The Pure Water Occasional for January 12, 2015
In this mid-January Occasional, you’ll hear about gelatinous creatures that are heartless, brainless, and immortal, mysterious disappearing water, muddy tapwater on Guam, putrid wastewater in Nigeria, the death of the Mayan civilization, frozen water pipes, disgusting sea lice, and the heartbreak of premature microfiltration membrane failure. Read also about Bill Gates, Taylor King, Hannah Thompson, and Jeff Pleadwell. Hear about ultraviolet water treatment, reverse osmosis tanks, Des Moines’ surprising lawsuit, a new contaminant called chlorpyrifos, and, as always, there is much, much more.
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.)
Jellyfish: Ancient, Gelatinous, Diverse
Jellyfish in a group are called a smack. Don’t make a fool of yourself by calling them a herd.
Some things you may not know about one of earth’s most ancient creatures:
They have been around longer than the oldest of dinosaurs, approximately three times as long. They go back at least 500,000,000 years.
Although they are called fish, they actually aren’t. They are zooplankton.
They are heartless and brainless and made almost entirely (up to 98%) of water. When exposed to air, they can actually evaporate.
Some, but not all, have eyes. One variety has 24 eyes, in fact, and has a full 360-degree view of the world.
One species, Turritopsis nutricula, has the ability to renew its cells and is, therefore, theoretically immortal.
They conveniently eat and defecate through the same orifice which serves as both mouth and anus.
Just to be different, they have a unique group name. A group of fish is called a school, but multiple jellyfish are referred to as a bloom, a swarm, or a smack.
They are deadly and they don’t mind to sting. One species can kill a human in a matter of minutes with a single sting. And jellyfish stings are very painful.
They come in all sizes. They range in size from a few millimeters in diameter to 440 lbs. The longest jellyfish has tentacles that can extend 120 feet.
Some are edible. They are a popular delicacy in places like Japan and Korea, but haven’t caught on in most parts of the world. In Japan they make jellyfish candy.
Jellyfish have been used in space experiments because of their similarity to humans as regards adaptation to zero-gravity environments.
Jellyfish live in every ocean and can be found from the surface to the deep sea.
They are expected to fare well with global warming. In fact, many experts believe that they will overpopulate the world’s oceans.
See also in the Gazette: The Immortal Jellyfish.
Scientists: Great Lakes Teeming With Tiny Plastic Fibers
TRAVERSE CITY, Mich. — Scientists who have reported that the Great Lakes are awash in tiny bits of plastic are raising new alarms about a little-noticed form of the debris turning up in sampling nets: synthetic fibers from garments, cleaning cloths and other consumer products.
They are known as “microfibers” — exceedingly fine filaments made of petroleum-based materials such as polyester and nylon that are woven together into fabrics.
“When we launder our clothes, some of the little microfibers will break off and go down the drain to the wastewater treatment facility and end up in our bodies of water,” Sherri “Sam” Mason, a chemist with the State University of New York at Fredonia, said Friday.
The fibers are so minuscule that people typically don’t realize their favorite pullover fleece can shed thousands of them with every washing, as the journal Environmental Science & Technology reported in 2011.
Over the past couple of years, Mason and colleagues have documented the existence of microplastic litter — some too small to see with the naked eye — in the Great Lakes. Among the particles are abrasive beads used in personal care products such as facial and body washes and toothpastes. Other researchers have made similar finds in the oceans.
A number of companies are replacing microbeads with natural substances such as ground-up fruit pits. Illinois imposed a statewide ban on microbeads last year. Similar measures were proposed in California and New York.
But microfibers have gotten comparatively little attention. They’ve accounted for about 4 percent of the plastic litter that Mason and her students have collected from the Great Lakes. The group drags finely meshed netting along the lake surfaces, harvesting tens of thousands of particles per square mile, and study them with microscopes.
About three-quarters of the bits they’ve found are fragments of larger items such as bottles. Smaller portions consist of microbeads, Styrofoam and other materials.
But when Mason’s team and a group from the Illinois-Indiana Sea Grant program took samples from southern Lake Michigan in 2013, about 12 percent of the debris consisted of microfibers. It’s unclear why the fibers were three times as prevalent in that area as elsewhere in the lakes, although currents and wave actions may be one explanation, said Laura Kammin, pollution prevention specialist with Sea Grant.
Ominously, the fibers seem to be getting stuck inside fish in ways that other microplastics aren’t. Microbeads and fragments that fish eat typically pass through their bodies and are excreted. But fibers are becoming enmeshed in gastrointestinal tracts of some fish Mason and her students have examined. They also found fibers inside a double-crested cormorant, a fish-eating bird.
“The longer the plastic remains inside an organism, the greater the likelihood that it will impact the organism in some way,” Mason said, noting that many plastics are made with toxic chemicals or absorb them from polluted water. She is preparing a paper on how microplastics are affecting Great Lakes food chains, including fish that people eat.
There’s also a chance that fibers are in drinking water piped from the lakes, she said. Scientists reported last fall that two dozen varieties of German beer contained microplastics.
Because microfibers are used so widely, there’s no obvious solution, Mason said. Persuading people to stop wearing synthetic clothes likely would be a tougher sell than the idea of switching facial scrubs.
But pollution prevention remains the best way to protect the lakes, Kammin said.
“It’s very hard to remove these microplastics once they’re out there,” she said.
Source: New York Times.
Top Water News of the Week: January 12, 1015
There were hundreds of water stories this week about water main breaks caused by cold temperatures. It is not air temperature that breaks city water lines; it is the rapid change in water temperature.
There were also numerous stories about people with failed dreams. If you haven’t yet acted on your dream of owning a reverse osmosis unit, here’s the solution.
There is growing evidence that the great Mayan civilization was brought down by drought. Read the Washington Post article.
Water at beaches can be polluted with bacteria from drain water. This article asks if surfing in polluted water can kill you. The moral is don’t surf within three days of a heavy rain.
Bill Gates paused, then sipped from a glass of sewage water that had just been processed through the Janicki Omniprocessor that he sponsored.
Water mystery. What happened to 540,000 gallons of water billed to a vacant D.C. home?
Guam restaurant owner speaks out against local tap water
Guam business owner Jeff Pleadwell holds up two water filters from the water filtration system at his seaside restaurant and bar, Jeff’s Pirates Cove. The left filter is new while the other was used for 30 days on the main line from Guam Waterworks Authority, which supplies water to the restaurant. The filter typically should last about a year, said Pleadwell, but he says he has to change his every month because it becomes clogged with “mud” and causes the water pressure to the building to decrease. Read the full story.
Although Hannah Thompson of Norco scored 10 goals in a recent water polo playoff game, it’s Rancho Cucamonga that’s really on a roll. As football season winds down, it’s time to tune in to America’s real national pastime–water polo.
Tulsa high school student Taylor King is raising money to provide water filters for Ethopian students.
The Algonac water department is experiencing premature failure of costly microfiltration membranes. Find out how long these expensive membranes last, and why you shouldn’t order them from Australia.
St. Mary’s Hospital in Green Bay had to close because of a water main break. Patients were moved to another hospital.
An insecticide used on corn and other U.S. crops poses health risks to workers who mix and apply it and also can contaminate drinking water. The EPA report finds that the pesticide poses risks to workers.
The report is an update, based on new research, to a 2011 assessment of the health impacts of the pesticide chlorpyrifos (pronounced KLOR – pie -ra – phos), which remains one of the most commonly applied organophosphate pesticides. It has been banned for more than a decade for household use but is still used commercially on corn, soybeans, fruit and nut trees and some golf courses.
Ocean warming speeds up cycle of climate change. Since 70% of the planet is covered by clear blue water, anything that reduces the oceans’ capacity to soak up and sequester carbon could only make climate change more certain and more swift.
Sun on the water, as Arctic ice increasingly melts, is part of the “positive feedback” process warming the oceans and reducing CO2 storage.
Moving water south next step in Everglades restoration. There are two big problems facing hydrologists and engineers working to restore flows in the historic Everglades: inadequate water drainage and storage infrastructure and too much phosphorus in Lake Okeechobee.
Canal could turn Lake Nicaragua into ‘dead zone.’ The Interoceanic Canal that will run through Lake Nicaragua could kill life in the vast lake and have other serious effects on the country’s environment and economy unless safeguards are put in place, an independent international panel of experts has warned.
“Impacts on water and sediments are of concern because Lake Nicaragua is one of the paramount tropical lakes in the world, with profound ecological, environmental and economic value.” The works could even create a “dead zone”: an area of the lake with no aquatic life,
Lawsuit likely over nitrates in water. After years of struggling to keep drinking water for almost 500,000 residents in Des Moines, Iowa and its surrounding areas clear of contaminants largely from upstream farms, the Des Moines Water Works board says it plans to sue three counties.
It could be one of the first lawsuits in the U.S. filed by a water utility holding local officials responsible for pollution from farm drainage systems.
Yamuna water not fit even for bathing, says pollution board report. Despite the Supreme Court’s intervention and attempt to clean the Yamuna in Delhi, the level of pollution in the river remains toxic with the water not even fit for bathing.
Nigeria: 90 percent wastewater discharged directly into rivers harmful, says UN report. Over 90 percent of wastewater discharged untreated directly into rivers, lakes and oceans in developing countries is harmful, a UN report has said.
According to the report, the impact of wastewater on the environment and human health is not only striking but frightening and harmful.
Two million tons of sewage, industrial and agricultural waste was discharged into the world’s waterways.
At least 1.8 million children under five-years-old die as a result every year. That is, one child lost every 20 seconds due to water- related diseases.
Inadequate infrastructure and lack of financial resources are largely to blame for the wastewater menaces that plague most developing countries, especially their cities.
In these countries, septic tanks receive the faecal waste of most urban dwellers, while other household liquid wastes are directed into the nearest drains.
Because drainage system costs are frequently prohibitive, majority of urban drains are open, lending themselves to misuse and sometimes serving as defecation points for households without adequate sanitation facilities.
Industrial wastewater from breweries, textile, mining, chemical and pharmaceutical industries is usually discharged into these open drains or into water bodies without any pre-treatment, posing health hazards.
Sea lice are parasitic crustacea that feed on the flesh of farmed salmon until the salmon die or the sea lice are removed.
Sea lice pesticides used in salmon industry may be hazardous. Federal government scientists are raising concerns about the chemicals used to fight sea lice in the New Brunswick salmon farming industry.
Pure Water Gazette technical writer Pure Water Annie explains how to put air into a reverse osmosis tank.
The valve for adding air to this standard reverse osmosis tank is covered by the blue cap under the label. With some older metal tanks, the valve is at the very bottom of the tank under the black tank stand and hard to reach if the tank is filled with water.
If you have an undersink reverse osmosis unit, you’ll eventually have to add air into the storage tank. If you don’t add air, after a time you’ll have to settle for a slow trickle of water coming from the faucet and wait a couple of hours for water to fill your spaghetti pot. Even if your storage tank is full of water, you’re out of water if there’s no air to push it out of the tank.
You can put air into your RO tank at any time, but the best time is when you change your filter cartridges. When the all the cartridges have been replaced, lock open the RO faucet on the sink top and let all the water run out of the storage tank. When water stops coming from the faucet, try picking the tank up. If it’s light—as in empty—it doesn’t need air. But if there is still water in the tank that won’t come out, you need to add air to the tank.
To add air, you’ll need a pump—an ordinary bicycle pump is best—and if possible a low-pressure air gauge—one that is accurate below 10 psi. Most ordinary tire gauges aren’t accurate at low pressure.
Although you can use a small air compressor, the best tool for adding air to an RO tank is a plain old bicycle pump. A low-pressure tire gauge is the only other tool you need.
To add air, locate the air valve on the tank. In most modern tanks, it’s on the side near the bottom, but it can be near the top or hidden on the very bottom of the tank under the tank stand. The air valve is normally capped. When you’ve removed the cap and attached your pump, begin pumping air into the tank. As you pump in air, water will issue from the open faucet. Pump until the tank is empty (no more water will come from the faucet), then check the pressure. Add or let out air as needed to leave about 5 to 10 psi in the empty tank.
If you want more information about adding air to an RO tank, there’s a bigger article with pictures on the Pure Water Gazette’s site.
by Gene Franks
Although ultraviolet light has several water treatment capabilities, such as reducing VOCs, chlorine and chloramine, its main use by far is for microbe control.
Getting rid of microbial water contaminants can be done with chemicals, like chlorine or chloramines, by very tight filtration, as with ceramic filters, or by disabling the microbes with ultraviolet light.
Ultraviolet, UV, is not new. As early as 1877, the germicidal properties of sunlight were known.
Landmark events in the development of modern UV treatment include the use of mercury lamps as an artificial germicidal light source (1901), the development of quartz as a UV transmitting medium (1906), and finally the development of the first genuine drinking water application of ultraviolet as a disinfectant in France in 1910.
The technology is, therefore, a century old, and it is used world wide. Nevertheless, it is still unknown to many US state and local regulating agencies, who continue to view chlorination as the only acceptable way to purify water.
UV treatment works not by “killing” bacteria, protozoa, and viruses, but by altering their DNA so that they cannot reproduce or infect. If chlorination is like chemical warfare directed at microbes, UV is more like a spaying and neutering program.
UV light in the 200 to 300 nanometer (nm) range is the most effective at treating bacteria and viruses. (Visible light falls in the 400-700 nm area.) For most practical UV applications in water treatment today, the light is generated by a mercury vapor lamp, or in a gas mixture that contains mercury. Mercury is the gas of choice because the light it puts out is in the germicidal wavelength range.
Lamp output depends on the concentration of mercury within the lamp, and the concentration depends on pressure. Low pressure lamps (called LP), the most common, produce UV light primarily at 253.7 nm, an ideal treatment wavelength. Some newer lamps are called “low pressure/high output” (LPHO) and some applications now use mixed vapor lamps called “amalgam” lamps. These require more electrical input and generate more UV output. LPHO lamps are roughly twice as powerful as LP, and amalgams may be about four times as powerful as LP.
The Delivery System
The standard way to treat unsafe water with UV is to send it though an elongated chamber where it is exposed to the intense light from the mercury lamp. UV bulbs are long and narrow to allow prolonged exposure as the water passes the length of the lamp.
The lamp itself is inside a transparent tube called the“quartz sleeve,” which protects it from contact with the water, and on the other side of the sleeve there is normally a metal reflective chamber. The water enters one end of the chamber, flows past the lamp to exit at the other end, and is in the process exposed for some time and at close proximity to the UV dosage put out by the lamp.
UV dosage is typically measured in units called “Joules,” and it is most frequently expressed in terms of “mega Joules per square centimeter,” or mJ/cm². (Microwatts per second per square centimeter, expressed as µWs/cm2, and mJ/cm2 represent the same dosage and the two systems are used interchangeably.) The higher the number, the higher the dosage.
The UV dosage received by the water increases as the flow rate of the water decreases, so a UV unit that puts out a dosage of 16 mJ/cm² while treating water at a flow rate of eleven gallons per minute (gpm) will be rated as 40 mJ/cm² if the flow rate is decreased to 4.5 gpm.
Put another way, a UV system rated by its manufacturer to treat water at 40 mJ/cm² at 4.5 gpm will be delivering a dosage of 16 mJ/cm² even if the user exceeds the recommended limit and runs the water at eleven gpm.
The tendency now in UV dosage is to follow the “more is better” view we’ve all been indoctrinated in. If ten nuclear bombs will destroy the world, to be safe we need ten thousand. The most common concerns, e Coli, Giardia, and Cryptosporidium, are effectively eliminated at less than seven mJ/cm². The minimum dosage now recommended by NSF, however, is 40 mJ/cm².
Factors That Affect UV Effectiveness
First, there is the age of the lamp. UV lamps lose strength with time, and almost all manufacturers assume a once-a-year replacement when they design their units. It is a mistake to believe that if the lamp is still burning all is well. UV lamps should be replaced once a year, and when replaced they should still be burning strong.
Then there is flow rate. The unit should be sized to provide adequate protection at the highest possible flow rates, but practicality should tell you that in most residential situations, most water is used at a couple of gallons per minute and a great deal of the time—most of the time, in fact—no water at all is being used.
Also a factor is general absorption of the UV light for unintended purposes. UV makers usually require that the water have less than seven grains per gallon of hardness, less that 0.3 ppm iron, less than 0.05 ppm manganese, and that it be generally clear and free of particulate and tannins. All of these can create situations where the light is absorbed and, therefore, its anti-microbial activity is diminished. Hardness, for example, can form scale on the outside of the quartz sleeve which blocks the passage of light.
A related factor is called shadowing. It is primarily caused by particles in the water which can allow microbes to “hide” from the light and not receive adequate UV dosage. The commonly accepted practice in UV treatment is to put a sediment filter of 5 microns or less in front of the treatment chamber to screen out any particles that could allow shadowing. Even if the water looks perfectly clear to the eye, putting a five-micron filter in front of the UV unit is a good idea.
UV as a Germicidal Treatment. Pros and Cons
The good thing about UV is that in addition to being a very effective treatment for microbes, it is relatively simple and inexpensive to buy and to maintain. It adds no chemicals to the water and leaves no “by-products.” It is very safe, if you follow a couple of simple rules (like don’t stare at a burning UV lamp because it can damage your eyes, and remember that treatment chambers can be hot to the touch). Compared to ozone, chlorine, or even hydrogen peroxide, UV is a very safe home treatment. Also compared with other treatments, UV requires little maintenance.
The main disadvantage of UV as germicidal treatment is that it has no residual effect. Bacteria are treated when they pass the lamp, but contamination that occurs downstream of the lamp is not treated. Chlorine and chloramine, by contrast, stay in the water from the point of treatment to the final point of use, preventing reinfection. The need for a constant supply of electricity can be seen as an additional disadvantage. If the power goes out, you shouldn’t use the water. Modern UV units often included devices to warn of power failure or even to shut off the flow of water if the power goes off.
UV from Pure Water Products
Classic Plastic Pura Units. We’ve been in business almost 30 years, and Pura was one of our first products. We started selling plastic-housing Pura UV systems just a couple of years after Pura went into business in the late 1980s, so it’s a product dear to our hearts. The Pura #20 lamp, used on all whole house plastic units, is, in fact, our most successful product in terms of sales. We stock all units and all parts, “every nut and bolt,” of plastic housing Pura units. We have an entire website, http://www.purauv.com, devoted to plastic-housing Pura units. We’re the best source, anywhere, for plastic Pura units and parts. We have some expertise with the units and can help with service issues.
Stainless Steel Units. We have stainless units both by Sterilight and Trojan. We stock parts for both Watts and the now-discontinued Pura stainless steel units. Sterilight stainless units are now on our main website. We are factory-direct distributors for Sterilight and Trojan and can supply any replacement parts you need.
This article first appeared in the Pure Water Occasional for May 2011. The current version is updated and revised.
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!”
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