How Water Is Treated for Use in Homes

If you live in a city  . . .

your water comes to you in pipes from a municipal water supplier who gets water from lakes and rivers and sometimes wells, treats it a bit to make it clear, odor-free, germ-free, non-corrosive, and generally palatable, then pumps it through a maze of pipes to your home.

As part of its treatment, the city water plant adds chlorine or a mixture of chlorine and ammonia called chloramine to the water to kill pathogens. The treatment plant also adds other chemicals to clarify the water and prevent corrosion in pipes.  Some cities also add an industrial waste product called fluoride which is believed to prevent tooth decay.

Between the city water plant and the home lie miles of pipe, some of it very old,  made of a variety of materials and in varying states of repair.  The water is affected a lot by pipe materials and by contaminants that can enter the water if the pipe leaks or is broken. The water that leaves the treatment plant is not the same water that enters the home. A lot of things happen to it along the way.

Most city water plants do a praiseworthy job of taking some pretty dirty raw water from a lake or river, getting the mud and sticks out of it and turning it into water that looks clear, tastes good, and won’t cause a cholera epidemic. They supply water that is of really high quality for hosing down driveways and flushing toilets. People who have watched a plumber cut open a pipe entering their home, however, usually don’t feel good about drinking their tap water anymore, or even bathing in it.

This very decent water delivered by the city can be made excellent in the home, which is, after all, where the fine polishing of water should take place. Home treatment makes much more sense than trying to supply top quality drinking water for flushing toilets and mopping floors.

Point of entry treatment for city water most often consists of cartridge or tank-style activated carbon filters to remove disinfectants (chlorine or chloramine).  If the water is “hard” (meaning that it has lots of calcium and magnesium in it), it can be treated with a conventional water softener or one of the several newer “salt-free” alternatives. Treatment for hardness is mainly done to protect pipes and fixtures and to make water more aesthetically pleasing.  Adding a point-of-entry ultraviolet (UV) unit to assure bacteria-free, cyst-free water for the whole home is becoming more popular, especially in light of the increasing number of “boil water” alerts.

For point-of-use treatment for the water that you’re going to drink, cook with, or make ice with,  a variety of countertop and under-the-sink systems are available, from simple, very tight carbon filters that improve taste and odor and remove chemicals to the more comprehensive treatment, reverse osmosis. The real king of point of use drinking water systems is reverse osmosis.  A good undersink reverse osmosis unit can provide top quality drinking water for a moderate cost.  RO, as it’s called, removes virtually anything one would want removed from water, including the more difficult contaminants like arsenic, lead, chromium 6, fluoride, chloramines, trihalomethanes, and a wide range of pesticides, herbicides, “pharmaceuticals,” and so-called “emerging contaminants.”

If you live outside the city  . . .

your water usually comes  to you from a well on your own property. A well is essentially a hole in the ground with a pipe through which water in an underground pool is sucked up to the surface. It’s like drinking from a glass with a drinking straw. Also,  many non-city dwellers pull their water through pipes directly from a pond or stream and treat it themselves.

If you have a well or draw water from a lake or river, you are your own water treatment superintendent, so you need to pay attention to what you’re about. The first thing you should do is get a good, comprehensive water test. This will cost you a couple of hundred dollars, but it will pay for itself easily in what you’ll save by not purchasing unnecessary or inappropriate equipment. If the test shows that your water  is perfect, the peace of mind you gain will pay for the test.

The reason the well test is needed is that you don’t have the benefit of the testing that’s done for you with city water. If there’s arsenic in the city’s water source, the city is obligated to take care of it and to tell you about it. If there’s arsenic in your well, the only way you’ll know is by having a good test done.

With private water sources there is a much greater chance that extreme treatment will be needed. Here are some of the common issues with well, river and pond water, along with some of the ways they can be corrected.

Bacteria — pathogens like E. coli can be controlled by chlorination or ultraviolet treatment.

Iron and manganese— treated with iron filters that often require pre-treatment with aeration or chlorine. Small amounts of iron and manganese can also be treated with a water softener.

Hydrogen Sulfide (rotten egg odor) — treated by chlorination or aeration followed by filtration.

Arsenic, Chromium — reverse osmosis for drinking water. (Frequently left untreated for point of entry.)

Pesticide, Herbicide, general chemical contamination –Carbon filtration.

Tannins (tea colored water) Ion exchange and carbon filtration.

Sand, Sediment — Backwashing or cartridge style sediment filters.

Dissolved Solids (high mineral content) — Reverse osmosis.

Whether your water comes from a city, a lake, or your own well, an undersink reverse osmosis unit is your most complete drinking water option.

Lakes are getting dangerously salty, and it’s our fault

by Mary Beth Griggs

Salt. You might be happy to have it in your pasta water and your oceans, but in your friendly neighborhood freshwater lake, it’s an unwelcome intruder.

Unfortunately, salt is butting into lakes more and more frequently as humans move closer and closer to lakes, pouring increasing amounts of salt on the roads in the winter. In a study published Monday in PNAS, researchers looked at 371 lakes scattered across the northern United States and southern Canada from Minnesota and Michigan to Maine and Ontario, an area known as the North American Lakes Region.

The researchers scoured public records to find relatively large lakes (covering about 10 acres) with 10 years worth of data about the water body’s chloride levels. Then they looked at the area surrounding the lake to see how many roads were nearby. If even one percent of the land surface within a buffer zone extending 1,640 feet from the lakeshore was paved, then the lake was extremely likely to have rising salinity levels.

“Lakes are really good at showing long term environmental change,” says lead study author Hilary Dugan. Unlike rivers, which tend to show salt contamination in steep spikes, lakes show a steady change over time.

Many kinds of salt used on roads are chemically similar to table salt—NaCL—or sodium chloride. The presence of salt messes with water’s ability to freeze into a slippery, icy layer on the roads in winter. But when the weather warms, all that salt gets washed off the impervious road surfaces, sidewalks, and parking lots. It ends up accumulating in the soil, and eventually getting washed out by rain and snowmelt into surface waters like lakes and streams as sodium and chloride components.

Just like having too much salt is bad for you, too much chloride can be bad for the environment. It can kill off plants, and make waters less hospitable for native plants and algae.

Salt becomes noticeable in drinking water at about 300 milligrams per liter, or one teaspoon of salt in five gallons of water, says Dugan. That’s when you start tasting the difference, and it’s around that concentration that salt starts to put stress on freshwater plants and animals, which have adapted to live in extremely fresh water.

Road salt impacts the environment in other ways as well. While on the road, it can attract salt-loving animals like deer, increasing the possibility of both roadkill and traffic accidents.

Chloride can also make water more corrosive. In Flint, Michigan, researchers found that the chloride from road salt made the water in the Flint River so corrosive that when the city switched water sources, the water ate away at the lead pipes, creating the ongoing water crisis.

But there is still hope.

“The good news is that we can always improve water quality,” Dugan says. Unlike phosphorus or other pollutants that can lurk in sediments in a lakebed for long periods of time, chlorides stay in the water column, and can gradually be flushed out of a lake as new water enters the lake. “If you improve the water going into a lake you have the potential to freshen the lake,” Dugan says.

Daunted by the rising price of salt, governments have already started to adopt more conservative salt-use measures, only using the amount necessary to ensure public safety. But homeowners can help cut back too. A single 12 oz coffee cup is all you need to salt a 20-foot length of driveway. Dugan also recommends only salting at temperatures that you know will be effective. Below 15 degrees Fahrenheit, dry salt on a surface is useless, and won’t prevent ice from forming.

Dugan says that while this is the largest study of its kind—analyzing salinity levels in lakes across a broad region—there are still plenty of questions to answer, including what happens over time as conservation measures are put in place, and people start using less salt.

We started sprinkling salt on the roads back in the 1940’s and have kept at it ever since. That’s tons of salt lurking in the environment, in soils and other surfaces. Even if we start making changes to how we handle winter weather, it will take awhile to get all that salt out of our systems.

Source: Popular Science.

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Mercury Levels in Great Lakes Fish Is on the Rise

The amount of mercury found in fish tissues has dropped steadily over decades since the 1970s. That corresponded with the reduction of pollution coming from Midwestern smokestacks as regulations tightened, pollution prevention technology improved, and coal-fired factories and power plants went offline.

But over the last several years, that started changing. Scientists are finding mercury levels rising in large Great Lakes fish such as walleye and lake trout. Curiously, it’s occurring with fish in some locations but not others. Researchers are still trying to figure out why.
The mercury levels are not surpassing U.S. Environmental Protection Agency thresholds. But researchers want to determine if what they are seeing is a temporary trend or a trajectory that’s only going to worsen.
Mercury is a heavy, silvery metal, unusual in that it’s liquid at room temperature. It’s naturally occurring, but is rare to find uncombined with other elements. It is toxic to humans and animals — and unlike many other toxins, mercury remains in the environment for very long periods of time, moving up the food chain and compounding inside animals that ingest it. The EPA has found that mercury in water has the potential to cause kidney damage from short-term exposures at levels above the maximum contaminant level of just 0.002 parts per million. Mercury can inhibit brain development in fetuses and children, and harm immune systems and adult heart function.

Many types of mercury in the environment tend to pass through fish when ingested. But a type known as methylmercury tends to be absorbed into fish tissues. As small fish eat contaminated insects, and medium-sized fish eat the smaller fish, and large game fish eat the medium fish, those mercury concentrations get magnified exponentially, a process known as bioaccumulation.

Although reasons for the gradual but steady increase in mercury in Great Lakes fish are unclear, the leading theory ties the increase to gradually warming water temperatures. Also climate change has resulted in a lot of flooding which causes re-suspension of sediments. What was buried can become exposed, increasing the availability of mercury in lake water. Invasive species such as the zebra and quagga mussel population which change the diet of lake fish are also suspected as a cause of rising mercury levels.

The need for continued close monitoring of mercury levels in the lakes is critical, and this comes at a bad time in light of  President Trump’s 2017 budget proposal that calls for elimination of virtually all Great Lakes restoration funds.

Excerpted from USA Today.

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Are US Dams Safe?

Dam disasters have been rare but spectacular.

The recent scare at the Oroville Dam in California has brought dam safety to public attention. The following is adapted from a piece by Jeremy P. Jacobs.

The catastrophic failure of the South Fork Dam in 1889 killed more than 2,200 people in Johnstown, Pennsylvania.

There have been many U.S. dam failures. And some have been catastrophic.

In May 1889, the 72-foot-tall South Fork Dam on western Pennsylvania’s man-made Lake Conemaugh gave way, unleashing a 40-foot wall of water that hit the city of Johnstown, nearly 9 miles away. More than 2,200 people were killed–that’s 1 out of every 5 Johnstown residents.

And in California, the St. Francis Dam was considered an engineering feat in Los Angeles County until it failed in 1928, killing as many as 400 people.

The Baldwin Hills Dam, also in Los Angeles, gave way, killing five in 1963. In 1976, the Bureau of Reclamation’s Teton Dam in eastern Idaho collapsed, killing 11 and causing more than $1 billion in property damage.

The most recent dam failure to cause a fatality occurred in 2006, when the earthen Ka Loko Dam in Kauai, Hawaii, breached, killing seven people.

Some experts caution against making too much of the number of fatalities linked to dam failures.

Martin McCann of Stanford University’s National Performance of Dams Program said that since the 1850s, dams have killed probably a little more than 4,000 people — a large number, but one that pales in comparison to auto accidents, for example.

“If your argument were to be based on body counts, crocodiles and deer running on highways might beat out dams,” McCann said.

He noted that dam inspections and state and federal authorities have improved, especially since the 1970s when fatalities from dam failures peaked at more than 450 in the decade.

“It’s not black and white. Do we have a lot of dams that pose a risk to the public? Yeah, we do,” he said. “Are they all in terrible shape? Not even close.”

Reference source:  E & E News.

Current Water News

by Hardly Waite

In the ongoing state vs. state water wars being waged in the courts, Georgia won a major decision over Florida and Texas won over New Mexico. Both cases involve the right to water in rivers that pass through both states.

In a more complex litigation about water, the Trump administration (as did also the Obama administration) is asking a federal court to dismiss a lawsuit by New Mexico and the Navajo Nation over a 2015 mine-waste spill caused by the Environmental Protection Agency (EPA) at the abandoned Gold King Mine in Colorado.  There are 1.2 billion in claims, and the government is denying responsibility because the agency was simply aiding in cleanup caused by operators of the mine. Republicans earlier slammed the Obama administration for taking the same stance as the current administration.

The 2015 spill was caused by an EPA contractor who, working with federal and state employees, miscalculated the pressure of wastewater at the abandoned mine. About 3 million gallons of toxic sludge spilled out, turning the Animas River orange for days, along with downstream rivers that run through New Mexico and the Navajo Nation’s reservation.

New Mexico has also sued Colorado in the Supreme Court over its alleged responsibility for the spill. The high court is considering whether to hear that case.

Other Water News

New York city’s need for water infrastructure upgrade is expected to cost $80 billion over the next 20 years.

Oklahoma is considering joining the practice of several other states of storing water underground by using “leaky ponds” to recharge aquifers. Rather than allow surplus water to leave the state as runoff to rivers or to be stored in lakes subject to loss by evaporation, water is redirected to aquifers to be pumped to the surface in times of need.

Good News for Lake Mead, and Consequently Las Vegas: Federal forecasters now expect the Lake Mead reservoir to avoid its first federal shortage declaration next year, thanks to the boost it should get from what could wind up as the wettest winter on the river’s basin in 20 years. Storms in Utah, Colorado and Wyoming over the past month have added more than 3 million acre-feet to the water supply forecast for the Colorado. That’s a 10-year supply for Nevada, which gets 300,000 acre-feet from the river each year.

There is a rather extensive research project going on at the University of Michigan that is designed to find the most effective ways to convert urine into fertilizer that can be used to help plants grow. Urine is rich is nitrogen, phosphorous, and potassium. The current phase of the project features uses of a special toilet that harvests fertilizer ingredients from human urine.

Although reservoirs are seldom thought of as part of the water infrastructure that needs maintenance, water managers are catching on that many of the nation’s reservoirs are operating at a fraction of their original capacity because they are filling with silt, sand and gravel. Evidence is growing that cleaning the debris out of our reservoirs to restore their holding capacity makes more sense than searching for new sources of water by building dams and drilling more wells.

Gazette’s Famous Water Picture Series: The Lake Berryessa Glory Hole

Lake Berryessa Glory Hole

Lake Berryessa is the largest lake in Napa County, California. The reservoir in the Vaca Mountains is formed by the Monticello Dam, which provides water and hydroelectricity to the North Bay region of the San Francisco Bay Area.

What you see in the picture is the dam’s spillway, which because of California’s drought had not overflowed for a long, long time. After a drought-ridden 10-year period, in February of 2017 water finally spilled into Lake Berryessa’s Glory Hole, bringing an end to the longest gap between spills in the lake’s history.

The Glory Hole is near the dam on the southeast side of the reservoir. It is an open bell-mouth spillway, 72 feet in diameter. The pipe has a straight drop of 200 feet,  and the diameter shrinks down to about 28 feet. The spillway has a maximum capacity of 48,000 cfs (cubic feet per second).  One cubic foot per second is about 450 gallons per minute, so the Glory Hole’s capacity to drain the lake is about 21 million gpm.  The spillway operates when there is excess water in the reservoir. In 2017 after heavy rains it started flowing, for the first time since 2006.

In 1997 a woman was killed after being pulled inside the spillway.

The Glory Hole when it isn’t overflowing

History of Ultraviolet Water Treatment

Although UV has other applications in water treatment, such as chloramine reduction, by far the most common use is for germicidal disinfection. As the picture illustrates, the standard UV dosage for germicidal treatment is 254 nanometers.

Although it’s taken a long time for the technology to become widely adopted, UV has been around for a long time. In 1877, the germicidal properties of sunlight were discovered and it was only a matter of time before people tried to apply this knowledge for practical use. In 1903, Niels Fensen received a Nobel Prize for his use of ultraviolet light to combat tuberculosis, and in 1910, the first drinking water disinfection system opened in Marseilles, France.

From that time, the technology changed very little until the 1930s, when the first tubular lamps were developed. The tubular lamp allowed for easier applications and different configurations for use. In the 1950s, the first truly significant research into UV disinfection began. By the 1960s, UV disinfection was becoming more widely used in commercial applications and was creeping into the residential market.

Today, ultraviolet disinfection is widely accepted as an effective treatment for the removal of microbiological contaminants from water. Although it was initially viewed as a treatment for un-chlorinated well water, the use of UV for city water residential applications is increasing rapidly. As the infrastructure that cities use to deliver water to customers deteriorates, point-of-entry UV is expected to become a standard feature in homes.

Even highly chlorine-resistant microbes such as Giardia and Cryptosporidium can be effectively eliminated from water with UV. UV systems are becoming an increasingly popular alternative to chemical treatment for many applications.

Reference: Viqua.

See also,  The Basics of UV Water Treatment.”

Compact Whole House Cartridge-Style Filter Installation

Compact Whole House Filters Installed in Series.  Water passes through the sediment filter and then through the carbon block filter.

An extremely versatile product,  Pure Water Products’ Compact Whole House Filters can be installed in series, as shown above, or in parallel, as shown in the picture below.

Parallel Installation gives double the flow rate potential. Two cartridges capable of handling 7 gallons-per-minute each become a 14 gallon-per-minute filter when the water line is split so that each filter handles half the flow.

Installation with sediment prefilter (right), split to two carbon filters, then coming together to feed water softener (left).  (Click picture to enlarge.)

As the pictures show, even our multi-filter systems are sold for mounting on single brackets. This is a great advantage for the installer. The flow can be directed either right to left or left to right, the bracket can be pointed up or down, and multiple units can even be installed in separate locations, when space is tight. The filters can also be installed either in series (first picture) or in parallel (second picture).

The “20 inch Big Blue” housing accepts 4.5″ X 20″ cartridges, a standard size, so many filtration options are available.  The housing works with radial flow cartridges, where water flows from the outside of the cartridge to the center (carbon block and sediment filters) or axial flow cartridges, where water flows the full length of the cartridge from bottom to top (“media” cartridges with granular carbon, iron removal media, KDF, softening resin, pH amenders, etc.).

The Pure Water Products Compact Whole House Filter comes with housing, one filter cartridge, mounting bracket with screws, and a filter wrench for cartridge replacement.

Typical applications of this filter are for whole house city water treatment of sediment, chlorine, chloramines, taste/odor, and extraneous chemicals, or well water treatment of sediment, low pH, iron, manganese, odors, and scaling.

Compact units are easy to install, needing no drain or electrical connection, inexpensive, and versatile. The standard pipe size is 1″, but they are available also in 3/4″ and 1.5″ sizes.

Cartridges that will fit our Compact Whole House systems.

Compact Whole House Filters

Backwashing Filters with 4″ Top Holes

Fleck 2815 Filter, 21″ X 62″.  Will support a service flow of up to 50 gallons per minute.

Most residential backwashing filters have 2.5″ threaded top holes in the mineral tank. Conventional “small” filter valves like the Fleck 5600, Fleck 2510, and Fleck 5810 screw into 2.5″ top holes.  These control valves can be used on tanks up to 13″ in diameter.  Beginning with 14″ tanks, most have 4″ top holes and require the use of larger filter valves, like the Fleck 2750, 2815, or 3150. (Note: Fleck 2815 was formerly 2850. Fleck 2850 is no longer available.) Tanks with 4″ holes are available up to 24″ X 72″ in size. (The next larger size of tanks have a 6″ flange connection on top rather than a threaded hole.)

For want of better name, we call the filters made with the second size top hole 4″ filters. The filter above is from this group.

In general terms, filters of this size are for use in situations needing flow rates above 10 gallons per minute. Here is a chart that gives some typical uses with maximum effective service flow rates, in gallons per minute (GPM).

Be aware that there can be great discrepancies among media when it comes to service flow rates and backwash requirements.  For example, Turbidex will support a much higher service flow rate than Filter Ag.

Big Filter Prices

Prices of filters given below include control valve (mechanical timer), Structural Mineral Tank, Drain Line Flow Control, Riser with upper and lower baskets, media funnel, and gravel underbed. We pay shipping to lower-48 addresses. Usual lead time is about 4 days. These filters all have the standard electro-mechanical timer. Electronic SXT andNXT2 controls are available on some models at a slightly higher price.  Please inquire.  Important note: pricing on these units is now all “call to order.” We now also have Nelsen C-Series filters in most of the same sizes. Call for pricing and availability.

Prices above are for the filter only. Gravel underbed is included, but not filter media.

Filters may be ordered with or without media. If media is purchased with the filter, the filter will be set up to match the media. If no media is ordered, tell us your intended use for the filter and we will equip the filter with an appropriate flow control device. There is no pre-shipment setup of control valves with the these filters, but we can suggest and help with setup after the purchase.

Filter Media, Prices can be found on our main website, here.

Media available for these filters:

Granular Filter Carbon, for Chlorine, Chloramine, Chemicals, Taste & Odor, Color

Standard Bitumious

Coconut Shell

Centaur Catalytic

Aquasorb (Jacobi) Coconut Shell Catalytic:

Colorsorb Lignite

Iron, Manganese, and Hydrogen Sulfide

Birm

Katalox Light

Filox

Sediment and Precipitated Iron:

Filter Ag

Zeolite (Turbidex)

Multi-Media (garnet, sand, anthracite)

For size comparison, a 21″ X 62″ filter (10 cubic feet of media) beside a 10″ X 54″ filter (1.5 cubic feet of media).

These filters can be ordered by calling 888 382 3814.