm waste and fertilizer runoff. Municipal and industrial waste discharges contribute their fair share of toxins as well. Eighty percent of ocean pollution also called marine pollution originates on land—whether along the coast or far inland. Contaminants such as chemicals, nutrients, and heavy metals are carried from farms, factories, and cities by streams and rivers into our bays and estuaries; from there they travel out to sea.
Meanwhile, marine debris— particularly plastic —is blown in by the wind or washed in via storm drains and sewers. Our seas are also sometimes spoiled by oil spills and leaks— big and small —and are consistently soaking up carbon pollution from the air. The ocean absorbs as much as a quarter of man-made carbon emissions. Examples include wastewater also called effluent discharged legally or illegally by a manufacturer, oil refinery, or wastewater treatment facility, as well as contamination from leaking septic systems, chemical and oil spills, and illegal dumping.
The EPA regulates point source pollution by establishing limits on what can be discharged by a facility directly into a body of water. While point source pollution originates from a specific place, it can affect miles of waterways and ocean. Nonpoint source pollution is contamination derived from diffuse sources. These may include agricultural or stormwater runoff or debris blown into waterways from land. Nonpoint source pollution is the leading cause of water pollution in U.
Transboundary pollution is the result of contaminated water from one country spilling into the waters of another. Contamination can result from a disaster—like an oil spill—or the slow, downriver creep of industrial, agricultural, or municipal discharge. Around the world, agriculture is the leading cause of water degradation. In the United States, agricultural pollution is the top source of contamination in rivers and streams, the second-biggest source in wetlands, and the third main source in lakes.
Every time it rains, fertilizers, pesticides, and animal waste from farms and livestock operations wash nutrients and pathogens—such bacteria and viruses—into our waterways. Nutrient pollution , caused by excess nitrogen and phosphorus in water or air, is the number-one threat to water quality worldwide and can cause algal blooms , a toxic soup of blue-green algae that can be harmful to people and wildlife. Used water is wastewater. It comes from our sinks, showers, and toilets think sewage and from commercial, industrial, and agricultural activities think metals, solvents, and toxic sludge.
The term also includes stormwater runoff , which occurs when rainfall carries road salts, oil, grease, chemicals, and debris from impermeable surfaces into our waterways. In the United States, wastewater treatment facilities process about 34 billion gallons of wastewater per day.
These facilities reduce the amount of pollutants such as pathogens, phosphorus, and nitrogen in sewage, as well as heavy metals and toxic chemicals in industrial waste, before discharging the treated waters back into waterways.
Big spills may dominate headlines, but consumers account for the vast majority of oil pollution in our seas, including oil and gasoline that drips from millions of cars and trucks every day. Moreover, nearly half of the estimated 1 million tons of oil that makes its way into marine environments each year comes not from tanker spills but from land-based sources such as factories, farms, and cities.
At sea, tanker spills account for about 10 percent of the oil in waters around the world, while regular operations of the shipping industry—through both legal and illegal discharges—contribute about one-third.
Oil is also naturally released from under the ocean floor through fractures known as seeps. Radioactive waste is any pollution that emits radiation beyond what is naturally released by the environment.
Radioactive waste can persist in the environment for thousands of years, making disposal a major challenge. Accidentally released or improperly disposed of contaminants threaten groundwater, surface water, and marine resources.
To put it bluntly: Water pollution kills. In fact, it caused 1.
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