Death Toll of Children from Water-Related Ailments

Water News in a Nutshell.

 

In a Nutshell:  Although fewer children are dying than before from diarrheal diseases linked to unsafe water, poor sanitation and hygiene, the numbers are horrifying.  Sometimes we become numb to large numbers, but when you put the numbers in schoolbus loads of children under 5 it drives the point home.
If 90 school buses filled with kindergartners were to crash every day, with no survivors, the world would take notice. But this is precisely what happens every single day because of poor water, sanitation and hygiene.–Sanjay Wijesekera, Head of UNICEF’s water, sanitation and hygiene program.

Nearly 2,000 children around the globe, under the age of five, die every day from diarrheal diseases linked to unsafe water, poor sanitation and hygiene, with 24 per cent of the deaths occurring in India alone, a UN report has warned.

Globally, an estimated 2,000 children under the age of five die every day from diarrhoeal diseases and of these some 1,800 deaths are linked to water, sanitation and hygiene, according to the report.

Measuring dead children by the schoolbus load drives home the point.

The United Nations Children’s Fund (UNICEF) child mortality data reveals that about half of under-five deaths occur in only five countries: India, Nigeria, Democratic Republic of the Congo (DRC), Pakistan and China.Two countries – India (24 per cent) and Nigeria (11 per cent) – together account for more than a third of all under-five years deaths. These same countries also have significant populations without improved water and sanitation.

Of the 783 million people worldwide without improved drinking water, there are 119 million in China; 97 million in India; 66 million in Nigeria; 36 million in DRC; and 15 million in Pakistan.

The figures for sanitation are even bleaker. Those without improved sanitation in these countries are: India 814 million; China 477 million; Nigeria 109 million; Pakistan 91 million; and DRC 50 million.

As the world celebrates World Water Day today, UNICEF has urged governments, civil society and ordinary citizens to remember that behind the statistics are the faces of children.

Despite a burgeoning global population, these deaths have come down significantly over the last decade, from 1.2 million per year in 2000 to about 760,000 a year in 2011. However, UNICEF said that is still too many.

“Sometimes we focus so much on the big numbers, that we fail to see the human tragedies that underlie each statistic,” said Sanjay Wijesekera, global head of UNICEF’s water, sanitation and hygiene programme.

“If 90 school buses filled with kindergartners were to crash every day, with no survivors, the world would take notice. But this is precisely what happens every single day because of poor water, sanitation and hygiene,” Wijesekera said in a statement.

“The numbers can be numbing, but they represent real lives, of real children. Every child is important. Every child has the right to health, the right to survive, the right to a future that is as good as we can make it,” said Wijesekera.

Wijesekera said the progress already made since 1990 shows that with the political will, with investment, with a focus on equity and on reaching the hardest to reach, every child should be able to get access to improved drinking water and sanitation, perhaps within a generation.

Source: Hindu Business Line.

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Does Fracking Really Deplete Water Supplies?

Jesse Jenkins writing in the Wall Street Journal takes an in depth look at the question in the title.  Since what we hear about fracking are the big round numbers like four million gallons of water per well and billions upon billions of gallons consumed per year, it is easy to look at hydraulic fracturing for the purpose of energy production as an environmental disaster.

Jenkins’ article takes a close look at water usage involved in fracking and makes some interesting points that aren’t often considered.  For example,  the degree to which water is a local issue.  Using four million gallons of water in thirsty south Texas is a much bigger deal that using four million gallons in rainy Pennsylvania.  Also, how much water is actually saved by fracking if the energy harvested is used to replace coal.

Jenkins’ informative article is long and filled with lots of facts and graphics. Here I’m going to produce only his chapter summaries:

Summary: All shale gas wells drilled and completed in the United States in 2011 consumed on the order of 135 billion gallons of water, equivalent to about 0.3 percent of total U.S. freshwater consumption.

Summary: Shale gas consumes about 0.6-1.8 gallons of water per million BTUs of energy produced. If shale gas is used to generate electricity at a combined cycle gas plant and displace coal-fired power, the quantity of water consumed per unit of electricity generated could fall by on the order of 80 percent.

Summary: All shale gas wells drilled and completed in Texas in 2011 amounted to less than 1 percent of all water withdrawals in the state of Texas. That figure could grow roughly three-fold by 2020 as shale production rises, although other developments could reduce the amount of freshwater consumed per well.

Summary: Like politics, water consumption is a local issue. Fracking presents a major source of water consumption in arid locales like Dimmit County, Texas in the Eagle Ford shale region, where fracking represents on the order of one-quarter of the entire county’s water consumption. In contrast, in the more rainy Marcellus shale region of Pennsylvania, Ohio, and New York, the water needs for an entire fracking operation represent about 17 days of average local rainfall in even the driest months of the year.

Throughout the article are revealing water statistics like “…total annual water consumption for fracking in the Barnett Shale, the largest play in Texas, is equal to about 9 percent of the annual water consumption of the city of Dallas.”

What the author does not address is the nature of the “use” of water.  It isn’t quite the same to use water in an urban setting where it is captured in a wastewater system, cleaned,  and recycled as it is to pollute it mightily then inject it into a deep well where it is taken out of nature’s hydrological cycle.

Source: Wall Street Journal

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Copper as a Water Contaminant

Copper is a reddish naturally occurring metal. In water it is typically dissolved as a divalent cation (Cu +2). There is lots of copper in the environment since it is  widely used to make copper pipe and tubing, and copper compounds are used as pesticides and herbicides.

The most common way for copper to get into drinking water is through corrosion from copper plumbing fixtures.

Native copper. As you would expect, it’s copper colored. It’s good to make wire with, but bad for your liver and kidneys if you ingest too much.

This  may cause high levels of copper in drinking water. The presence of copper corrosion is often indicated by blue-green staining of fixtures.

Health Effects of Copper

Copper is a necessary nutrient, but too much copper can cause nausea and vomiting, and long-term exposure can lead to liver damage and kidney problems.

Water Treatment for Copper

Copper can be controlled in whole house (POE) applications and plumbing fixtures protected by cation exchange (a water softener), pH control, and film-creating compounds such as polyphosphates. Water with low pH soaks up copper, and usually raising the the pH of the water cures the problem.

For point of use treatment, reverse osmosis removes copper handily—usually around 97%. Copper can also be removed by distillation and activated carbon adsorption.

Between the Tsunami and the Rats, the Fukushima Nuke Is a Disaster Waiting to Happen

Water News in a Nutshell.

 

In a Nutshell:  Japan’s ill-fated Fukushima nuclear power plant seems to be a disaster waiting to happen. The plant’s problems range from the earthquake damage two years ago to a dangerous power issue caused by a single rat in March 1013. Contaminated water leaking into the environment and perhaps the Pacific is the most serious of its current problems, but the jury-rigged plant could turn into a nightmare at any time.

A rat causing a power outage by short-circuiting a temporary switchboard. Another blackout occurring as workers install anti-rat nets. Holes in the linings of huge underground tanks leaking radioactive water, APA reports quoting Associated Press. Japan‘s crippled Fukushima Dai-ichi nuclear power plant has run into multiple problems recently that highlight its precarious state more than two years after its reactors melted down in the wake of a devastating earthquake and tsunami.A makeshift system of pipes, tanks and power cables meant to carry cooling water into the melted reactors and spent fuel pools inside shattered buildings remains highly vulnerable, Nuclear Regulation Authority chairman Shunichi Tanaka acknowledged Wednesday.In the latest development, three of the plant’s seven underground tanks are leaking. TEPCO reported the first leak early Saturday, hours after the plant’s second power outage. Within days, the damage spread to three tanks, paralyzing the plant’s storage plans for contaminated water.”Fukushima Dai-ichi is still in an extremely unstable condition, there is no mistake about that,” Tanaka said at a weekly meeting of the regulatory body’s leaders. “We cannot rule out the possibility that similar problems might occur again. Whenever a problem occurs, it halts the plant’s operations and delays the primary goal of decommissioning the plant.”

The problems have raised doubts about whether the plant can stay intact through a decommissioning process that could take 40 years, prompting officials to compile risk-reduction measures and revise decommissioning plans. The regulatory watchdog said Wednesday that it was increasing the number of inspectors from eight to nine to better oversee the plant.

Just over the past three weeks, there have been at least eight accidents or problems at the plant, the nuclear watchdog said.

The first was March 18, when a rat sneaked into an outdoor switchboard – which was sitting on a pickup truck – powering the jury-rigged cooling system and several other key parts of the plant, causing a short-circuit and blackout that lasted 30 hours in some areas of the plant. Four storage pools for fuel rods lost cooling during the outage, causing Tokyo Electric Power Co., the plant’s operator, to acknowledge that it had added backup power only to the reactors, despite repeated concerns raised over a pool meltdown.

The cause of the outage wasn’t clear at the time, but TEPCO later released a photo of the electrocuted rat, which had fallen on the bottom of the switchboard outhouse. The most extensive outage since the crisis started after the March 2011 disasters caused some Fukushima residents to even consider evacuation.

Two weeks later, a new water processing machine designed to remove most radioactive elements temporarily stopped after a worker pushed a wrong button. The next day, one of the fuel storage pools lost power again for several hours when part of a wire short-circuited a switchboard while an operator installed anti-rat nets. TEPCO reported three other minor glitches on the same day, including overheating of equipment related to boron injection to the melted reactors.

Regulatory officials acknowledge that rats and snakes are abundant at the plant, and TEPCO has started to take steps to protect pipes and cables from rat gnawing. Replacement of parts and equipment to those of higher quality and long-term use is in progress.

TEPCO says none of the about 120 tons of radioactive water that leaked was believed to have reached the nearby Pacific Ocean. Experts suspect the radioactive water has been leaking since early in the crisis, citing high contamination in fish caught in waters just off the plant.

The contaminated water is by far the most serious of the recent problems because of its potential impact on water management and the environment.

The tanks are crucial to the management of contaminated water used to cool melted fuel rods at the plant’s wrecked reactors. The reactors are stable, but the melted fuel they contain must be kept cool with water, which leaks out of the reactors’ holes and ruptures and flows into basement areas.

“The contaminated water situation is on the verge of collapse,” Tanaka said. But he said there was no choice but to keep adding water, while trying to seek ways to minimize the leaks and their risks.

To address local outrage over the recent problems and TEPCO’s failure to detect problems earlier, company president Naomi Hirose traveled to Fukushima and apologized Wednesday for the problems. He promised to expedite the construction of steel containers and move all the water there from the underground tanks, at the request of Industry Minister Toshimitsu Motegi.

The underground tanks, all built by Maeda Corp., come in different sizes, including one the size of an Olympic-size swimming pool and similar to an industrial waste dump. They are dug into the ground and protected by two layers of polyethylene linings inside the outermost clay-based lining, with a felt padding in between each layer.

Regulators suspect a design problem with the underground tanks, which TEPCO allegedly chose over steel tanks as a cheaper option.

“The nuclear crisis is far from over,” the nationwide Mainichi newspaper said in a recent editorial. “There is a limit to what the patchwork operation can do on a jury-rigged system.”

Source: Global Post. 

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Grazing in the Rain Garden

By Janice Kaspersen, Editor, Stormwater.

Water News in a Nutshell.

In A Nutshell: Rain Gardens are natural water savers that enhance the beauty of homes and serve as natural filters for polluted water.   Is it a good idea to grow edible plants in rain gardens, since they will be watered with polluted urban stormwater? Australian researchers are working on the answer.

Rain gardens are now a common sight in many cities, but finding the right mix of plants to include in a rain garden can be challenging. For the people whose homes or businesses they occupy, the plants’ attractiveness is usually a priority. In some areas, you need to make sure the plants can withstand dry spells; you don’t want to end up irrigating your rain garden.

It’s been suggested that rain gardens be used to grow vegetables, and at first glance this seems to be a good two-birds-with-one-stone solution: growing something useful with a resource we’ve saved from going down the drain. But some have raised an alarm about the dangers of eating what we’ve irrigated with urban stormwater. One purpose of a rain garden or bioswale, after all, is to help filter pollutants from runoff; in high-traffic urban areas, pollutants might become concentrated in the soil, and plants uptake many of them, so do we really want to eat what grows there?

Yes, some Australian researchers say, we do. An ongoing experiment at the University of Melbourne is using roof runoff to irrigate two rain gardens planted with vegetables. Two conventional vegetable gardens—irrigated from the public water supply—are located nearby, and all four are heavily monitored.

In fact, the researchers say, nutrients that commonly enter runoff from landscape fertilization are actually beneficial to the plants. And other pollutants like metals haven’t been a problem so far; according to one researcher, “The filter layers in the rain garden are also doing their work by preventing heavy metals from urban water runoff entering our waterways, while also remaining at safe levels in plants. In contrast we revealed that crops irrigated by tap water actually contained higher levels of copper due to the pipes used.”

Granted, the Melbourne experiment is using roof runoff rather than street runoff as the source of irrigation. But it’s this type of experiment—rather than speculation or guesswork—that we need to see more of.

Rain Garden


Source: Stormwater.

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If there is no water in the dam, should we urinate into it? Ajit Pawar’s crass remark on drought in Maharashtra

A report from India Today.

Water News in a Nutshell.

 

In a Nutshell: There is great tension in the state of Maharashtra about the acute water shortage. When Deputy Chief Minister Ajit Pawar made an apparently insensitive comment about his state’s  water shortage, tempers flared and he was called upon to resign.  

Maharashtra Deputy Chief Minister Ajit Pawar has stirred up a hornet’s nest with his comments – laced with crass humour — ridiculing the acute water scarcity in the state .

Pawar ridiculed a farmer who has been on a fast for over 55 days, demanding the release of water from a dam for his scorched field. In an outrageous statement, Pawar said, “This person from Solapur by the name of some Deshmukh is sitting on a hunger-strike for 55 days demanding water be released from the dam. But if there is no water there what should we release? Should we urinate there? In times without water, even urine is hard to come.”

While Pawar’s supporters broke into hysterical laughter at his “joke”, the comment has been equated with the famous insult by a Russian princess who said, “If they don’t have bread, let them eat cake.” Incidentally, Pawar is the nephew of Union Agriculture Minister Sharad Pawar, who has been promising relief for farmers.

Ajit Pawar’s Comments on Water Shortage Caused Calls for His Resignation

Pawar was addressing a rally in Inapur in Pune when he cracked what was his “joke” on the water crisis in Maharashtra. Perhaps realising his blunder, Pawar immediately said, “I am sure you all are thinking that I am drunk in the day itself.”The NCP has refused to offer any explanation on the issue, but this remark has not gone down too well within the party that is embarrassed to speak on it.A senior NCP leader in the state said, “It is unfortunate that he ended up saying that. It is certainly not even a matter to joke about and this comment will have severe repercussions in the coming days as it has given the opposition enough ammunition to fire at us.”

The BJP called the comment ‘crude’ and said that it reflected the arrogance with which Pawar, who has recently been re-appointed as the Deputy CM, treats the water crisis. “This is the lowest one can stoop down in politics,” a BJP leader said.

Incidentally, activists are up in arms against the state establishment for bringing the state to this point in terms of water management. Activists claim that the draught, which is the worst in Maharashtra since 1972, is a man-made problem, especially created by politicians who have bungled up the irrigation projects.

At the helm of the scam allegedly, is Pawar himself, who was forced to resign as the deputy CM last year after revelations were made by then IAC activist Anjali Damania.

 

Source:  India Today.

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NRDC Wages War on Water Leaks


Posted April 8th, 2013

Environmental Group Says That More Accurate Water Meters Are Essential

Water News in a Nutshell.

 

In a Nutshell: The National Resources Defense Council believes that more accurate water meters will save much water and much money for consumers.  Currently 10 percent of US homes have leaks that waste 90 gallons or more per day, and meter standards go way back into the last century.

 

 

Customer meters are the cash register for a utility. If not all meters are accurate then some customers are subsidizing the consumption of other customers because our rates by necessity need to recover all costs incurred by the system.Anastasia Valdes,  Senior Resource Analyst,  San Antonio Water System.

The Natural Resources Defense Council (NRDC), in a groundbreaking partnership with utilities from across the nation, submitted a proposal to the American Water Works Association (AWWA) to revise national accuracy standards for new water meters to combat the unnecessary waste of water from low-level leaks, according to a March 2013 press release.

The AWWA is the national non-profit organization that publishes standards for mechanical water meters used to measure customer water usage.

NRDC blames much water waste on antiquated water meters.  According to the press release:

Current AWWA standards need to be improved to keep up with today’s water meter technology. The minimum flow rates at which meters are required to be tested have not changed since the first AWWA standard for cold water meters was proposed in 1921. Today, a water meter commonly installed in a new single family home is only certified to be accurate for flows down to 1/4 gallon of water per minute. A continuous flow of 1/4 gallon per minute is equivalent to 360 gallons per day. Lower flows, such as those from a dripping faucet, a running toilet, or a leaky irrigation system, may run for days, weeks or months at levels below 1/4 gallon per minute, and not be fully recorded – or recorded at all – by water meters. Consumers can lose 100 gallons a day or more from unrecorded or under-recorded leakage. This type of water waste contributes to higher bills for all consumers as utilities recover the cost of these water losses through higher and more frequent rate increases.

“Water leaks are incredibly common, often lurking unseen in our homes and businesses and wasting an enormous

Minimum flow accuracy standards for water meters haven’t changed since 1921.

amount of water,” said Tracy Quinn, NRDC water policy analyst. “The costs for leaks not captured by meters are passed on to all customers and result in higher rates and more frequent rate increases. We can fix this by ensuring that utilities are supplied with more accurate water meters that can better detect hidden leaks. Stronger accuracy standards will lead to the widespread installation of more accurate meters, and major water savings will follow when homeowners fix leaks identified. At a time when we cannot afford to let a drop go to waste, these water saving measures matter more than ever.”More than one trillion gallons of water leak from U.S. homes each year and 10 percent of homes have leaks that waste 90 gallons or more per day, often unbeknownst to homeowners, according to the US EPA’s WaterSense Program.

 

Read the entire press release here.

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Softeners Aren’t As Bad For Septic Systems as You Thought

Water News in a Nutshell.

 

In a Nutshell: An extensive (and expensive) WQA-funded research project indicates that well-tuned, efficient modern water softeners seem to be good for home septic systems, but older, less-efficient softeners degrade the performance of  home septic tanks. 

The following is excerpted from a Press Release issued during the Water Quality Association’s annual convention in April, 2013. In the Gazette’s opinion, the reported research is at best another way of saying, “Water softeners aren’t as bad as you thought they are.” 

INDIANAPOLIS, April 2, 2013 /PRNewswire/ — Water softeners set with appropriate salt efficiency do not harm septic systems and may actually help them, according to a new study released today at WQA Aquatech USA.

The Water Quality Research Foundation commissioned Virginia Polytechnic Institute and State University to conduct independent and scientific testing on the issue in 2012.  The result is an official report, “Changes in Septic Tank Effluent Due to Water Softener Use.”  Nearly $100,000 was invested for this 18-month study, which included many site visits and the work of numerous trained experts from WQA, NOWRA, regulators and NSF International.

According to the authors of the study: “The data indicate that the use of efficiently operated water softeners improves septic tank performance, while the use of very inefficient home softeners may have a negative effect on solids discharge to the drain field and the level of impact will depend on the level of hardness in the water, whether the regeneration waste is discharged to the septic tank, and the amount of excess sodium present in regeneration wastes.”

Meter-controlled softeners can be set up very efficiently. Twin metered softeners, like the one pictured above, are the most efficient of all.

Softeners are often the enabling technology that keeps the rest of our houses running effectively by preventing damaging scale build up, said Dave Haataja , executive director of WQA.  In areas with especially hard water, softeners are a necessity for anyone who doesn’t want to constantly buy new appliances and replace pipes and fixtures.  Comprehensive independent studies have also shown many other practical advantages: Saving energy and money, reducing the use of harmful detergents, and keeping our landfills a little less full.

To obtain the most accurate results possible, two different approaches were taken by those conducting the research.  One study in a controlled laboratory setting examined a range of softener/septic reactions.  Then to look at real-world conditions in everyday circumstances, case studies were conducted in the field.  The authors also looked at previous studies and tests.

WQA and NOWRA have collaborated to update the “Guidance for the Use of Water Softening and Onsite Wastewater Treatment Equipment” to include recommendations for use of water softeners with higher salt efficiencies, which this study indicates will minimize potential impacts on septic tank performance.

The Water Quality Association, a non-profit organization that seeks to uphold high standards in the water treatment industry, has committed to education programs to help disseminate sound practices for those with softeners and septics.  The association provides information through its professional training and certification programs and other venues.

The Water Quality Research Foundation (WQRF), formerly The Water Quality Research Council (WQRC), was formed in 1949 to serve as a universally recognized, independent research organization.  WQRF has invested hundreds of thousands of dollars to commission credible third-party testing to offer hard data to consumers, those in the industry and policymakers.

 

 

SOURCE:  Water Quality Association

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Ice-Age Snake Valley Water Will Remain in Utah

Water News in a Nutshell.

 

In a Nutshell:  Utah Governor Gary Herbert won praise of environmental groups and residents of Utah’s Snake Valley by refusing to sign an agreement that would have given half of the ancient aquifer under Snake Valley to thirsty Las Vegas.  But . . . it may not be over yet.
 
After four years of negotiations, Utah Gov. Gary Herbert on Wednesday rejected an agreement with Nevada that would allow Las Vegas to pump massive amounts of groundwater from the states’ shared border.

The water comes from an ice-age aquifer under the 120-mile-long Snake Valley, which supports ranching and farming on both sides of the border.

Nevada has already signed the agreement, which took four years to negotiate and allows the Southern Nevada Water Authority to build a 263-mile pipeline stretching from rural areas on the Utah-Nevada border to Las Vegas.

Snake Valley Wetlands

In a statement announcing his decision, Herbert said he could not sign the agreement because Utah residents in the affected area oppose the deal.

“A majority of local residents do not support the agreement with Nevada,” Herbert said, “Therefore, I cannot in good conscience sign the agreement because I won’t impose a solution on those most impacted that they themselves cannot support.”

Herbert also called the agreement one of the most complex emotional issues he’d dealt with as governor.

Herbert’s lawyers have said that if he did not sign the agreement, Las Vegas will grab a share of the groundwater anyway.

Scott Huntley, spokesman for the Southern Nevada Water Authority, said his agency hadn’t reviewed the decision and didn’t have immediate comment.

“This agreement was negotiated over many years and in good faith,” said Leo Drozdoff, director of the Nevada Department of Conservation and Natural Resources. “We are disappointed by this decision and we are evaluating all of our options in light of Gov. Herbert’s decision.”

Utah water attorneys have said the agreement was a better option for the state than a long court battle with Nevada.

“In the absence of these agreements, Nevada, because of its more pressing need for water, may simply appropriate the remaining available water in the Snake Valley groundwater system to the exclusion of Utah’s needs for future water supplies,” three lawyers advised Herbert in a report filed in November.

During an interview Wednesday afternoon, Herbert said Nevada will have to come back to the table with another agreement before any water is extracted.

If there’s a conflict or the state’s water is taken “inappropriately,” Utah would take the matter to court, Herbert said.

Under the deal, Snake Valley’s groundwater would have been evenly split between Utah and Nevada.

Patricia Mulroy, the general manager for the water authority, has said the deal would reduce Las Vegas’ reliance on the drought-prone Colorado River.

Herbert said last week that pumping groundwater could dry out Snake Valley, which could leave Utah’s heavily populated Wasatch Front vulnerable to dust storms and worse air pollution.

Dozens of environment groups, who have urged Herbert to reject the deal for those and other reasons, praised Herbert’s decision.

“Overall, it’s a good psychological win,” said Susan Lynn, a former coordinator with the Great Basin Water Network, which opposes the pipeline. “We think the governor was very brave and stood with the people of Utah to support their desires and wishes.”

But she also called it “a mixed blessing,” saying her group was bracing for a possible federal lawsuit by the Southern Nevada Water Authority.

Scot Rutledge, executive director of the southern Nevada-based Nevada Conservation League, said his group is concerned with the project’s environmental impacts and the potential “rate shock” consumers would bear if the expensive proposal yields less water than expected.

“We think it’s a boondoggle,” Rutledge said. “Any decision … that slows down this proposal to develop water is good news.”

The agreement called for pumping to be stopped if the water is extracted faster than it can be replaced by surrounding mountains. It would also postpone the pumping for 10 years until a review of environmental conditions is completed.

Herbert is still open to an agreement in the future, which he said would be best for both states in the long run.

“We just haven’t been able to come to an agreement that the people of Utah, particularly those most impacted, feel is in their best interest,” Herbert said. “So we have to live with the consequences, whatever they may be, of not signing the agreement. But we clearly want to leave the door open.”

 

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How Reverse Osmosis Tanks Work and How to Take Care of Them

By Pure Water Annie

Gazette Technical Wizard Pure Water Annie Clears Up the Nagging Questions about Reverse Osmosis Tanks That Have Been Keeping You Awake

Water Flow

  • A reverse osmosis tank is simply a miniature well tank. Pressure tanks on wells and RO tanks work the same way.
  • Water enters and leaves the tank through the same tube.

Does Water Come Into Contact with the Plastic/Metal Shell?

  • Inside the tank is a bladder made of a material called butyl. In metal tanks, the upper water compartment of the tank is lined with a plastic liner so that water does not touch the metal.  It touches only the butyl bladder, the plastic liner, and the tank spout (usually stainless steel or hard plastic) as it enters or leaves the tank.

Air Pressure and Reverse Osmosis Tanks

  • There is a small air charge under the bladder. It’s the air pressure that pushes the water out of the tank when you open the faucet.
  • When you purchase an RO unit or a new tank, the tank is usually pre-charged with air. But tanks are like automobile tires: you have to put air in them as part of normal maintenance.
  • The air valve to check the pressure is located on the side or on the bottom of most RO tanks. It has a cap like an auto tire air cap.
  • The standard air charge for undersink RO tanks is about seven psi when there is no water in the tank. You have to empty the tank of water in order to check the air pressure.
  • To check the pressure accurately, you need a low pressure air gauge. You can find these at auto parts stores or hardware stores.
  • To add air to the tank you need a high tech tool called a bicycle pump. These are also available at hardware stores.

Putting too much air in the tank will not give you more pressure at the faucet; it will just give you less water in the tank.


  • If you want more capacity, it’s usually easier and more economical to use two (or more) standard-sized tanks rather than a large tank. To join two tanks, all you need is a single tee and some tubing. The orange tube in the picture connects the tanks to the RO unit. The tanks don’t need to be the same size or the same style. They will interact perfectly together.

Tank Capacity

  • Some of the tank’s inner capacity is taken up by air and part is taken up by the bladder. Therefore, for practical purposes, the stated volume in gallons of the tank is about twice what the tank will actually hold in terms of usable water. You’ll get about two gallons of usable water from a four gallon tank. This will vary according to your inlet water pressure, the temperature of the water, the condition of the membrane and prefilter of your RO unit, and a few other variables. But don’t expect four gallons of water from a four gallon tank. On the other hand, two gallons is a lot of water unless you’re filling an aquarium or hosting a dinner party for 18.

Metal or Plastic?

  • Metal tanks and plastic tanks yield water of equal quality. Plastic tanks are heavier and cost more than metal tanks, as a rule. The main advantage of plastic tanks is that the do not rust. Normally, metal tanks don’t rust if you keep them dry.

Tank Valves

  • A tank valve is an essential part of the RO unit, although many cheap RO units are built without a tank valve. Without a tank valve, it is necessary to empty the tank to do a minor repair on the RO unit. The valve allows you to isolate the tank from the rest of the RO unit. This is a great advantage when you perform routine maintenance or service on the RO unit.
RO tanks are interchangeable. You don’t have to replace the tank on your RO unit with one of the same brand or same size.