A Practical Guide to Sizing Whole House Water Filters

by Gene Franks

One of the critical factors in determining the size of a “whole house” water treatment system, whether you are removing iron from well water or chemicals from city water, is the rate of service flow you need. To work effectively, the filter must be large enough to handle the volume of water, in gallons per minute (gpm), that you plan to run through it.  Undersizing reduces water pressure, shortens the life of the filter, and compromises quality.

To get a general idea of your service flow requirements, you might refer to this standard sizing chart:

The problem starts when you look at a chart of flow rate recommendations for the various filter media. If you have a family of four, for example, and live in a home with two bathrooms, you’ll see from the chart above that you need to size your filter for a 7 gallon-per-minute flow rate. However, if you plan to purchase a Birm filter to remove iron from your well water, the flow rate chart will tell you that a 13” X 54” filter would provide a service flow rate of only 3.9 gallons per minute and even a massive 16” filter would give you only a 5.9 gpm service flow. Note also that to backwash the 16” filter you would need 15.4 gpm, which your well probably isn’t capable of.

Faced with this dilemma, you could install two 13” filters side by side so that each has to handle only half the service flow. This gives you almost 8 gpm. If you backwash the filters separately, they would need only 10 gpm, which your well will handle.

Should you use the two 13″ filters installed in tandem? Probably not, unless your home requires long, sustained service flow rates, and this rarely happens in residential applications.  The reality is that even though 7 gpm is a good figure to keep in mind, most residential water use is at the rate of two or three gallons per minute. It’s also true that you can over-run the recommended rate limit now and then without fear of getting arrested.

The imaginary family of  four in a two-bath home, in fact, usually gets by very well with a 12” X 52” or even a 10” X 54” Birm filter. And it really helps if you use common sense and arrange things so that a dishwasher, a clothes washer, and a shower aren’t in use at the same time. Briefly violating the “speed limit” with an occasional burst of 7 gpm usually doesn’t result in a noticeable bad result.

Chloramine Filters

Among the most troublesome sizing problems are chloramine filters for city water users. Chloramines are hard to remove and require a slower flow rate than chlorine. Recommended flow rates for Pure Water Products’ “Chloramine Catcher,” for example, which were based on  the catalytic carbon maker’s flow rate recommendation, allow only 6.25 gallons per minute for a 13” filter. It would be common, nevertheless, for the hypothetical 7-gpm family to use a 10” X 54” filter, which is recommended for a flow of only 3.25 gpm.  Usually a  12″ X 52″ chloramine filter will perform excellently in this situation.  Going over the recommended rate from time to time might allow less-than-perfect performance from the filter (probably not noticeable), or it might shorten the life of the carbon a bit, but it won’t break anything or get you arrested.

Realize that irrigation doesn’t fall under to the 7 gpm rule. If you plan to run water for hours on end from your well and don’t want iron to stain your driveway, you’ll need to find an alternative solution. The two 13” filters we discussed above won’t handle it.  In fact, filtering water for lawn irrigation and filling large swimming pools fall under a whole different set of rules.

Keep in mind, too, that if you are filtering water for a sustained flow to a dialysis machine or feeding a fish pond with many gallons of water from a chloraminated source, you are advised to follow the rules strictly.

It is easy to provide sufficient service capacity with cartridge-style filters by using them in tandem.  In the installation above, the installer has split the service flow so that each of the filters with a 5 gpm capacity is handling half the service load.  More about this.

Unholy pollution in India’s holy waters

By Victor Mallet in Varanasi

For foreigners and Indians alike, the shocking state of the Ganges is an enduring mystery. If the river is so holy, why do the 450 million people who depend on it for water and food treat it with such contempt?

There cannot be many high priests who understand sewage treatment technology, but in the holy Hindu city of Varanasi it makes sense: every day thousands of devotees bathe in the Ganges from the steps of the city’s famous ghats, convinced not only of the sanctity but also of the purity and medicinal qualities of the river water.

So Vishwambhar Nath Mishra – mahant (religious leader) of the Sankat Mochan temple to Hanuman the monkey god, president of a foundation set up by his father to protect the Ganges and professor of electronics engineering – knows a thing or two about activated sludge plants and faecal coliform bacteria.

The Ganges at Varanasi

Varanasi, he tells me at the temple after a night-time ceremony of chanted prayers, produces 350m litres a day of sewage, but is able to treat only 100m litres – and even that only partially. But amid the clamour of India’s general election Prof Mishra senses an opportunity to rescue the river from industrial pollution and human waste: Varanasi, also known as Benares, Banaras or Kashi (“the city of light”), has now become the focus of national politics.

“The place where you’re sitting” – he points at the mat on the floor – “Modi was sitting there on the 20th of December.” That was the day Narendra Modi of the Hindu nationalist Bharatiya Janata party, favourite to become India’s next prime minister, went on to address his first mass rally in the city.

“He was a mute spectator. Whatever I was saying, he was just listening,” says Prof Mishra firmly. “I said, ‘Modi-ji, you are going to address a big crowd. It would be nice if you could consider, if you could deliberate on this [Ganges] issue. Most people are not aware of it.’”

On that day and since, Mr Modi has responded handsomely to Prof Mishra’s request, calling the Ganges his mother and promising a clean-up. Seeking Hindu support across India, and eager for votes from the vast population of the city’s hinterland in Uttar Pradesh, Mr Modi is also standing as a member of parliament for Varanasi. Arvind Kejriwal, leader of the anti-corruption Aam Aadmi or Common People party, is doing the same to challenge Mr Modi.

As thousands of rowdy supporters packed Varanasi’s streets last week to glimpse Mr Modi presenting his nomination papers for parliament, the BJP leader praised the cultural glories of Varanasi while lamenting the state of the Ganges. In parts of Uttar Pradesh, he said in his blog, the river’s condition was “pitiable”.

For foreigners and Indians alike, the shocking state of the Ganges along much of its 2,500km between the Himalayas and the Bay of Bengal is an enduring mystery. If the river is so holy, how come the 450m people who depend on it for water and food treat it with such contempt? Why has so much state money for cleaning the river been wasted, stolen or simply never spent?

Varanasi itself provides a clue. Say it softly while you are there, but the holiest city in India is also among the filthiest and most dilapidated. Drains are blocked with garbage. Tour guides blithely discard plastic cups into the Ganges after finishing their tea. When you stumble across yet another heap of rubble in the streets, it is hard to tell if it comes from an ancient building that has collapsed or is destined for another that may – eventually – be built.

This is more than just a lack of civic pride. The river’s sanctity may itself be part of the problem. B D Tripathi, head of environmental science at Banaras Hindu University, has been concerned about the Ganges since 1972, when he bathed with his mother and encountered the floating corpse of a cow. When he spoke of pollution and started measuring it, his mother and others were appalled. “Varanasi is a religious place,” says Prof Tripathi. “They said: ‘You are not a Hindu. The water of Ganga [the Ganges] is the most pure.’”

He is not discouraged. He campaigns against dams that reduce the river’s water flow and claims to be the first to calculate how many human corpses are burnt each year at Varanasi’s main cremation ghats: 32,000, he says, releasing 200 tonnes of half-burnt flesh into the Ganges.

If Mr Modi does become prime minister, and if he is elected in Varanasi, those in the city who care for the Ganges will be quick to hold him to his promises after decades of broken government pledges. Prof Mishra says he will be “the first person to tell him: ‘You made this commitment in Sankat Mochan temple.’ Our objective is that not even a drop of sewage should go into the Ganges.” The devoutly Hindu Mr Modi has been warned.

Source:  Financial Times,

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The Ocean’s Biggest Challenge

by John Christopher Fine

Editor’s Note:  The following is excerpted from a longer piece.  It is an excellent overview of the process by which choral reefs are being destroyed.–Hardly Waite.

Nitrogen is a nutrient for algae. Nitrogen, in all of its forms, comes from various sources prevalent in human habitation and activity in Florida. The first is sewage waste. This includes direct dumping of sewage effluent into the ocean as well as treated sewage. While court rulings have ordered municipal sewage treatment facilities to close their ocean pipes, this has not happened.

Removal of nitrogen from sewage effluent is a very costly process. Few municipal budgets can afford the changeover. Many claim that the requirement to divert sewage effluent underground in deep-well injection is already a financial burden. When heavy rains occur sewage treatment facilities bypass deep-well injection and continue to pump sewage into the ocean through their “closed” pipes that run a mile underwater out to the reefs.

All water that comes to earth from rain and run-off from all manner of human activities eventually finds its way into storm drains. In Florida, where the land is flat and is composed of sand with a limestone base and geology, run off creates major pollution problems. Recently, signs have been posted on storm sewers that read “No dumping. Drains into Lake Worth.” Or into whatever waterway is convenient to get rid of the water.

Evaporation also brings high nitrogen loaded rain back to earth. Elements that evaporate do not disappear into outer space and remain gone forever as some would hope. Evaporated liquids are retained in clouds until rainfall occurs. Florida is a major cattle and animal feedlot. Animal waste evaporates. Some is drained and efforts are made to treat it. Evaporation causes it to remain in clouds then return to earth in rain.

Everything else that is put on Florida’s lawns and golf courses likewise washes off and ends up in storm drains with tropical rains. Signs that proclaim danger to humans and animals and warn not to walk on sprayed lawns make the danger obvious. Compound that posted danger by the fact that all of it, in one way or another, ends up in the environment. Run off goes into storm drains, then into the Intracoastal Waterway. At tide change it is carried out into the ocean. Consider that in Florida all lawns consist of two inches of sod grass with imported top soil placed atop sand and limestone substrate. Anything that soaks down goes into the water table somewhere.

In Florida the sugar industry has been blamed for creating vast wastelands of ocean and estuarine areas. The culprit has been nitrogen rich fertilizers and sprays used to make sugar cane grow. Sugar growers have been cooperating with government but the impact on Florida Bay and other critical marine areas have been evident by coral death and underwater wastelands. Algae is the culprit. Inland run offs of pesticides and herbicides used in many forms of agriculture including citrus, have created harm to the environment in many ways.

Water managers control a vast system of canals across Florida. In the coastal region the waters of Lake Okechobee are controlled by the U.S. Corps of Engineers and the South Florida Water Management District.

Lake Okeechobee is dammed to retain water. With the influx of people into Florida and widespread development in western areas that were once everglades and swamps, water managers have been given the task of preventing flooding that would devastate homes and shopping centers. These areas were developed after swamps and wetlands were drained. They stay dry only because water is retained in the lake and controlled by canals.

When it rains too much, water managers open canal gates and the water pours into the Intracoastal Waterway thence into the Atlantic Ocean. Canal water contains the nitrogen burden of agriculture, human and animal waste that directly affects algae growth.

Nitrogen rich waste is food for algae. The marine plants thrive and grow in such abundance that they choke other forms of life. Gorgonian soft corals, like sea fans and many other varieties of soft corals, have been killed along with other species. The result is that divers remark that once magnificent and pristine South Florida reefs look dead.

The preventative solution could have been taken many years ago. It is not that officials didn’t know that harm would be caused to the marine environment by dumping sewage and agricultural waste into the ocean. Government, with greedy developers, decided on their juggernaught without adequate planning to handle the amount of waste that would be produced by all of these people and their ancillary activities.

A byproduct of development is that people require water. Florida has been in drought for many years. While water managers throw fresh water away to respond to a need to prevent flooding over-developed swamp and everglade areas, they have not provided adequate storage of potable water for increased population.

“The reef here comes up twenty feet off the bottom. Look under the coral ledges. You’ll see sea turtles resting under there and all kinds of marine life. Delray Ledge is one of the most beautiful reefs in the world,” Captain Craig Smart told his divers. Unfortunately algae is killing coral on this and other reefs.

A second dive was made just south of the Boynton Beach Inlet. The reef, like others in the chain, is about a mile offshore. Inlet dredging, with an automatic boom to keep the channel clear, throws out murky muck in the county’s Inlet Park Beach south of the jetty. It is not a pleasant sight for bathers and beach goers but the channel will sand up if it is not dredged. This drainage ditch, from Intrtacoastal to the Atlantic, was never designed as a passage out into the ocean for boats. The inlet, as yellow warning signs proclaim, is drainage for the Intracoastal Waterway. Without drainage at tide change the Intracoastal would be a noisome, polluted sewer.

The reefs near the Boynton Inlet have been hard hit with algae. Coral is dead. Marine life has decreased food supply. Marine turtles return to this area every winter to mate then lay eggs on Florida’s beaches to continue the chain of life that has been going on for eons. Sponges and other food turtles eat are covered with algae. The chain of life is being adversely affected.

Eventually all waste water will have to be processed in ways in which nitrogen and other damaging elements are removed before it is dumped into the ocean. It is a costly process to implement. Meanwhile the 900 million or so gallons of sewage produced every day in Palm Beach County has to go somewhere.

It was only one diver that voiced concern after surfacing. Had a ship containing oil broken apart, had an oil rig cracked causing oil to wash up on shore, the outcry would have come from many voices. The quiet menace of algae pollution is unseen save by a few divers and unreported except through dedicated environmental organizations. Their message goes unheeded as uncritical. If life in South Florida is to be enjoyed by future generations then systems must be put in place to preserve this last frontier, the only reef structure in the Continental U.S.

Source: Epoch Times

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I was struck by a statistic I read in a research report the other day. There’s a commodity that we use every day without thinking about it. We rarely consider it as an investment either.

And yet, a basket of stocks related to this commodity has outperformed gold, oil and gas, and global stocks over the past ten years.

What is this miraculous substance?

Water.

Have we hit ‘peak water’?

We’ve covered water as an investment theme in MoneyWeek magazine on several occasions in the past. It may seem an odd choice – after all, water is not a globally traded commodity, like oil.

But in fact, it makes a lot of sense. There is always good profit potential in any area where there is an imbalance between supply and demand. You can make usually make good money from the companies working to correct that imbalance.

And with water, these two forces are more acute than in perhaps any other substance.

Demand is high and rising. Water is necessary for life. There’s no substitute. As the global population grows, and we all (hopefully) become wealthier, there will be more and more demand for it.

Meanwhile, supply is limited. Fresh water – water we can use – accounts for just 2.5% of all water in the world. And a big chunk of that is locked up in ice. So there’s actually not that much water to go around. The other problem is that the water often isn’t where it needs to be – ie where the people are. It’s surprisingly hard stuff to transport.

Bank of America Merrill Lynch reckons we may even have reached ‘peak water’. Now, ‘peak’ has become something of an investment world cliché. But you take their point. There’s a lot of stress on the water supply.

The UN reckons that around a fifth of the world’s population lives in areas where there is a physical shortage of water. Another quarter faces “economic water shortage”. This is where water is physically present, but the infrastructure isn’t there to get it from the source to the people who need it.

And this situation is only going to get worse. Between water pollution and depletion of underground aquifers, and the risks of extreme weather events becoming more frequent, the danger is that even as demand grows, supply is going to become more scarce.

In short, water poses a problem. And you can make money from the companies involved in solving this problem.

Source: MoneyWeek

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