The Pure Water Occasional for February 2, 2015

In this exciting Groundhog Day Occasional, you'll hear about boil water alerts, emergency water filters, Potters for Peace, rivers in the air, and volcanoes stirred up by climate change. You'll learn about the water preferences of groundhogs, drowning without getting in the water,  the tribulations of Mount Polley, the revival of the great iceberg towing scheme, the sewage effects of the Super Bowl, and the anti- water bill protests still raging in Ireland. Finally, you'll hear a lot about water filter carbon, Pure Water Annie will answer your burning questions about air gap faucets, and, as always, there is much, much more.

The Pure Water Occasional is a project of Pure Water Products and the Pure Water Gazette.

To read this issue on the Pure Water Gazette's website,  please go here.  (Recommended! When you read online you get the added advantage of the Gazette's sidebar feed of the very latest world water news.)


You'll sing better.

The Pure Water Occasional Wishes You and Yours the Happiest of Groundhog Days.  We believe that Groundhog Day is a superb holiday because you are not expected to buy anyone anything, send anyone any kind of card, wish anyone merry or happy anything,  or drive anywhere to visit anyone.  It's a good day to stay home and drink water.

Groundhogs and Water

In Spite of Common Misconceptions, Groundhogs Can Swim and Drink Water

It is commonly believed that groundhogs do not drink water. The Wikipedia, for example, states flatly: “ Groundhogs hydrate through eating leafy plants rather than drinking from a water source.” A video, however, refutes this belief, showing one groundhog lapping up some water that was spilled on a board and another who seems to be drinking from a birdbath.  If there's a u tube video, do you need more proof?

Groundhogs aren't often seen in water, but they are good swimmers, as shown in the picture below.

Groundhog Swimming

Will Your Water Filter Protect You if  You Have a Boil Water Alert? 

Adapted from an email communication by Marianne Metzger of National Testing Laboratories.

With the cold weather comes the increased possibility of water mains and pipes bursting.  Pipes and mains are at risk in colder weather due to the expansion and contraction of the pipe material.  Even a 10° change in temperature of air or water can cause significant stress on the pipes. Other factors like the material the pipe is made of, corrosion, soil conditions age. and ground movement also contribute to breaks.

There are approximately 250,000 water main breaks every year in the United States. That's 685 breaks per day.

Water customers in the area of the break may experience a shut off of water while repairs are being made. Additionally, if customers do have access to water, they may be under a boil advisory.

For those with water treatment equipment this can be confusing. Many people assume that their water treatment device will take care of the problem and they can simply ignore the boil water alert. If an ultraviolet light is part of the equipment, they are right. However, homeowners with other types of treatment equipment cannot simply ignore the alert and they may even may be faced with additional maintenance. It is good practice to change out any carbon-based cartridge filter after a boil advisory because carbon can provide the optimum environmental for any bacteria that may be present as a result of the break. This applies to undersink filters and reverse osmosis units. Whole house carbon filters are also at risk of becoming growing beds for bacteria. For water softeners, it is a good rule of thumb to disinfect the system according to the manufacturer’s instructions after any boil advisory to ensure bacteria are not present.

If  you have doubts about the state of your water filter after a boil water advisory, a simple test for bacteria is a good idea. Bacteria tests can be arrange through most city water departments and through independent agencies that do water testing.

Providing clean water to the developing world

Household water treatment offers the best hope for nearly 900 million people.

by Michael D. Robeson

Many Americans take clean drinking water for granted. However, much of the developing world is still grappling with the challenges of supplying water that is safe for human consumption. The problem affects nearly 900 million people around the globe and leads to 2.2 million deaths by waterborne diseases annually. More than half of the victims are under the age of six.

While the danger in urban areas stems from aging or inadequate water treatment infrastructure, the risk is most acute in rural communities lacking the density or the resources to build and support water treatment facilities.

Many rural residents still fetch water from rivers, lakes, ponds and streams contaminated with human and animal waste, whether from open defecation or factors such as seepage from septic tanks and pit latrines. Even people with access to cleaner water from common wells, collected rainwater or centralized taps face the risk of pollution by an unsanitary container or improper storage in the home.

For these reasons, groups such as UNICEF and the World Health Organization (WHO) have long recognized that the most practical immediate strategy for improving rural drinking water quality is to provide solutions for treating and safely storing water at the household level.

The upshot has been the development of a variety of household water treatment and safe storage (HWTS) technologies designed to improve water quality at the point-of-use (POU), as well as the publication of WHO specifications for evaluating the microbiological performance of different HWTS systems in 2011. That 2011 WHO document was the first to establish target performance levels for bacteria, virus and protozoa in POU water treatment, providing a benchmark for measuring the relative effectiveness of each technology option.

From chlorination to filtration

One common POU solution involves chlorination — essentially the same treatment used to disinfect public water supplies in the early 1900s. The most widely adopted model in this scenario was developed by the Centers for Disease Control and Prevention (CDC) and the Pan American Health Organization in response to a 1990s cholera epidemic in South America. Under this model, diluted sodium hypochlorite is manufactured locally, bottled and added to water by the capful for disinfection. Users agitate the water and wait 30 minutes before drinking.

Benefits of this approach include low cost per treatment and proven reduction of most bacteria and viruses. Drawbacks include relatively low protection against parasites such as Cryptosporidium, potentially objectionable taste and odor, lower effectiveness in turbid waters and the need for a reliable supply chain as well as the financial resources to continually replenish the chlorine-bleach solution.

An alternative household water treatment is solar disinfection. Initiated by the Swiss Federal Institute for Environmental Science and Technology in 1991, this strategy requires users to fill plastic soda bottles with low-turbidity water, shake them for oxygenation and place them on a roof or rack for six hours in sunny weather or two days in cloudy conditions. Ultraviolet (UV) light from the sun works in conjunction with increased temperature to improve water quality.

The pros include ease of use, virtually no cost and effective pathogen reduction. The cons include the need to pretreat even slightly turbid water, long treatment times, especially in cloudy weather, the need for a large supply of clean bottles and the limited volume of water that can be treated at one time.

Most other POU options involve some form of filtration designed to remove pathogens by passing water through porous stones and a variety of other natural materials.

Multiple filter varieties

Clay-based ceramic filters, for example, remove bacteria through micropores in the clay and other materials such as sawdust or wheat flour that are added to improve porosity. The best-known design in this category is a flowerpot-shaped device by the nonprofit organization Potters for Peace that holds eight to 10 liters of water and sits inside a 20- to 30-liter plastic or ceramic receptacle, which stores the filtered water. Some ceramic filters are also coated with colloidal silver to ensure complete bacteria removal and prevent growth of the bacteria within the filter itself.

Slow sand filters, on the other hand, remove pathogens and suspended solids through layers of sand and gravel. One common household biosand filter consists of a concrete container incorporating layers of large gravel, small gravel and clean medium-grade sand. Prior to use, users fill the filter with water every day for two to three weeks until a bioactive layer resembling dirt grows on the surface of the sand. Microorganisms in the bioactive layer consume disease-causing viruses, bacteria and parasites, while the sand traps organic matter and particles.

As with chlorination and solar disinfection, both varieties have virtues as well as limitations. Ceramic filters are effective against bacteria and protozoa but not as effective against viruses, are breakable, typically last only two years, require as often as weekly cleaning and have a flow rate of only one to three liters of water per hour. Slow sand filters have a flow rate of 30 liters of water per hour — enough to suit a family’s needs — but again, lack adequate virus reduction abilities, are costly and difficult to transport at 170 lbs. and require periodic agitation and regrowth of the biolayer that can reduce filter efficiency if done improperly.

Both ceramic and slow sand filters also lack residual protection for filtered water, such as that provided by chlorine, raising the risk of recontamination unless a disinfectant is added after treatment.

A third option is a hybrid of the ceramic and sand designs. This approach utilizes porous ceramic particles blended with silver, zinc and copper, and deploys them in a layered configuration similar to slow sand filtration solutions. The filter is delivered in a barrel-shaped device with a strainer that filters out large debris, a ceramic/metal layer that neutralizes harmful microorganisms through an ion exchange process made possible by the unique properties of the clay itself and a built-in storage chamber for up to 18 liters of clean water.

Advantages consist of validated effectiveness in bacteria, protozoa and virus disinfection including industry-first compliance with WHO’s new household water treatment specifications, ion-based residual disinfection that keeps filtered water safe, minimal maintenance and a 10-year lifespan with no added costs for post-filtering chemical treatment or filtration media replacement, keeping costs low over the life of the filter. Downsides include a higher initial cost compared to other products and difficulty in outsourcing fabrication to developing world factories because the unique filtration materials are not locally available.


Implementation challenges

While household water treatment technologies for developing countries are not new, adoption still falls woefully short of need. According to the CDC, over two million people in 28 developing countries now use solar disinfection for daily drinking water treatment; however, that pales in comparison to the 900 million people who lack access to safe drinking water. Likewise, Potters for Peace has distributed over 200,000 ceramic filters in Cambodia and many more in other countries, but this only scratches the surface of a public health problem killing the equivalent of the entire population of Houston every year.

One stumbling block is the need to work through disparate non-retail channels to reach communities in need. Partnerships must be created with different nongovernmental agencies (NGOs) and multiple local organizations in each country. Finding willing partners is difficult, as is developing sustainable financial models for projects requiring donor funding and subsidies.

Therefore, distribution strategies vary widely. In the case of chlorination, implementations range from a faith-based group in northern Haiti making and bottling its own hypochlorite solution to a large-scale program in which NGO Population Services International both promotes and distributes its own product on a country-by-country basis through local channels such as community health workers and private pharmacies. In the case of ceramic filters, Potters for Peace helps local communities set up filter-making factories that in turn sell their products to NGOs. Each solution and supplier must forge its own path.

Equally challenging is the need to select the most appropriate treatment method for a community’s specific circumstances. Variables such as existing water and sanitation conditions, water quality, cultural acceptability, implementation feasibility and availability of a supply chain for refills or replacement parts will affect the decision. In addition, any implementation must include an education component to teach the use of each technology as well as proper sanitation, food and water handling.

Nevertheless, household water treatment holds the potential to save millions of lives. Until universal access to piped treated water is available, if ever, these decentralized technologies and the small-scale humanitarian models required to deploy them are the best hope for reducing the disease and death toll related to dirty water. Creative solutions, entrepreneurship and new business models will be needed to remove distribution obstacles, provide government funding or microfinancing and bring relief to millions of people who put their lives in danger simply by taking a drink.

Source: Water Technology.

Pure Water Gazette Fair Use Statement

Water News for the Week of February 2, 2015

Sky me a river: Scientists say flood threat linked to atmospheric rivers. Atmospheric rivers, as they are called, carry enormous amounts of waters that have caused damaging floods, but predicting where they will strike can help officials avoid harm and possibly manipulate the water for more beneficial usage.

Climate change is lifting Iceland – and it could mean more volcanic eruptions. Iceland is rising because of climate change, with land freed by the melting of the ice caps rebounding from the Earth at a rate of up to 1.4in per year. Researchers believe the extra uplift could be behind an increase in volcanic activity, with three Icelandic eruptions in the last five years shutting down flights and spewing ash in the air.

Could drilling in the Atlantic harm fish, whales, turtles? The swath of Atlantic Ocean the Obama administration may open to oil and gas exploration is an ecologically diverse network of soft-bottom shelves and rocky canyons that includes some of most dynamic and mysterious marine systems on Earth.

If you think our temperatures are going up fast, take a look at what's happening to the oceans.  Excellent article with temperature chart from the Guardian.

Florida looks to recycling, desalination as it faces increasing water supply crunch. Florida is bumping up against its limits on groundwater supply, the primary water resource for the state, officials from water management districts and water utilities have said.


Although it's winter, Lodi Flames fans have a lot to be excited about as players and former players are being chosen for Olympic and All American honors.

 Read the full story in the Lodi News-Sentinel.  For more water polo news, read Total Water Polo.

Towing in icebergs is only one of the ideas that have been advanced for quenching the thirst of dry cities. Read this Living on Earth report.

Brave Virginians jumped into the 37 degree water of the James River in the first annual Shiver in the River event.

Jackson, MS has had numerous boil water alerts lately. Watch this local news report, which may or may not give you confidence that city officials have the safety issue under control.

Mount Polley tailings dam report to be released today. The release of millions of cubic meters of water and potentially-toxic metals was among the largest in the world during the past 50 years. It has sparked widespread concerns about long-term effects on the Quesnel Lake watershed and has put intense scrutiny on tailings dam safety in B.C.

 “Sewage is really an unexploited source of rich information about human activities.”

In 2011, the New York Post illustrated the real-time impact of the Super Bowl Flush by measuring how much water was drawn from local reservoirs to fill up empty toilet tanks. The pattern was clear: a dramatic usage dropoff (7 percent) at kickoff and into the first quarter, and a huge demand for water at halftime (a jump of 4.5% from the previous week at the same time) and immediately after the game (13 percent). In fact, so many people flushed after the game that year (when the Giants defeated the Patriots) that Hillview Reservoir in Yonkers, a 30-feet-deep, 164-acre body of water which supplies New York City’s drinking water, dropped a full two inches.

Read “The Super Bowl of Toilets” in The Daily Beast.

 The anti-water charge protests continue in full force in Ireland.

Who Owns our Water?

North Carolina is fighting a bruising legal battle against Alcoa over the aluminum giant’s claim to a strip of the Yadkin River that it has long used to generate electricity.

At the center of the dispute are a patchwork of federal and state laws that created a quid pro quo between the two: Alcoa could operate dams to make the electricity as long as whatever they did was “in the public interest.”

The public interest in this case was Alcoa’s aluminum manufacturing operations in rural Stanly County that employed thousands over the decades.

That smelter is now gone. But Alcoa still wants the right to dam the Yadkin’s water for its electricity trading operations. The battle, in other words, stems from North Carolina’s refusal to accept that what the law defines as “in the public interest” has changed. In Stanly County, Alcoa was once a factory that turned rural farmland into a middle-class city. Now, it’s another company that sent its jobs overseas.

Alcoa abandoned Stanly County. But it still wants to use the region’s biggest resource: its water.  Read "Who Owns our Water?

Drowning Out of Water

We often think of summer as the season for drowning, but drowning can happen anytime of the year. In fact, every day about 10 people unintentionally drown. One in five that die are under age 14. And you don’t have to be in a pool or body of water to drown. Secondary drowning, also called “delayed” drowning, can happen up to 24 hours after you or your child has left the water. Full report from News4Jax.

Dams are on the decline.

In 2014, 72 dams in 19 states were torn down. That's a record.

That is roughly double the annual number from 10 years ago. Some 1,185 dams have been removed since 1912, according to the group. The fleet of U.S. dams, however, is still enormous. The Army Corps of Engineers counts at least 87,000 dams in its database.  Full story.

Filter Carbon

Carbon, sometimes called "charcoal," is the most universally applied of all water treatment filter media. Residential filters, from the common end-of-faucet taste enhancers to elaborate whole house systems, almost always are carbon filters or use filter carbon as one of their principal ingredients.

Filter carbon is a manufactured product, made commonly from coal, woods, and nut shells.  Not all filter carbon is the same.  It varies depending on the raw material and manufacturing techniques applied. Performance depends on the pore size of the carbon as well as the format produced by manufacturing.  It can be used in granular form (similar to coffee grounds), powder, or tight, molded blocks. It can even be stuck to the surface of other filtering devices like pleated filters or combined in beds with other media like KDF.

Carbon made with bituminous coal is the most common and most universally used.  It has average pour size, containing large and small pores, and is therefore useful in most filtering applications.  Carbon will smaller pores--coconut shell carbon is the most popular--is best at dealing with contaminants like VOCs that require lots of small pores. Large pour carbon, typically made from wood or lignite coal--is best at removing colors from water.

Carbon reduces contaminants either by catalytic action, physical straining, or adsorption.  For example, it acts as a catalyst to convert chlorine to harmless chloride or to break down chloramine.  Although all carbon can perform this function, specially prepared carbon called "catalytic carbon" can do it much faster. Catalytic carbon can also be used to reduce hydrogen sulfide odors or to remove iron from well water.  Most chemical reduction is done by adsorption with the contaminant becoming trapped on the craggy surface of the carbon.  Although this isn't it's best use, carbon can also be used to physically trap particles in granular beds or in carbon block form screen out things as small as bacteria or cysts.

Pure Water Products stocks standard and coconut shell carbon as well as macropore carbon (Jacobi Cororsorb) for color removal.  We stock catalytic carbon in both standard bituminous (Centaur) and coconut shell (Jacobi Aquasorb) varieties. We have many specialty carbon cartridges for all four standard size filters, including catalytic for chloramine reduction,  carbon blocks for lead and cyst reduction, coconut carbon blocks for VOC treatment, and many more. Coming soon: Colorsorb carbon cartridges for tannins.

Pure Water Annie's FAQ Series.

Pure Water Gazette Technical Wizard Pure Water Annie Answers All the Persistent Questions about Water Treatment.

This week's topic: Air Gap Faucets.

I'm buying a new undersink water filter.  Should I get an air gap faucet with it or a standard faucet?

Standard.  Air gap faucets are used only with reverse osmosis units.

Why don't they use them with filters?

Filters don't have a drain line.  The air gap faucet is mainly about the drain.  The "air gap" for the drain is put in the faucet only because that's a convenient place to locate it. The purpose of the air gap is to prevent backflow from the drain to the RO unit.

Why does the air gap faucet need three tubes instead of one?

See the illustration below.  The tube on the left, the one that enters the threaded stem,  carries the drinking water to the spout.  The other two tubes carry the RO unit's reject water to drain.  The small tube carries the it from the RO unit up to the body of the faucet and the larger tube carries it down the to the drain saddle on the home's drain pipe.  The "air gap" occurs between the two tubes.  The two drain tubes are not connected inside the faucet base.  There's an "air gap" between them that prevents backflow.

What's the purpose of the hole in the faucet body under the handle?

The hole, indicated by the arrow in the picture above,  is a drain hole.  If the home's drain is stopped up so that water can't exit via the large drain tube on the faucet, the drain water simply backs up and dumps out of the faucet and (usually) onto the sink top.

How do I fix the problem if water drains onto my sink top?

You have to unstop the undersink drain pipe.  Sometimes it's only a small obstruction in the large faucet drain tube itself.  In that case, you can usually fix the problem by removing the 3/8" (larger) tube from the drain saddle and clearing it.  Blowing through the large tube often clears it.

Is the gurgling sound I hear when the RO unit runs caused by the air gap faucet?

Usually, yes, but any RO drain can be noisy.  Another cause of noisy drains is an improperly placed drain saddle.

Can I replace the air gap faucet with a standard faucet?

Yes, but  you'll have to re-route your drain water.  You don't really have to replace the faucet itself. Simply re-routing the the drain water will get rid of noise and drain water on the countertop.  There's an easy way to use a simple adapter to replace the air gap feature of the faucet with a check valve (one way valve) that will keep water from backing up into the RO unit from a stopped up drain pipe.  The check valve may or may not satisfy your local plumbing code.

The red tube carries drain water from the RO unit up to the air gap.  The black tube carries the drain water back down to the drain pipe. (Click picture for a larger view.)

What size hole do I need to install an air gap faucet?

Standard faucets need only a 7/16" hole in the countertop, but the air gap needs at least a 3/4" hole because of the extra tubes and the spacer (the white object in the picture).

More about air gap faucets, including installation instructions.   



 Please visit our RO Parts Page for tanks and accessories.  We also have dedicated parts pages for countertop water filters, undersink filters, and aeration equipment.  We stock parts for everything we sell.

Thank you for reading.  Please come back next week.

Places to Visit on Our Websites in the meantime.

Garden Hose Filters.  Don’t be the last on your block to own one.

Model 77: “The World’s Greatest $77 Water Filter”

Sprite Shower Filters: You’ll Sing Better!”

An Alphabetical Index to Water Treatment Products

Our famous whole house Chloramine Catcher

Pure Water Occasional Archive: Sept. 2009-April 2013.

Pure Water Occasional Archive: April 2013 to present.

Write to the Gazette or the Occasional:

Fair Use Statement

Please Visit

The Pure Water Gazette – now now with an up-to-the-minute feed of the latest water news.

The Pure Water Occasional

Pure Water Products