DIY Water Purification
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If you want clean drinking water these days you are better off to do it yourself. With BPA in plastic bottles and the litany of poisons and organic contaminants in tap water, you can't be sure how safe your water is, unless you purify it yourself.
Even municipal water supplies, that are treated and considered safe by the EPA, at the very least contain chlorine, fluoride, heavy metals, pharmaceuticals, industrial pollution and volatile organic compounds or VOC's. In addition, groundwater wells will contain some of these as well as protozoan organisms that can cause illness and sediment that should be removed to keep plumbing and fixtures clean and working properly. Fortunately there are several options for removing just about any contaminant that may be in your water, right at the tap.
Basic Water Filtering
The first step to effective water purification is the removal of sediment. Dirt, sand, silt, scale, rust and other large particles are removed through the use of a pleated, mesh filter. Removing these larger particles will enable all the following stages in a multi–stage system to work better.
The next step of basic water filtering is the removal of chlorine, microorganisms and VOC's. These exist in varying degrees in most water sources. A carbon filter is used to remove these common contaminants. Carbon filters are available as activated charcoal or solid carbon block filters. Carbon filters are found in all water filtering systems and are usually the only filter in a faucet or pitcher filter.
After water passes through the basic process of sediment removal and the filtering of common contaminants, it can pass on to final use or it may be filtered further to remove the smaller and more dangerous contaminants from water and make it safer to drink.
Filtering Specific Contaminants
If you have industrial chemicals, pharmaceuticals, heavy metals and other poisons in your water, these will require special treatment to be removed. In some cases, a filter made specifically to remove a particular contaminant can be add as a third or fourth stage in the basic filtering process. These would include filters for iron, lead and copper or an ultra violet (UV) light filter to kill microorganisms in groundwater.
A reverse osmosis water filtering system will remove more contaminants from water than any other home–based system. Reverse osmosis is the process of forcing water through a semi–permeable membrane to remove particles down to 0.00005 microns, according to some manufacturers. This can account for many of the hazardous substances that are found in normal water sources.
Faucet and Pitcher Water Filters
Faucet and pitcher water filters are limited in their ability to clean your water. The carbon filter, that is the whole system, can only remove chlorine and some VOC's, in most cases. Faucet filters tend to become saturated with contaminants quickly requiring frequent replacement. This can be costly and inconvenient and you will still be drinking water that contains some contaminants. In addition, the water flow from one of these filters is painfully slow and leaks are always a possibility.
If your goal is to remove the basic contaminants from your drinking water at a low start–up cost (about $17 for some brands), a screw–on faucet filter will do an adequate job of removing chlorine taste and some VOCs. In addition, depending on the brand you choose, a faucet filter may also reduce some heavy metals and even some pharmaceuticals, but not all of these will be eliminated.
Reverse Osmosis Filtration
Reverse osmosis (RO) is a better choice for more effective purification of drinking water and will be more economical over the long run. While the start–up cost may be high, about $300 for a basic 5–stage system, the cost of operating the system is only pennies for about 45 gallons of clean drinking water a day. The system consists of 4 filters and a storage tank and will usually fit under the kitchen sink.
Originally investigated by the University of California at Los Angeles and used by the U.S. Navy to desalinate sea water for drinking, RO is currently used in over 15,000 desalination plants throughout the world and by many bottled water companies to produce their product.
While RO does remove the widest array of contaminants of any home water filtering system it doesn't remove everything and the membrane is vulnerable to chlorine degradatation. Therefore a carbon filter is essential in this system. A good reverse osmosis water filtering system will contain a polypropylene–mesh sediment filter, two carbon filters, the semi–permeable membrane, a storage tank and a dispenser.
Whole House Water Filters
Most people would benefit from a whole house water filter to remove the most common water contaminants before they reach the drinking water filters. This will allow the drinking water system to be more effective and reduce the need to replace filters so frequently.
A whole house water filter system is installed at the point where the water supply pipe enters the house and will clean all the water you use. This will eliminate chlorine in showers where it can be absorbed through the skin and in the laundry where it can dull fabric colors.
The typical flow rate is around 50 gpm and the filters can clean about 100,000 gallons of water before they need cleaning or replacement. The cost for a two stage system containing a sediment and carbon filter is around $200 for the basic components including housings and filters.
