Pure Water Occasional, February 14, 2021 |
Good News Sometimes Follows Bad
Water use in the United States is forecast to decline 1.1 percent per year in volume through 2024, according to a new report. The COVID-19 pandemic in 2020 is expected to reduce water use in power generation and manufacturing establishments due to the contraction in manufacturing shipments and electricity generation. The nation's water use is expected to see a 5.1 percent annual drop from 2019 levels.
Also in the "good news" column: Covid-19 lockdowns led to a significant drop in global warming pollution. Yale Climate Connections.
California's largest lake, known as the Salton Sea, is twice as salty as the ocean. It is being starved for water, and as it recedes, it creates a formidable air pollution problem by exposing decades of buildup of agricultural chemicals to the desert wind. "The Salton Sea’s shoreline is receding, exposing a dusty lakebed known as the 'playa.' This sandy substance holds a century’s worth of agricultural runoff, including DDT, ammonia, possibly carcinogenic herbicides like trifluralin and other chemicals. Its windborne dust travels across Southern California and into Arizona, but nearby communities — many of them populated by Latino farmworkers — bear the heaviest burden. "
Read the story of California's so-far ineffective effort to fix the Salton Sea. Grist.
The Bloomberg Billionaires Index named Zhong Shanshan, the chairman of Nongfu Spring Co., a bottled-water company in China, the world’s sixth richest person.
Ethanol is supposed to be an environmentally friendly substitute for gasoline, but one Nebraska biofuel plant has been identified as the source of staggering amounts of "neonic" contaminants like clothianidin and thiamethoxam in area waters. The Guardian.
Former Michigan governor Rick Snyder has been charged with criminal "neglect" in regard to the Flint water crisis. NY Times.
Saxton Borough (PA) is spending $75,000 to replace 32 filters at its water treatment facility. The filters last about seven years.
The Bureau of Reclamation’s dire projections for Colorado River Basin reservoirs for the first time has triggered drought contingency planning across seven basin states. The Bureau of Reclamation’s quarterly report was dire, showing Lake Powell at 42% of capacity and downriver Lake Mead at 40% capacity. The Colorado Sun.
Solar Desalination Dome being built in Saudi Arabia harvests fresh water from the sea with zero energy use, zero waste.
A new desalination technique known as Solar Dome technology is being developed for use in Saudi Arabia. Developed in the UK at Cranfield University, the dome is claimed to be a 100 per cent carbon neutral system. It works by piping seawater under a glass-enclosed dome where it is super-heated by focused mirrors. No waste is returned to the ocean. The concentrated brine that collects at the bottom of the device is recycled for use in lithium batteries, road salt, detergents and fertilizer. Details and video: AquaTech.
One person died and 33 were hospitalized by a diarrhea outbreak caused by a contaminated water well in a town in the Phillipines. Phillipine News Agency.
For a first person account of what it's like to drink a gallon of water every day, read Ana Suarez' SF Gate piece. As you might guess, it's mainly about how to organize your life around peeing.
Deepest Lake in the US?
The deepest lake in the US, Crater Lake, the centerpiece and namesake of the only national park in Oregon, goes down to depths of 1,943 feet—that's enough room to stack three-and-a-half Washington Monuments on top of each other. Fed mainly by snowfall, this pristine, crystal blue lake came into the world with a bang. It is believed that sometime around 5700 BCE, Mount Mazama erupted, losing roughly 3,000 feet of its height. The volcano blew out so much molten rock that it left a giant depression that gradually filled with water, giving us the deepest lake in the US.
|
The link above connects you with an incredible amount of water treatment information. It indexes the main product areas on Pure Water Products' main website and provides categorized links to the 1,500 plus water treatment articles on the Pure Water Gazette site.
Within this listing are links to the alphabetized Water Treatment Issue index on the PWP website and the extensive water treatment article archive on the same site. You will also find a back issue index to the scores of back issues of the Pure Water Occasional.
We invite you to browse. The good thing is that you will not be bombarded by pop-up ads or otherwise molested. Our aim is to provide a very considerable amount of useful information and to keep it simple and ad-free.
|
FAQs
This section always includes actual questions received since the previous Occasional and our actual answer.
|
Question:
What would my waste to product water ratio be if I was using a 100 GPD membrane and a 200 ml flow restrictor?
Is there a formula to determine that?
Answer:
Yes, there is a formula to figure the ratio. But the answer to the question is, no, you shouldn't use a 200 ml/m flow restrictor with a 100 gpd membrane.
To figure the ratio you have to get the membrane and the flow restrictor into the same unit of measurement. Membranes are usually measured in gallons produced per day and flow restrictors in milligrams per minute. The easy way to compare them is to multiply the restrictor size by 0.38 to convert the milliliters per minute to gallons per day. Two hundred ml/m equals about 78 gallons per day. This means that the combination you asked about would run 76 gallons of water to drain in 24 hours of continuous operation and it would produce 100 gallons of permeate, or product water, during the day. This doesn't provide nearly enough rinse water for the membrane, and the membrane would have a short life and produce lower quality water. The drain water, or brine, is as important as the product water. Its function is to wash away the contaminants that the membrane has rejected and to keep the membrane clean.
Here's a chart of recommended membrane/flow restrictor matchups from our website. This isn't to say that these can't be violated, but for undersink RO units running on tap water these are in the ballpark of what most RO makers use. New high super saving membranes, like the Pentair GRO, are exceptions. a 50 gal. per day GRO, for example, can be paired with a 150 ml/m restrictor.
| Membrane Size | Use Flow Restrictor |
| 18 gpd |
200 |
| 25 gpd |
250 |
| 36 gpd |
250 or 360 |
| 50 gpd |
420 or 525 |
| 75 gpd |
525 or 800 |
| 100 gpd |
800 |
Question:
Hello! I would like to grab one of the Pura UV20-3 systems for our boat, but the left to right direction will result in quite a bit of awkward and unnecessary plumbing. Is it possible to reverse the bracket on the top (does it have the UV hole drilled on both sides, or could I just drill out that hole?) such that I could have the filters run right to left to have the UV at the end?
Answer:
That's an issue with Pura, and there isn't an easy answer. I'm not saying you can't turn the unit and drill an extra hole in the mounting bracket, but it would require pretty precise placement of the hole. The "awkward and unnecessary plumbing" solution you mention is probably the safest way and way most people deal with the problem.
Here's an alternative. We also have Viqua UV units. They are built on a U-Shaped bracket to allow easy installation from either direction. The Viqua VH200 series, with the same dosage intensity as the Pura unit, comes in either single UV or UV with one 4.5" X 10" filter and it's very easy to add another filter in front of it (a lot easier than trying to do the awkward plumbing with the Pura).
Here's a page that explains and has one alternative suggestion to add the second filter.
The Viqua with an added filter costs a few dollars more but is, I think, a much better solution.
|
Glyphosate (Round Up) in Water
|
Glyphosate, known better as Roundup and sold under several other brand names as well, a product of Monsanto, has been around since 1974. It is a potent and popular herbicide, registered for use in 130 countries. The world consumes more than 720,000 metric tons annually, so there is plenty to get into water. Glyphosate was detected in 36% of stream samples from 9 Midwestern US states as far back as 2002.
Although Roundup has always been viewed with suspicion, there had been little evidence that it poses a cancer risk to humans. Recent studies, however, have shown mixed results. Currently, the EPA sets its MCL at 700 parts per billion. The World Health Organization has for years insisted that regulatory guidelines are not necessary because Glyphosate poses low risk in drinking water.
Despite such assurances, most prefer not drinking Roundup. There are many options for getting rid of it. These include chlorination, ozonation, nanofiltration, reverse osmosis, and filtration with granular activated carbon.
Reference: Water Technology magazine, July, 2016.
Gazette Afternote: In August of 2018, a California jury found Monsanto liable in a lawsuit filed by a man who alleged the company’s glyphosate-based weedkillers, including Roundup, caused his cancer and ordered the company to pay $289 million in damages.This case has certainly cast doubts on the “low risk” assessment. As early as 2015, the World Health Organization’s cancer arm classified glyphosate as “probably carcinogenic to humans.”
Gazette Afternote 2: In June 2020, Roundup maker Bayer AB announced a blockbuster $10 billion dollar settlement to resolve cancer lawsuits connected to its weedkiller Roundup. This after Bayer faced tens of thousands of claims linking the active ingredient in RoundUp– glyphosate– to increased risk of developing Non Hodgkins Lymphoma.
The lesson here, of course, is that experts, including the World Health Organization, don’t always get it right. It is always best to err on the side of caution. Having a good drinking water system in the home serves as protection against mistakes by the experts.
|
Bacterial Growth in Water Heaters
Which Heaters are Safest, and What’s the Ideal Temperature?
|
What Are Chlorine Burns?
by Pure Water Annie
Gazette technical wizard Pure Water Annie addresses the perplexing questions about water treatment.
|
Once a year, usually in spring, water suppliers that normally disinfect their product with chloramine, a mixture of chlorine and ammonia, perform a cleaning procedure known as a “chlorine burn.” The purpose is simply to clean out the pipes, ridding the distribution system of film and debris that has built up.
The clean-out is accomplished by simply switching disinfectants from chloramine to straight chlorine for a time, and usually upping the dosage a bit to speed things along. Compared with chlorine, chloramine is a rather weak disinfectant. Its weak performance allows sludge and scum, bacterial film, to build up in pipe walls and crevices. The yearly purge, or “burn,” with straight chlorine cleans things out.
Chloramine is substituted for chlorine as the regular disinfectant in an increasing number of city water systems. The switch from chlorine to chloramine has been going on over a number of years as suppliers seek ways to stay in compliance with EPA standards for DBPs, disinfection by-products, that are produced as a consequence of chlorination. Some DBPs are known carcinogens, and EPA requires suppliers to monitor them. Chloramine, a weaker disinfectant, does not produce DBPs.
Are chlorine burns a good idea? Good or bad, they are necessary, since without a periodic cleanout, buildup in pipes would create significant problems for the water system. The practice does call into question, however, the wisdom of using chloramine rather than chlorine in the first place, since, as many argue, the burn and subsequent purging of pipes creates elevated levels of disinfection by-products in the system and higher than normal chlorine discharge into lakes and streams. In other words, for a short time we get concentrated doses of disinfectants and byproducts, which may be worse than what we would have with chlorine as the regular disinfectant.
The moral: With a good carbon filtration system in your home, you won’t even know when the burn takes place. The elevated chlorine levels, murky water, and dislodged sediment that your neighbors are complaining about, you won’t even notice.
|
PFAS exposure linked with worse COVID-19 outcomes
|
People who had elevated blood levels of a toxic chemical called perfluorobutanoic acid (PFBA) had an increased risk of a more severe course of COVID-19 than those who did not have elevated levels, according to a new study led by Harvard T.H. Chan School of Public Health. PFBA is part of a class of man-made chemicals known as perfluorinated alkylate substances (PFASs), which have previously been shown to suppress immune function.
The study, published December 31, 2020 in PLOS ONE, was led by Philippe Grandjean, adjunct professor of environmental health.
PFASs have water- and grease-resistant properties and are used in a wide variety of products, including nonstick cookware, waterproof clothing, food packaging, and firefighting foams. PFBA, more than other PFASs, is known to accumulate in the lungs, according to the study.
Researchers looked at PFAS levels in blood samples from 323 Danish individuals infected with the coronavirus. They found that those with higher PFBA levels had higher odds of being hospitalized, winding up in intensive care, and dying than those with lower levels.
The findings suggest that further study is needed to determine whether elevated exposures to other environmental immunotoxicants may worsen COVID-19 outcomes, the authors wrote.
|
Places to visit for additional information:
|
Thanks for reading and be sure to check out the next Occasional!
|
|
|
|  | |
