Dams may cause huge losses of freshwater

LONDON: Dams and irrigation significantly increase evapotranspiration, an effect that increases the loss of freshwater to the atmosphere, thereby reducing the water available for humans, societies and ecosystems on land, a new study has found.

The study shows that dams and irrigation considerably raise the global human consumption of freshwater by increasing evapotranspiration – evaporation and plant transpiration from the Earth’s land and ocean surface to the atmosphere.
“Previously, the global effects of local human activities such as dams had been underestimated. This study shows that, so far, the effects are even greater than those from atmospheric climate change,” said Fernando Jaramillo, postdoc at Stockholm University in Sweden.

The researchers have compiled and analyzed data from 1901 to 2008 for climate, hydrology and water use in one hundred large hydrological basins spread over the world.

Their results raise the previous estimate of the global human freshwater footprint by almost 20 per cent.

The increase in total freshwater loss from the landscape to the atmosphere from human activities is calculated to be around 4,370 cubic kilometres per year, researchers said.

This corresponds to two thirds of the annual flow of the Amazon River, the world’s largest river by discharge, they said.

“The human-caused increase in this loss is like a huge river of freshwater from the landscape to the atmosphere. We have changed so much of the freshwater system without knowing it,” said Gia Destouni, Professor at Stockholm University.

“Our study shows that we have already passed a proposed planetary boundary for freshwater consumption. This is serious, regardless of whether we have crossed a real boundary or if the boundary has been underestimated,” Destouni said.

Alarming research finds humans are using up far more of Earth’s water than previously thought

By Chelsea Harvey

Because of over-management of water resources through such strategies as dams and irrigation projects, humans are wasting vast amounts of water that may be beyond recovery.

Freshwater is one of the planet’s most precious resources — and as the global population grows and our demand for water rises, so does the need to carefully monitor its use and availability. Numerous studies have attempted to calculate the amount of freshwater humans consume globally from year to year. But in a worrying new study in the journal Science, scientists argue that we’ve been significantly underestimating our water footprint — in fact, their research raises the estimate of our global water consumption by nearly 20 percent and suggests that we may have crossed an unsustainable threshold in our water use.

Authors Fernando Jaramillo and Georgia Destouni of Stockholm University focused their research on the effects of flow regulation and irrigation — essentially, building dams and reservoirs for human use — on the water cycle, and found that previous studies have significantly underestimated their influence. Notably, they found a significant increase in water consumption — thousands of cubic kilometers worth — in the latter half of the twentieth century due to human water management.

These practices can have an important influence on what scientists call “evapotranspiration,” which is water that is lost to the atmosphere by either evaporating from the Earth’s surface or being taken up by plants and later released into the air through their leaves. Such factors can add up to a very significant percentage of global water consumption.

While most people think about “water consumption” as referring to the amount of water humans drink or use for industry, water that evaporates into the atmosphere is actually a major component too, said Jaramillo. This handy blog from the World Resources Institute helps explain the concept: Essentially, water consumption refers to any water that is withdrawn and not immediately returned to its original source.

So when water vaporizes and goes into the atmosphere as a result of human actions, such as irrigation or dam-building, it counts as being consumed by humans — even if it comes back down to the Earth at a later point as rain. It’s important to think about consumption in this way: Water that goes into the atmosphere in one place doesn’t necessarily come back down in the same location or in the same amount . And by engaging in practices that cause more water to be lost into the atmosphere than naturally would, humans are interfering with the natural ratio of evapotranspiration to precipitation — in other words, water out versus water in — and that could lead to increases in water shortages down the road.

“A  scientific motivation for this [study] is that we want to understand what is it that drives changes in the freshwater system on land,” said Destouni, the senior author and a professor of hydrology and water resources at Stockholm University. And as the research was conducted, she said, “we started to see that the landscape drivers of change [including human water management] were actually important nearly everywhere.”

There are a variety of ways that human water management techniques can affect how much water is lost to the atmosphere as water vapor, not all of them well understood. Creating reservoirs means there’s a larger surface area of standing water, which can increase evaporation rates. Additionally, irrigation can increase the number of plants in an area, which then draw in more water and release it into the air through their leaves, the process known as transpiration.

The authors decided to determine the global impact of flow regulation and irrigation on the water cycle in order to figure out how much water is being consumed, or lost to the atmosphere, just as a result of these practices. They selected 100 large water basins from around the world to use as a sample, choosing basins “that were more representative and had long-term consistent data on climate and water change and long-term data on water use and land use,” Jaramillo said.

They then used these data to figure out the ratio of evapotranspiration to precipitation — essentially, water out versus water in — between 1901 and 2008. In the past, studies examining the influence of flow regulation and irrigation on the water footprint have used global-scale models, which the authors argue have underestimated the effects on the water cycle. Their study is the first to take a global look at these practices using observed historical data.

“What is really novel and exciting about what Dr. Jaramillo and Destouni did was they took observational data, so measured flow data, on major watersheds, and they were able to detect a signal of a specific human impact,” said Shannon Sterling, an associate professor in the Department of Earth Sciences at Dalhousie University, who was not involved with this paper. “And that’s remarkable.”

After conducting their analysis, the researchers found that between the period from 1901 to 1954 and the period from 1955 to 2008, there was an increase in the average loss of freshwater to the atmosphere of more than 3,500 cubic kilometers, or about 850 cubic miles, of water. Altogether, they estimate that the current level of human freshwater consumption is about 4,370 cubic kilometers, or close to 1,050 cubic miles, per year.

These calculations raise the estimated total human water footprint — that’s all water consumed, freshwater or otherwise — by a whopping 18 percent, bringing it up to about 10,688 cubic kilometers per year.

The authors note that previous papers have proposed a “planetary boundary” of 4,000 cubic kilometers of freshwater consumption per year. Beyond that point, some scientists say that water consumption becomes unsustainable for the Earth’s growing population. Notably, this new study brings the total estimated freshwater consumption above the proposed planetary boundary.

“Whether this actually is a real boundary, of course there’s huge uncertainty related to that,” Destouni said, but added that the study’s results are concerning either way.

“It’s very serious that with such a relatively straightforward thing as water, freshwater — all of us use it all the time — we don’t keep track of what changes we have made and how these changes actually relate to what the planet can withstand,” she said.

Sterling also pointed out that the paper suggests human activities have a particular influence in already water-stressed regions.

“Another important implication of what they found [is that] the biggest reductions in available water from these human activities of dam building and irrigation are in areas that are already arid,” she said. “In these areas, they probably built dams and irrigation to address an existing water stress in the first place.”

The study highlights a critical need for better monitoring of our freshwater use and the ways our management techniques can affect the water cycle, as Jaramillo noted that the current effects of human water management “are even larger and more recognizable than the effects of atmospheric climate change.”

As climate change is predicted to become an increasing threat to water security worldwide, the persistent impacts of human activity on the water cycle will only be compounded by the effects of global warming in the future — making the need for better management techniques an even higher priority.

“That’s another future direction our society needs to take — to go towards greater resource efficiency,” Destouni said. “And if we don’t keep track of how we use water, we cannot reach that efficiency, or even understand what that efficiency means for the future.”

Source: The Washington Post.

Pure Water Gazette Fair Use Statement

Goodpasture Bridge

Built in 1938, the Goodpasture Bridge spans the McKenzie River near the community of Vida in Lane County, Oregon, United States. It is the second longest covered bridge and one of the most photographed covered bridges in the state. The Goodpasture Bridge is listed on the National Register of Historic Places. Around the US there are more covered bridges than one would think. Most have been preserved, at some considerable expense, because of their historical and aesthetic value.

–A thing of beauty is a joy forever.– John Keats. –Model 77 is a thing of beauty and a joy forever. Plus, it has a lifetime warranty.--Pure Water Annie. Take a look.

 Common Uses of Ion Exchange Resins in Water Treatment

Ion exchange resin has been an effective water treatment tool for many years. The most common use, by a long way, is for water softening. Ion exchange resins, however, have many other less frequently used applications. Resins are used to reduce arsenic, nitrates, uranium, perchlorate, and more. They can also “deionize” water completely, removing the full mineral content.

Standard Softener Resin

Cation resins exchange positive ions and Anion resins treat negative ions.

Here’s a chart showing types of resins and many of their uses:
 

Indebted to “Ion Exchange Resins and Their Applications,” Water Technology, Nov. 2015.

Agriculture creates most of the nitrate pollution, but consumers pay most of the cost, whether they drink from public wells or private ones.

The state says that 57 public water systems violated health-based standards for nitrate in 2014. But that statistic does not include hundreds of public systems that have high nitrate in their raw water and never receive a violation because they dilute or treat their water, or replace their wells.

The city of Chippewa Falls has no nitrate violations. But it has been battling high nitrate levels in one of its two wells since the mid-1980s.

Officials have gone to extraordinary efforts to prevent further contamination. They mapped out where the well’s water came from and forbade some groundwater-endangering land use practices in the area. They took a polluting fertilizer company to court. They bought up farmland to protect their so-far-unpolluted second well.

Yet the first well is still polluted, and it may be decades before the water quality improves. Chippewa Falls avoids health violations only by diluting the polluted water with water from the other well.

State Department of Natural Resources drinking water chief Jill Jonas said during a conference last year that since 1999, the state has provided loans to two or three public water utilities each year to address major nitrate contamination, totaling $32.5 million. Loan applications received in 2014 added up to another $4 million.

Per-capita costs vary: Janesville’s $9 million nitrate fix cost $151 per person, but in Mattoon, a town in Shawano County, the cost came to $2,455 per person.

Even drilling a new well is not guaranteed to fix the problem.

“There are some areas of the state where drilling deeper can actually do nothing, and sometimes leads to other contaminants in drinking water,” Jonas said at the conference.

It may cost even more to drill a well in one of more than 100 areas where the state requires minimum depths or special casing because of specific pollution concerns. Six of those areas were created because of nitrate concerns.

Minnesota researchers have tallied up the costs of nitrate pollution on consumers in that state. Their 2008 study found that the cost to buy bottled water to replace tainted tap water cost residents about $190 per person each year.

The average cost of a new deep-aquifer well was $7,200 plus water softener. And water treatment systems like reverse osmosis, distillation or anionic exchange systems cost an average of $800 to install plus $100 a year for maintenance, the study found.

In Wisconsin, private well owners cannot qualify for the state’s Well Compensation Grant Program unless the nitrate level is at least 40 milligrams per liter, well over the health standard of 10 — and, ironically, only if the water is given to livestock.

Source: Post-Crescent Media.

Pure Water Gazette Fair Use Statement

Earth may have kept its own water rather than getting it from asteroids 

by Julia Rosen

Carl Sagan famously dubbed Earth the “pale blue dot” for our planet’s abundant water. But where this water came from—and when it arrived—has been a longstanding debate. Many scientists argue that Earth formed as a dry planet, and gained its water millions of years later through the impact of water-bearing asteroids or comets. But now, scientists say that Earth may have had water from the start, inheriting it directly from the swirling nebula that gave birth to the solar system. If true, the results suggest that water-rich planets may abound in the universe.

“This is a great test of our canonical picture for how Earth got its water, and it suggests that things are not as simple as we first thought,” says Fred Ciesla of the University of Chicago in Illinois, who was not involved in the new study. To understand the origin of Earth’s water, scientists have fingerprinted potential sources, like asteroids and comets, using the ratio of light to heavy hydrogen isotopes. Then, researchers can compare the ratios with those found in water sources on Earth.

However, researchers don’t really know the true hydrogen isotopic composition of Earth’s water, says Lydia Hallis, a planetary scientist at the University of Glasgow in the United Kingdom and lead author of the new study. Scientists have often assumed that the isotopic signature of seawater is close to the true value, but Hallis thinks this has probably changed over geologic time, as Earth preferentially lost light hydrogen atoms to space and gained water from asteroid and comet impacts.

So Hallis and her colleagues went looking for vestiges of the early Earth that might preserve the original hydrogen isotope ratio of the planet. They found them in an unlikely place: Baffin Island in the Canadian Arctic. Here, massive eruptions—fueled by the hot spot that now sits beneath Iceland—produced lava that originated deep in the mantle. So deep, in fact, that this material was probably isolated from the surface for almost all of Earth’s history. The evidence lies in the fact that the lavas, now hardened into basalts, still contain a fair amount of light helium isotopes, which would have escaped to space had the rocks spent much time anywhere near the surface.

In the new study, the researchers report the hydrogen isotope ratios of water trapped in glassy inclusions inside the basalts. The results, published online today in Science, reveal that the inclusions have a much lighter isotopic signature than does the ocean, suggesting that the composition of seawater has indeed evolved over time. Although scientists were aware of processes that could cause an isotopic shift in surface waters, Hallis says, “until we made our measurements, we didn’t know whether that would be a measureable difference or not.”

The new data suggest that the difference is vast. And Hallis suspects that the deepest, most primitive material in the mantle should have an even lighter isotopic composition than the inclusions her team measured. That’s because the rising magma that produced the lavas probably mixed with upper mantle rocks, which have been contaminated with isotopically heavy surface water that got dragged down by subducting slabs of tectonic plates.

So what does all this mean for the origin of Earth’s water? For one, the new data throw a wrench in the conventional story that carbonaceous chondrites—a water-rich variety of asteroid—delivered water to an initially dry Earth after its formation. That scenario has been bolstered by similarities in the isotopic signatures of the asteroids and seawater. But the chondrite signatures are too heavy to explain the deep Earth samples, Hallis says. “The carbonaceous chondrites don’t really work.”

Instead, Hallis and her colleagues propose that Earth’s water came directly from theprotosolar nebula—the cloud of gas and dust that eventually clumped together to form the solar system. Based on measurements of Jupiter and the solar wind, which are thought to preserve the hydrogen isotopic ratio of the protosolar nebula, scientists think nebular water had an extremely light hydrogen isotopic signature—much closer to what the Baffin Island lavas suggest about the deep mantle’s water.

Traditionally, the main objection to this idea has been that the inner portion of the protosolar nebula, where Earth formed, would have been too hot for water to hang around. But Hallis’s team suggests that water floating around in the nebula snuck into our nascent planet by adsorbing to dust particles. They cite previous modeling work suggesting that this mechanism could allow a significant amount of water to survive the brutal temperatures and violent processes by which dust particles coalesced to form planets. Hallis says the discovery of a deep reservoir of material with protosolar isotope ratios supports the idea that the hot, early Earth somehow retained this water.

However, some scientists aren’t ready to abandon the asteroid hypothesis just yet. That’s because, on top of bringing water, they are also believed to have delivered much of Earth’s so-called volatile elements, namely, carbon, nitrogen, and noble gases, says Conel Alexander, a cosmochemist at the Carnegie Institution for Science in Washington, D.C. To explain the abundance of these elements, there would have had to have been enough impacts to also deliver Earth’s water, he says. “That still seems to me the simplest and most attractive explanation.”

Ciesla says that the new results will force scientists to re-evaluate the process of Earth’s formation. Perhaps the team’s adsorption model is correct, or perhaps water came to Earth aboard a kind of asteroid that hasn’t yet been found, or that no longer exists because it all went into making the Earth. “What we have to do is try to understand what fits and what doesn’t,” he says.

However, if Hallis and her colleagues turn out to be right, their hypothesis could have major implications for other planets. In the prevailing model of an initially dry Earth, hydrating the planet seemed like “more of a one-off event,” Hallis says. However, if the planet managed to keep water from the solar nebula before it evaporated away, there’s no reason other planets couldn’t do the same thing. Hallis says that her results could mean that water-rich planets like Earth are not so rare after all.

Science

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San Marcos, TX.  A City Known for its Wonderful Water

 San Marcos Frees Itself from Fluoridation

San Marcos, Texas, home of some of the earth’s most beautiful water,  began artificially fluoridating its drinking water in 1987. In 2015, a major grassroots effort brought that to an end.

A strong coalition of campaigners, including Fluoride Free San Marcos and Texans for Accountable Government, weren’t discouraged by a city council that ignored their calls for an end to the practice.  Instead, the multi-partisan coalition moved forward and collected the 1,600 signatures required to get a resolution amending the city charter on the ballot.  Then another obstacle arose.  Their referendum petition was illegally invalidated by the City Clerk, who even sued Fluoride Free San Marcos and three of its officers to have a judge void the petition and have the campaigners pay the city’s legal expenses.  The judge ruled that the petition was legal, and directed the city to place the question on the ballot.

In a November 2015 election,  voters in San Marcos (pop. 45,000) approved a resolution ending and prohibiting the fluoridation of the public water supply with 61% of the vote.  Voters passed the following language into law: “The City of San Marcos shall not add, or direct or require its agents to add fluoride in the form of hydrofluorosilicic acid, hexafluorosilicic acid, or sodium silicofluoride to the San Marcos municipal water supply.” 

San Marcos joins a growing number of US cities that are rejecting public fluoridation in spite of heavily financed opposition.

Lake Chad Under Threat From Climate Change, Human Activity

by Moki Edwin Kindzeka

A Halloween Horror Story: Waterboarding

Some top American politicians actually endorsed the use of the fearful torture technique known as waterboarding during the dark early days of the “War on Terror”

Waterboarding is a form of water torture in which water is poured over a cloth covering the face and breathing passages of an immobilized captive, causing the individual to experience the sensation of drowning. Waterboarding can cause extreme pain, dry drowning, damage to lungs, brain damage from oxygen deprivation, other physical injuries including broken bones due to struggling against restraints, lasting psychological damage, and death. Adverse physical consequences can manifest themselves months after the event, while psychological effects can last for years.

In the most common method of waterboarding, the captive’s face is covered with cloth or some other thin material, and the subject is immobilized on his/her back at an incline of 10 to 20 degrees. Torturers pour water onto the face over the breathing passages, causing an almost immediate gag reflex and creating a drowning sensation for the captive. Vomitus travels up the esophagus, which may then be inhaled. Victims of waterboarding are at extreme risk of sudden death due to the aspiration of vomitus.

The term water board torture appeared in press reports as early as 1976. In late 2007, it was widely reported that the United States Central Intelligence Agency (CIA) was using waterboarding on extrajudicial prisoners and that the Office of Legal Counsel, Department of Justice, had authorized the procedure among enhanced interrogation techniques. Senator John McCain noted that the United States military hanged Japanese soldiers for waterboarding American prisoners of war during World War II. The CIA confirmed having used waterboarding on three Al-Qaeda suspects in 2002 and 2003.

In August 2002 and March 2003, in its war on terror, the George W. Bush administration issued what became known as the Torture Memos after being leaked in 2004. These legal opinions argued for a narrow definition of torture under US law. The first three were addressed to the CIA, which took them as authority to use the described enhanced interrogation techniques (more generally classified as torture) on detainees classified as enemy combatants.

Why Pure Water Products’ Backwashing Filters Are the Very Best in the World

Gene Franks, Pure Water Products

To start with, we have invented a superior new filter medium that removes all known contaminants from water, never wears out, and is very inexpensive.

We also have created a new filter control valve that lasts for 40 years, runs without electricity, and can be programmed by thought.

Finally, in response to customer demand, we have created a unique space-saving mineral tank that is over twice as large on the inside as it is on the outside.

I really wish I could tell you all of that is true, but, alas, I have to tell you that we mainly use the same old stuff that’s available to everyone else in the industry for making filters. Nevertheless, I can confidently say that our backwashing filters are the best on the market and that it doesn’t worry us that some other internet sites seem to be selling comparable filters at a slightly lower price.

Here are some reasons: 

100% Vortech. We now use Vortech mineral tanks exclusively for all residential-sized filters (up to 13”). Vortech tanks cost more and they are harder to get, but they don’t need gravel underbeds,  and compared with conventional tanks, they save at least 20% of regeneration water used by the filter.  They save water day after day, year after year. We now use Vortech tanks even for dome hole applications (for calcite filters) and bottom drain tanks (for vacation homes that require draining for winter).

We use all Fleck controls. These tried and proven performers are easy to program, easy to maintain, economical to operate. We offer standard timer models, SXT electronic upgrades, and even non-electric manual Fleck units, plus the AIO electronic air-draw control in two control valve styles for problem well water.

We program all control valves before the filter is shipped. Plug it in, set the time of day, and you’re ready to go. If you want to change the programming, it’s easy.

We provide a complete “Setup Sheet” for all filters that lets you know at a glance the type and quantity of the media your filter has, the regeneration time, the backwash and rinse duration, and the drain line flow control size. Plus, we keep this information on file so if you call or email we’ll know exactly what you need for your filter.

We pay shipping. Keep this in mind if you’re comparing prices. Backwashing filters are large and the media that goes in the tank are heavy.

We build filters every day, so we have everything in stock and can normally ship the filter the day you order it. This means also that we always have parts in stock if you need them.

We support installation and service by both email and phone. If you call us, or if your plumber calls us, we’re happy to help.

The most important thing about buying a backwashing filter is getting what is needed for your specific water issue. We offer help in diagnosing water issues and in selecting and sizing equipment. You can contact us by phone or email for help. We offer a dozen different media choices that cover most city or well water issues. We also sell and supply any supporting equipment needed, such as sediment pre-filters, chlorine or aeration pre-treatment, or pH amendment. We also offer free testing to help determine what you need (or don’t need).

What others offer as options, come as standard equipment with our filters. All of our filters come with such standard equipment as a stainless steel bypass valve, drain tubing, pre-installed flow control for regeneration, a media funnel, and a clear-bowl media trap. We’ve just added the media trap as a standard feature to protect your home against media intrusion in home services lines. The bypass, funnel, drain tubing, and media trap when sold as options cost over $100.

 Our Fleck 2510 filters come with either traditional timer or advanced SXT control.