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  • Going Off-grid with Water

    With the ongoing droughts, water shortages and rising cost of water supplies, many homeowners are considering rainwater harvesting and storage to tide them over the dry spells, or in some cases, even going off-grid with water completely, in order to lead a self-sufficient lifestyle.

    Regardless of whether you are hoping to cut down on your water bill, be completely self-sufficient, or simply conserve water due to environmental issues, going off-grid with water while living in an urban area is completely feasible — even in areas that do not receive lots of rain.

    Water Sources

    But before you can cut ties with your water utility, you will have to find a water source to tap into. If you have a dam or a stream on your property, you can use this as your water supply, or you can drill a well to tap into groundwater. For properties that don't have access to water onsite, rainwater harvesting is the only option, and for most urban residential areas this is the most feasible water source. An additional benefit of using harvested rainwater for drinking purposes compared to other sources of water is that rainwater is pure and contains no contaminants or pathogens that can be harmful to our health. By comparison, groundwater and surface water often contains a wide range of pollutants that need to be removed before the water can be used for drinking purposes.

    Rainwater Collection and Storage Options

    Any structure with a roof surface can be used to collect, harvest and channel rainwater to a storage tank so that it can be used as needed. The stored rainwater can be used for a wide range of household uses, including domestic use, irrigating plants, washing your vehicle, topping up the pool, or providing drinking water for livestock, pets and even human residents.

    A rainwater harvesting system consists of the following components:

    • Catchment surface — typically a roof, but decks and other surfaces can also be used as a catchment
    • Diversion system — this channels the collected rainwater to your storage system
    • Storage system — rainwater barrel/s or cistern/s that store the collected water for you to use when you need it in the future
    • Distribution system — water pipe network that distributes the stored water to your home, garden, swimming pool, etc
    • Treatment system — the system you use to filter or treat the water to render it suitable for the purpose you intent to use it for



    When choosing rainwater barrels or cisterns for your storage system you must ensure that they are safe. Rainwater tanks must seal securely to prevent pets or children from falling into them. They should also be constructed from food-grade material so that harmful chemicals do not leach into the water stored within them, particularly if this water is going to be used for drinking purposes.

    Rainwater Tanks

    Above-ground rainwater tanks offer a popular water storage solution for urban residential areas as they are available in a variety of different sizes, shapes and colors to enable the homeowner to find an aesthetically pleasing solution that will fit into any space on their property.


    Cisterns are another option for storing a large volume of water either above or below the ground. Cisterns designed for use below the ground are usually quite bulky, but they are able to store large volumes of water without taking up space in your garden that can be used for other purposes. Cisterns designed for use above the ground tend to be smaller, and consequently lighter. This makes them more portable as they are easy to move around.

    Water Treatment

    If you plan on using the harvested rainwater for drinking, it is advisable to treat it beforehand to ensure any potential contaminants are removed. While the risk of contamination is much less than that of other water sources, bacteria, as well as sediment, debris and other particulate matter together any chemicals on the roof surface, can flow into your storage barrels and contaminate your water.  To prevent this, it is essential that you have a pre-storage treatment mechanism installed to remove some of these pollutants before the water flows into the storage tank, followed by an after-storage filtration system such as a Berkey water filter that will remove any contaminants that may be present and render your water safe to drink.

  • Blended Wastewater, An Alternative and Affordable Source for Drought Stricken California?

    Researchers from the University of California, Riverside, have developed an economic model which shows how using a combination of different wastewater treatment processes may provide an affordable source of irrigation water that benefits crops.

    Recycling wastewater for use in crop irrigation is increasingly considered an important solution to addressing California's water crisis during periods of extended drought. However, this comes with its own set of challenges, as the treatment processes required in order for the water to comply with state regulated health standards and to reduce levels of crop damaging salt is costly.

    Courtesy: https://www.flickr.com/photos/agrilifetoday/5012314598 Courtesy: https://www.flickr.com/photos/agrilifetoday/5012314598

    An economic model developed by researchers from UC Riverside demonstrates how blending wastewater that has been treated with different treatment processes can be used to produce an affordable supply of irrigation water that meets, if not surpasses, a wide range of water quality standards. The researchers outline the framework in a paper that was recently published in the American Chemical Society's journal Environmental Science & Technology.

    "While the reuse of treated wastewater is not a new concept, concerns over the rising demand for water from population growth, coupled with both economic and environmental challenges, have made this option more attractive," explain the authors.

    The wastewater reuse model developed by the researchers assumes that the treated wastewater meets state regulated health standards for pathogen removal and aims to produce irrigation water that has a chemical composition specifically tailored to the crops and/or grasses that it will be used to irrigate. According to the researchers, blending wastewater that has been treated by different treatment processes is likely to produce irrigation water that contains nutrients that will benefit specific crops. This would reduce the need for fertilizers and the associated costs, which would then make recycling wastewater more affordable and viable.
    Raw untreated wastewater is usually high in nutrients, including nutrients such as nitrogen, potassium and phosphorus, which are important for plant growth.

    "However, to meet state and federal water quality regulations, most conventional wastewater treatment plants subject this raw effluent to primary, secondary, tertiary, and disinfection processes, which results in significant removal of nutrients," the team explained.

    The research team identified seven different technologies and eleven treatment trains — a sequence of wastewater treatments used in combination to meet a specific health standard — currently used to treat wastewater.

    The researchers tested the economic model on citrus trees and turf grass, estimating and comparing the costs and water quality chemistry of wastewater treated using various treatment combinations. Treatment combinations that were not able to produce irrigation water with an optimal blend of chemistry tailored for crop irrigation were considered unfeasible and eliminated. Other treatment combinations did produce blends that were chemically feasible, however, some were simply not cost-effective for smaller wastewater treatment facilities.

    This economic model shows how wastewater treatment trains can be used to deliver irrigation water optimized for use on a wide variety of crops that have varying degrees of salinity tolerance with much less of a negative impact on soil quality and crops than using recycled wastewater that is treated by conventional processes. Furthermore, pathogens, heavy metals and salinity were reduced to meet existing health standards and safe agricultural practices.

    According to the authors, this blending technique offers an alternative source of irrigation water for agriculture, which if utilized could take the pressure off freshwater resources that would be reserved and available as a coping mechanism during periods of drought-induced extreme water scarcity.

    Journal Reference

    Quynh K. Tran, Kurt Schwabe, and David Jassby. Wastewater Reuse for Agriculture: Development of a Regional Water Reuse Decision-Support Model (RWRM) for Cost-Effective Irrigation Sources. Environmental Science & Technology, (2016).

  • Brain-eating Amoeba, Naegleria Fowleri, a Deadly Emerging Water Contaminant

    A brain eating amoeba is responsible for a deadly emerging disease, that usually always claims the life of the victims it infects. The disease is caused by a parasite known as Naegleria fowleri, or more commonly as the 'brain-eating amoeba'.

    Although still relatively uncommon, the brain disease, known as primary amoebic meningoencephalitis (PAM), is typically fatal and is making news headlines the world over. The outbreaks of this deadly disease have resulted in cautionary warnings not to play or swim in waters that could potentially be infected, and to take precautions not to snort, sniff or squirt water up through the nasal passages, which is the parasite's primary passage of access to the brain.


    While N. fowleri is relatively common in warm water environments, it doesn't appear to cause any harm when ingested. However, a study that was recently published in the Journal - American Water Works Association suggests that N. fowleri is an emerging drinking water pathogen in the US, as drinking water supplies are also used for bathing, showering, topping up swimming pools, etc. The study outlines methods that water utilities can be used to treat drinking water supplies in order to control this emerging contaminant.

    This emerging pathogen is included on the EPA's Contaminant Candidate List (CCL 3) — but what are utilities doing to deal with it?

    According to the Journal AWWA paper: "Few laboratories in the United States or worldwide are experienced with this organism." The methods most commonly used to detect the parasite, which were primarily developed in Australia, include sampling using membrane filtration or centrifugation, with samples then being analyzed in a laboratory. Samples can either be taken from the surface of freshwater bodies, or by collecting samples of biofilm scraped off water pipes or plumbing fittings and fixtures.

    Alarmingly, samples have shown that the brain-eating amoeba can occur in water heaters, sink drains and shower-heads — where it thrives in temperatures of between 25-42 degrees celsius. It can also survive cold winter temperatures and regrow when temperatures warm up again.Yet, while chemical disinfection can effectively remove and control N. Fowleri, utilities have very little control when it comes to maintaining water quality at the end of the distribution network — at the point where it enters a consumer's home.

    According to the Center for Disease Control a person cannot become infected by drinking contaminated water, only when water contaminated with the parasite goes up your nose. Consumers can take the following precautions to avoid becoming infected with the deadly parasite.

    1.  Do not let water enter through your nose when swimming in warm freshwater bodies or in small plastic or blow-up swimming pools. Wear a nose clip or keep your head above water.
    2.  Do not plunge into small pools or bathtubs or let you head go under the water. Rather lower yourself into the water, keeping your head above water.
    3.  Ensure that children are supervised when playing with garden sprinklers or hose pipes, as water can accidentally be squirted up their noses.
    4.  Take care not to let water go up your nose when taking a bath or shower, or when you wash your face.
    5.  Keep your head above water when swimming or bathing in hot springs or other thermal waters that are untreated.
    6.  Avoid water-sports or other water activities in freshwater bodies when water temperatures are exceptionally warm.
    7.  Avoid stirring up bottom sediments when partaking in water-related activities in warm, shallow freshwater bodies.

    Journal Reference

    Bartrand, Timothy A.; Causey, Jonathan Jake; Clancy, Jennifer L. Naegleria fowleri: An emerging drinking water pathogen. Journal - American Water Works Association. (October 2014). 106:10, E418-E432. DOI: http://dx.doi.org/10.5942/jawwa.2014.106.0140

  • Getting the Balance Right: Managing Watershed Quality to Prevent Coastal Dead Zones

    Nitrate-rich agricultural runoff is considered one of the key factors contributing to harmful algal blooms in coastal zones. The Gulf of Mexico is particularly vulnerable to harmful algal blooms for two reasons:

    1) It is a large bay with slow water turnover rates, exacerbated by strong onshore winds; and

    2) Many of the watersheds feeding into it flow through agricultural lands.

    Now a new study, which was recently published in the scientific journal Ecology Letters, examines the link between agricultural runoff and harmful algal blooms in the Gulf of Mexico, The study looks at how the silica:inorganic-nitrogen ratio in the water of 130 lakes that feed into the Gulf of Mexico influence nutrient levels in these coastal waters.

    4558031458_3f8eb334e6_z Satellite Image of Gulf of Mexico Algae Blooms

    The study is important, especially considering that during 2016 the Gulf experienced an above average sized dead zone as a result of a combination of agriculture, algae and weather patterns. Long-term records of water chemistry in the Gulf of Mexico show that the silica:inorganic-nitrogen ratio has changed dramatically over the last century, shifting more towards nitrogen. There are two potential explanations for this shift: 1) silica may be removed by reservoirs and dams dotted along the watershed; and 2) the input of nitrogen (from nitrate-rich fertilizers) from agricultural runoff is so high that it forces the ratio of silica:nitrogen downward. This new study shows that silica is not removed by dams and reservoirs, and that nitrogen levels increase dramatically when agriculture makes up more than 60% of the landscapes feeding into the system.


    In coastal zones, such as the Lake Erie and the Gulf of Mexico, high concentrations of dissolved nitrogen fuel algal growth, which leads to oxygen depletion, or coastal dead zones. In normal conditions, where the ratio of silica:nitrogen is in balance, diatoms — which are effectively the lungs of the planet — are able to survive. Yet, when the chemical balance is tipped towards nitrogen, the phytoplankton community is altered. Diatoms — beneficial algae that we want to see in the Gulf of Mexico — thrive when the levels of silica and nitrogen are in balance. When conditions tend to be more nitrate-rich, other more harmful species of phytoplankton thrive.

    The research team found that an increase in nitrogen runoff from agricultural fields explains why the Gulf of Mexico is continually plagued by harmful algal blooms. The scientists also identified ways in which landscapes could be better managed to improve water quality in the watersheds and coastal zones they feed into. They recommend that landscapes be managed at watershed level to significantly enhance water quality, particularly during wet years. They also suggest that reservoirs and dams could be key areas to target to diminish nutrient loads without impacting silica concentrations of water flowing into the Gulf of Mexico.

    "We need to be vigilant about our land use and water quality," said co-author John Downing, director of the University of Minnesota Sea Grant College Program and the study's principal investigator. "Climate change and increased storminess will likely exacerbate the skewed ratios we found and the extent of harmful blooms in coastal areas if we don't manage agricultural runoff more effectively. Harmful algae blooms cost the U.S. seafood, tourism and health industries over $80 million a year according the National Oceanic and Atmospheric Administration, and we know we can do better."

    Journal Reference

    John A. Downing et al, Low ratios of silica to dissolved nitrogen supplied to rivers arise from agriculture not reservoirs, Ecology Letters (2016). DOI: 10.1111/ele.12689

  • Investing in Water Quality

    Public would rather put money behind funding green infrastructure than gray infrastructure for protecting drinking water sources

    The recent Flint water crisis has driven home the importance of protecting drinking water and the need for investing in and maintaining water infrastructure. Yet policy-makers often find it difficult making decisions on where to invest financial resources and how to gain public approval for spending tax payers money in their efforts to protect drinking water sources.


    Now, a recent study undertaken by researchers at the University of Delaware shows that if given a choice, people would rather see money invested in protecting and conserving water resources with green infrastructure, than money being channeled into gray infrastructure such as water treatment facilities.

    The study, which was published in the scientific journal Agricultural and Resource Economics Review, also found that people's eagerness to contribute to water projects were affected to a large extent by different messages related to global warming, climate change, extreme weather events or decaying water infrastructure.6

    "People are much more willing to pay for conservation," said Kent Messer, director of the Center for Experimental and Applied Economics (CEAE) in the University's College of Agriculture and Natural Resources (CANR), and co-author of the paper. "They like the idea of permanently protecting the waters from their source and avoiding having to do technological fixes."

    The study used a field experiment that involved 251 adults from various sites around northern Delaware, including the New Castle Country Farmers Market, University of Delaware's Ag Day, as well as community members from Southbridge, Wilmington. The participants had to perform one simple task, for which they were financially compensated. They then had the option of donating those funds to one of two organizations that could address water quality issues: 1) the Conservation Fund, which funds green infrastructure projects such as construction of bioswales and other green storm water management options; or 2) the American Water Works Associations (AWWA), which funds gray infrastructure projects. The participants leaned heavily towards contributing towards green infrastructure projects.

    "People didn't just show up and automatically receive money. They earned their money. Then, we asked if they wanted to donate it to either a conservation cause (green infrastructure) or to help drinking water utilities (gray infrastructure)," said Messer.

    The researchers also assessed how different messages influenced the choices the participants made. The results of their survey suggest that people are more likely to contribute when message topics focused on global warming or climate change rather than when messages focused on extreme weather events. Consequently, when formulating a message to encourage citizens to help protect water resources, policy-makers need to choose their message topics carefully.

    According to Messer, policy-makers often debate whether it is wise to discuss climate change or whether this topic is best avoided, focusing on extreme weather instead. Yet this study suggests that may be the wrong approach.

    "This research suggests the emphasis on large storms like Hurricane Sandy will actually make people less willing to take action as it appears that people perceive these large storms as being out of human control," said Messer. "If it's just decaying infrastructure, normal storms, or even climate change, then people might feel they can do something about it. But when you start really emphasizing these large magnitude storms, there becomes a sense of hopelessness."

    Journal Reference

    Sean F Ellis, Jacob R Fooks Kent, D Messer and Matthew J Miller. The Effects of Climate Change Information on Charitable Giving for Water Quality Protection: A Field Experiment. Agricultural and Resource Economics Review, Volume 45, Issue 2 (Economics of Water Quality), August 2016, pp. 319-337, DOI: http://dx.doi.org/10.1017/age.2016.17

  • Testing the Water: DNA Sampling to Detect Water Contaminants

    Water contamination by microbial contaminants is a widespread problem throughout the country. These contaminants make their way into freshwater systems, where they pose a health to humans. While water regulators routinely test water sources for these types of contaminants, the methods used are outdated and unreliable.

    Now, researchers from the Lawrence Berkeley National Laboratory (Berkeley Lab) have found a way to not only accurately detect microbial contaminants in our waterways, but also to distinguish between different sources of those contaminants.


    Using an award-winning device known as a PhyloChip, which is about the size of a credit card, and which can reliably detect more than 60,000 microbe species, water regulators can now test the waters with greater accuracy. During preliminary testing of the device on Northern California's Russian River watershed, the scientists found cases where this new identified microbes that posed a potential health risk to humans that had not been detected by conventional fecal count tests. The study, which was recently published in the scientific journal Water Science, also found that in some cases the conventional testing methods flagged bacteria that were not considered a health risk to humans.

    "With the PhyloChip, in an overnight test we can get a full picture of the microorganisms in any given sample," said Eric Dubinsky, a microbial ecologist at Berkeley Lab and lead author of the paper. "Instead of targeting one organism, we're essentially getting a fingerprint of the microbial community of potential sources in that sample. So it gives us a more comprehensive picture of what's going on. It's a novel way of going about source tracking."

    Local water regulators currently collect water samples, and then culture the bacteria for 12 hours before checking the levels of two key bacteria types: Enterococcus and E. Coli — which are considered indicators of fecal contamination. But this method fails to distinguish between different sources of the bacteria, which could have originated from cattle, waterfowl, humans, sewage or even rotting vegetation.

    "These tests have been used for decades and are relatively primitive," Dubinsky said. "Back in the 1970s when the Clean Water Act was developed and we had sewage basically flowing into our waters, these tests worked really well. Epidemiological studies showed an association of these bacteria with levels of illness of people who used the water. These bacteria don't necessarily get you sick, but they're found in sewage and fecal matter. That's why they're measured."

    While it is easy to identify point sources, such as sewage outfalls, which generally get cleaned up once they have been identified, non-point sources of pollution, such as runoff from agricultural lands, are more difficult to identify, and are becoming a growing concern.

    The PhyloChip, which was developed by co-author, Gary Andersen, a microbial ecologist at Berkeley Lab, together several colleagues at Berkeley Lab, has proven useful for a number agricultural, medical, and environmental applications, including gaining a better understanding of coral reef ecology, air pollution, and environmental conditions in the Gulf of Mexico following the BP oil disaster. The PhyloChip has 1 million probes which enable it to identify microbes according to variations in a specific gene, without the need to culture the bacteria overnight. The scientists soon realized that the PhyloChip held great potential for assessing water quality and pinpointing the source of water contaminants.

    It is no simple task to determine the source of a pathogen. In many cases, more than one type of microbe is needed to determine the source, as the microbial community of animals such as cows can consist of a thousand different microbial organisms.

    To address this, the scientists coerced a lab intern into going around and collecting poop from a wide range of animals. They then set about cataloguing the microbial communities found in the poop specimens of cattle, horses, pigs, raccoons, sea lions, different bird species, as well as other wildlife, humans and sewage, using that catalogue to develop a model which compares an unknown microbial sample with the samples in their reference library.

    "We've used the PhyloChip in a way that it hasn't been used before by using machine learning models to analyze the data in order to detect and classify sources," Andersen said. "It's essentially giving you a statistical probability that a microbial community came from a particular source."

    After comparing their method with forty others used to track sources of microbial contaminants, their method proved to be the only one that could reliably detect all microbial sources correctly. Even when the microbes originate from an animals source that is not listed in their library catalogue, this method can still prove to be extremely useful in identifying the source. For example, in one study the sample was from a chicken, but the team had not yet analyzed chickens. However, they did have records of pigeons, gulls and geese, which enabled them to determine that the sample came from a bird.

    After extensive sampling within the Russian River watershed, which currently does not comply with the Clean Water Act, the scientists discovered that contamination from human sources was widespread around areas where communities depend largely on aging septic tank systems. They also detected significant contamination from human sources following a weekend jazz concert, which was not as clearly evident when using the other methods. Dubinsky attributes this to the fact that this new methods is much more sensitive to human contaminants that the outdated fecal indicator tests.

    The Berkeley Lab scientists are currently working together with the EPA to develop the method further so that it can be used universally at any location, by anyone, even non-experts. The method also holds promise for determining the sources of nutrients that fuel algal blooms, particularly in the Great Lakes, where this continues to be an ongoing problem.

    If you're concerned your water may be contaminated, the Berkey systems equipped with the black berkey filters will remove bacteria and viruses to levels greater than 99.9999%

    Journal Reference:

    Eric A. Dubinsky, Steven R. Butkus, Gary L. Andersen. Microbial source tracking in impaired watersheds using PhyloChip and machine-learning classification. Water Research, 2016; 105: 56 DOI: 10.1016/j.watres.2016.08.035

  • Are Substitute PFOAs a Threat to Drinking Water Quality?

    With the widespread contamination of drinking water by the industrial chemicals perfluorooctanoic acid (PFOA) and perfluorosulphuric acid (PFOS), the US Environmental Protection Agency recently updated their drinking water guidelines for these perfluorinated compounds, issuing a lifetime drinking water health advisory of 70 ppt for human exposure. These chemical compounds are widely used in industry and consumer products, and they persist in the environment, including waterways and aquifers that provide millions of US citizens with drinking water, potentially posing a human health risk.

    One would intuitively believe that regulating the use of harmful pollutants would ultimately have a positive effect on the quality of water. But this is not necessarily the case. Typically, the problem doesn't simply disappear when regulations are implemented, as companies often substitute harmful chemicals with others that have an equally hazardous impact on water quality.


    For example, in the US, the EPA has been working together with large companies such as DuPont in phasing out the use of the hazardous chemical PFOA (),  These are the carcinogenic industrial pollutants responsible for contaminating the drinking water supply of Hoosick Falls and other communities.  This ultimately led to the EPA issuing a health advisory earlier this year. However, according to the water news network, Water Online, DuPont and other companies that use PFOA are highly secretive about the substitute chemicals they are using instead of PFOA, and it is very likely that these replacements are just as hazardous as PFOA itself.

    In an interview on WNYT, Dr David Carpenter, an environmental scientist at the University of Albany, explained:

    "It's been PFOA and perfluorooctanesulfonic acid (PFOS) that's been discontinued, but not the related chemicals that have not been studied so much. The chemicals used to replace these substances present various uncertainties around drinking water quality."

    Carpenter then points out:

    "that the industry is very secretive about what they used to replace PFOA and it's hard to figure out exactly what they are. They're not saying what they replaced it with. It's almost certain that these are perfluorinated compounds (PFCs) with slightly different structures that have not been studied anywhere near the degree that these more common version of perfluorinated compounds have been,"

    According to the WNYT report, the EPA is currently assessing hundreds of alternative substitute PFOA chemicals, and according to an EPA official:

    "There are many reasons to expect a range of toxicities. But more research is needed, particularly on the environmental fate of these compounds to fully evaluate these compounds."

    Ultimately, one has to question whether substituting a known hazardous chemical compound with other chemical compounds (or hundreds of others as may be the case), about which very little if anything is known, offers any benefits in terms of reducing the risk to environmental and human health?

    Note: PFAS's fall under the category of PFC's - Perfluorinated Chemicals. PFOA, PFOS, etc.  The Black Berkey elements that come standard with our Berkey systems do reduce these contaminates.  Berkey water filter PFOA test results can be found here.

  • Drugs in Wastewater Unlikely Crime Busters

    Legal and illegal drugs in wastewater poses both an ecological and human health challenge as they can make their way into freshwater systems and drinking water sources where they can harm wildlife and pose a human health risk. Now, new research shows that wastewater treatment facilities can play a key role in helping to monitor drug usage, and may ultimately help track drug dealers peddling their contraband.

    Swiss scientists recently tested the limitations of using wastewater analysis to crack down on crime. The results of their study was recently published in the journal Forensic Science. The researchers point out that analyzing wastewater to gain a better understanding of drug use is not new — in fact, it even has a name: wastewater-based epidemiology — however, up until now, very little focus has been placed on using this as a mechanism to fight crime. Yet, it can provide pertinent information to law enforcement that can be very useful to help whittle out drug dealers and combat crime.

    water-treatment-plant courtesy: https://www.flickr.com/photos/neesam/4181025893

    Drugs break down within the body, leaving tell-tale traces of metabolites which are excreted as waste. These metabolites can be identified in wastewater, quantified and then back-calculated to determine how much of the drug was originally consumed, as well as provide a good estimate of how many people contributed to the sample. This analysis can provide insight on average drug consumption together with information on changing drug use patterns.

    For the study, which focused on the use of methamphetamine, heroin and cocaine in two Swiss cities, the scientists analyzed wastewater and compared it to information received from police intelligence. To get an estimate of heroin usage in the Swiss city of Lausanne, the researchers measured morphine in sewage wastewater and subtracted the amount that was legally prescribed by medical practitioners. Using this method, from October 2013 to December 2014 the researchers estimated the average daily heroin consumption for the city to be 13 grams.

    During this period, law enforcement officers arrested two drug dealers. After analyzing their phone records and conducting interviews with drug users, it is estimated that between the two of them, the drug dealers supplied around 6 grams of heroin a day — roughly half the market share. This information provided by the wastewater epidemiology supported police intelligence suggesting that unlike methamphetamine and other drugs, heroin is supplied by just a handful of local drug dealers, who police could target effectively.

    As the study so succinctly point out: "You can flush, but you can't hide."

    "Combined with intelligence resulting from police work (e.g., investigations and informants), wastewater analysis can contribute to deciphering the structure of drug markets, as well as the local organization of trafficking networks," the authors conclude. "The results presented here constitute valuable pieces of information, which can be used by law enforcement to guide decisions at strategic and/or operational levels. Furthermore, intelligence gathered through investigations and surveillance constitutes an alternative viewpoint to evaluate results of wastewater analysis."

    The study's findings suggest that for some drugs, the wastewater-based epidemiology can be an effective tool to help law enforcement determine the market share that criminal elements control within the local drug market.

    Journal Reference

    Been, F. et al. Analysis of illicit drugs in wastewater – Is there an added value for law enforcement? Forensic Science International, Volume 266 , 215 - 221; DOI: http://dx.doi.org/10.1016/j.forsciint.2016.05.032

  • Strategies to Mitigate Environmental Damage Caused by Dams

    Throughout the world, dams provide us with essential water supplies needed for drinking, crop irrigation, hydropower and industry. There are around 58,000 large dams, exceeding 15 meters in height, built on rivers around the world. Yet, while these dams provide us with water essential to our survival, and hydropower is seen as a green energy source, the construction of dams on our waterways comes at a significant cost to the environment.

    But managing rivers so that they meet both the needs of human society and that of aquatic ecosystems is a complex challenge. Communities need water as well as power, but building dams on rivers disrupts ecosystem functions and the services these ecosystems provide.


    A recent study conducted by researchers from Utah and Colorado State Universities at Glen Canyon Dam on the Colorado River provides some insight into how to best mitigate the negative impact that dams have on the environment, including proposing a new management method to reduce the impact of hydropeaking — a practice that is commonly used by hydropower dams, which has a negative impact on aquatic food webs further downstream.

    The researchers discuss their findings under the context of increasing global pressure to construct more dams, in a paper that was recently published in the scientific journal Science.

    "Dams change rivers by creating artificial lakes, fragmenting river networks and distorting natural patterns of sediment transport and seasonal variations in water temperature and stream flow," says co-author Jack Schmidt, a professor in the Department of Watershed Sciences at Utah State University, who served as chief of the U.S. Geological Survey's Grand Canyon Monitoring and Research Center from 2011 to 2014.

    Hydropeaking, is the practice commonly used by hydroelectric dams whereby river flows are increased during times of peak electricity demand by consumers. Aquatic insects, which form an essential part of river food webs, are particular vulnerable to the effects of hydropeaking. Insects lay their eggs on submerged aquatic vegetation near the shoreline, but drastic fluctuations in water levels can expose the eggs and/or larvae, causing them to dry out and die.

    "Hydropeaking creates a fluctuating daily pattern of water flows that can severely impair productive shoreline habitats through repeated wetting and drying. A conundrum for river scientists and managers is how to counter these negative effects in a cost-effective manner," says Schmidt. "Managers have to meet customer demand so total elimination of hydropeaking isn't an option. However, we assert that even small adjustments to river flow regimes might help to restore river ecosystems."

    The authors reviewed recent studies that focus on the impact of dams and dam operations on downstream ecosystems, which show how small changes in dam management can have a big positive impact further downstream. For example in a previous hydropeaking study looking at the impact on ecosystems further downstream, the authors suggest "giving aquatic insects the weekend off." Schmidt agrees; by giving insects a two day break from hydropeaking activities, may give them time to recover, which may allow a more natural aquatic food web to re-establish in the river, benefitting fish in the river ecosystem.

    While restoration efforts at existing hydroelectric dams is a good start to addressing the issue, the authors recommend that any new proposed dam project in South America, Asia and Africa should only go ahead after cautious planning and careful consideration is given to their design, location, overall number, and how the proposed new dam will be managed.

    While hydropower is considered a renewable source of energy, it is not always 'green' unless careful consideration is given to the location and operation of those dams to mitigate negative ecological effects.

    "In a world of growing demand for water and energy, we face an increasingly uncertain hydrological future," says Schmidt. "We have to balance economic gain against environmental degradation."

    Journal Reference
    N. LeRoy Poff & John C. Schmidt. How dams can go with the flow. Science; 09 Sep 2016: Vol. 353, Issue 6304, pp. 1099-1100. DOI: 10.1126/science.aah4926

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  • BPA can Reprogram the Brain, Changing Sexual Behavior of Turtles

    BPA is an endocrine disrupting chemical that is used in a wide range of everyday items, including plastic water bottles, food cans and till slips. It is a harmful contaminant that has been associated with many health issues in both humans and wildlife that are exposed to it. BPA makes its way into the environment, and tends to accumulate in aquatic systems where it can negatively impact aquatic wildlife that live there.

    An earlier study conducted by scientists from the University of Missouri-Columbia on painted turtles revealed that BPA disrupts reproductive functioning and can feminize male turtles, causing them to develop female sex organs. In a more recent study, the researchers show how BPA not only physically feminizes male turtles, but it also reprograms the brain, making them exhibit behavioral patterns usually associated with female turtles. The scientists are concerned about the impact this could have on the population status of painted turtles, which could decline as a result.


    According to Cheryl Rosenfeld, an associate professor of biomedical sciences in the MU College of Veterinary Medicine and co-author of this study, the initial study showed that BPA and ethinyl estradiol (EE2), a hormone used in oral contraceptives, could reverse the sex of male turtles, changing them into females.

    "Painted turtles and other reptiles lack sex chromosomes," she explains. "The gender of painted turtles and other reptiles is determined by the incubation temperature of the egg during development. Studies have shown that exposure to endocrine-disrupting chemicals (EDCs), such as BPA, can override incubation temperature and switch the sex of males to females. In our latest study, we found that BPA also affects how the male brain is 'wired,' potentially inducing males to show female type behavioral patterns."

    For their study, the scientists exposed painted turtle eggs to BPA and ethinyl estradiol (EE2) in liquid form, then placed the eggs in an incubator set at a temperature that would typically result in male hatchlings. When the hatchlings were 5 months old the researchers tested their spacial navigation skills to ascertain whether exposure to these chemicals would have any impact on the navigational ability — more specifically, to determine whether their navigational skills would be in line with that expected of females who are better navigators than their male counterparts. The results of the navigational test showed male turtles that were exposed to these hormone disrupting chemicals while still in the egg exhibited better spatial navigational learning and memory skills than male turtles incubated under the same environmental conditions, but which did not get exposed to BPA and EE2 whilst developing in the egg.


    "While improved spatial navigation might be considered a good thing, it also may suggest that when they reach adulthood male turtles will not exhibit courtship behaviors needed to attract a mate and reproduce, which could result in dramatic population declines," explains Rosenfeld.

    According to Professor Rosenfeld, this study is the first to show how these harmful environmental contaminants not only change the physical sexual characteristics of turtles, but affects brain functioning as well. Turtles are considered an 'indicator species' as they can be used to determine the environmental health of the broader aquatic ecosystem. Gaining a clearer understanding of how these endocrine disrupting compounds affect the sexual behavior and orientation of turtles, may enable scientists to better understand the potential impacts of these chemicals on other animal species, including humans.

    The Berkey  water filter, equipped with the black berkey filters, will filter out any BPA that may be in the water.

    Journal Reference

    Lindsey K. Manshack, Caroline M. Conard, Sarah A. Johnson, Jorden M. Alex, Sara J. Bryan, Sharon L. Deem, Dawn K. Holliday, Mark R. Ellersieck, Cheryl S. Rosenfeld. Effects of developmental exposure to bisphenol A and ethinyl estradiol on spatial navigational learning and memory in painted turtles (Chrysemys picta). Hormones and Behavior, 2016; 85: 48 DOI: 10.1016/j.yhbeh.2016.07.009

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    VIDEO: http://www.eurekalert.org/multimedia/pub/122466.php

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