Common Water Problems
Iron
Iron in water causes an unpleasant metallic taste. With as little as 0.3 ppm of iron present in your water it can combine with the tannin in tea, coffee, and alcoholic beverages to produce an unpleasant grey-ish black appearance as well as cause red stains in toilets, plumbing fixtures, tableware and laundry. Iron can exist in water in two different forms. Recommendations depend on the form of iron present. Water containing "ferrous iron" are clear and colorless when drawn. Exposure to air converts ferrous iron into the insoluble, reddish brown "ferric iron". Iron may be removed from water by the following methods, depending upon the amount and type of iron present.
FERROUS IRON - A water softener can remove up to 4 ppm of ferrous iron depending upon size and the type of softener. Very large water softeners can remove up to 6 ppm of iron.
FERRIC IRON - If the water contains considerable ferric iron as evidenced by a reddish brown color, use a sediment filter ahead of the water softener. The sediment filter will remove a portion of the insoluble ferric iron and the water softener the soluble ferrous iron.
Chlorination and Filtration - This means of iron removal is recommended only when sulfur, extreme iron bacteria, or taste and odor problem also exists. An chlorinator should be added to facilitate iron removal. Use an carbon filtration system following the chlorinator to remove the iron particles as well as any excess chlorine.
NOTE - The success of this method of Iron Removal is dependent upon at least 20 minutes of contact time for the Chlorine to fully react with the Iron. This contact time can be achieved by a Large Contact Tank. Chlorine causes Iron in your Water to form Particles which can then be Filtered.
Iron and Acidic corrosion - Water with a pH below 7 (acidic water) will usually cause iron-pick up in piping systems and contribute to iron staining problems. Blue to green staining will result if the piping is copper. The lower the pH, the greater the corrosive tendency of the water. The recommended pH limits of water for use in the home are 7.0 to 10.6. Waters with pH less than 6.8 contain sufficient acidity to cause significant corrosion and should always be treated. Waters containing appreciable amounts of oxygen also tend to be corrosive.
Neutralization of Acid Waters - Acid neutralizing filters contain a mineral that reacts with acidity to raise the pH of water. This process slowly dissolves the mineral and adds a few grains of hardness to the water. Because of the increased hardness and the iron content, a softener is recommended after the mineral is added. The combination of an acid neutralizer filter and softener can be applied to acidic waters containing up to 6 ppm of iron. Acid neutralizing filters require frequent backwashing and the addition of several pounds of mineral once a year.
NOTE - On low pH water a pH Neutralizer should be add prior to beginning any recommendation
Iron Bacteria
Bacterial or "live" iron is probably the most misdiagnosed of all iron applications. Unlike ferrous or ferric iron that can be diagnosed by the color of the water, bacterial iron is not readily apparent. It may appear as feathery or lumpy sediment if visible at all and if not properly treated will grow inside most water filtration systems fouling the media and causing staining. Generally, only chlorination or a redux media is effective with this type of iron. Other types of pre-oxidation can increase the problem or clog the plumbing or filter.
Sulfur
Hydrogen Sulfide (H2S) is a gas which gives a "rotten egg" Sulfide odor to water supplies. Water contaminated with Sulfides are distasteful for drinking purposes and useless for processes in practically all industries. Most sulfur waters contain from 1 to 5 ppm of hydrogen sulfide. Hydrogen sulfide can interfere with readings obtained from water samples. It turns hardness and pH tests gray, and makes iron tests inaccurate. Chlorine bleach should be added to eliminate the H2S odor; then the hardness, pH and iron tests can be done. Hydrogen sulfide can not be tested in a lab, it must be done in the field. Hydrogen sulfide is corrosive to plumbing fixtures even at low concentrations. H2S fumes will blacken or darken painted surfaces, giving them a "smoked" appearance and they will also corrode the coil of your HVAC.
Hardness
Hardness is due to calcium and magnesium dissolved in water and is measured in grains or ppm. Iron can also contribute to hardness. These elements form scale in piping, water heaters, and dishwashers causing expensive repairs. Hard water increases soap consumption, starches your laundry, leave a scratchy feeling after bathing, leaves hair hard to manage, scales glasses and dishes, and affects taste and tenderness of many cooked foods.
Hardness is removed with a water conditioner (or water softener). The proper size and type of softener depends upon:
- The compensated hardness (iron content determined)
- The amount of water used per day (outside faucets excluded)
- Flow rate required
While this is a matter of opinion to many consumers, usually a water softener should be installed over 5 grains of hardness. By most accounts, anything 5 grains and over is considered hard water and will scale. It is important to understand that the word "hardness" is not a technical term, merely a term of descriptive convenience, hence the difficulty sometimes in determining what exactly is hard water.
Hardness in water is the most common water quality problem reported by U.S. consumers. In fact, hard water is found in more than 85 percent of the United States. Hard water occurs when excess minerals in the water create certain nuisance problems. While these water problems can be frustrating, water hardness is not a safety issue. Hard water is safe for drinking, cooking, and other household uses.
Hard water can cause several problems for consumers including decreased life of household plumbing and water-using appliances, increased difficulty in cleaning and laundering tasks, decreased efficiency of water heaters, and white/chalky deposits on items such as plumbing, tubs, sinks, and pots and pans.
Causes of Hard Water:
Approximately 22 percent of the earth's fresh water is ground water, and naturally, as it flows through soil and rock, it picks up minerals. Hard water results when an excessive amount of calcium and magnesium are present. Total hardness is measured in grains per gallon of water (gpg) or milligrams per liter (mg/l). Grains per gallon (gpg) is a unit of weight for a volume of water, as is milligrams per liter (mg/l). Sometimes hardness is measured in parts per million (ppm). Parts per million (ppm) measures the unit(s) of a substance for every one million units of water. Milligrams per liter (mg/l) and parts per million (ppm) are roughly equal in water analysis. One gpg (1gpg) is equivalent to 17.1 ppm or mg/l. When conducting chemical analysis, laboratories usually measure hardness minerals in either grains per gallon (gpg) or milligrams per liter (mg/l). You can evaluate the hardness of your water supply by referring to the chart above.
Tannins
Tannins are water soluble, organic phenolic compounds formed by the decomposition of vegetation. Tannins are found in water in almost any location where large quantities of vegetation have decayed. Tannins cannot simply be filtered out of water as they consist of microscopic, unsettleable, colloidal particles that carry a negative charge. Due to the materials that have decayed, tannins create a yellowish color in water. Though this may not be visible in a glass of water, a tubful of water or water placed in a Styrofoam cup will appear slightly yellow. Tannins in water above a pH of 6 must be removed by an ion exchange; Tannins below a pH of 5 must be corrected with a pH Nuetralizer
Taste & Odor
Taste problems in water come from total dissolved solids (TDS) and the presence of such metals as iron, copper, manganese, or zinc. Magnesium chloride and magnesium bicarbonate are significant in terms of taste. Fluoride may also cause a distinct taste. Taste and odor problems of many different types can be encountered in drinking water. Troublesome compounds may result from biological growth or industrial activities. The tastes and odors may be produced in the water supply, in the water recommendation plant from reactions with recommendation chemicals, in the distribution system, and /or in the plumbing of consumers. Tastes and odors can be caused by mineral contaminants in the water, such as the "salty" taste of water when chlorides are 500 mg/l or above, or the "rotten egg" odor caused by hydrogen sulfide. Odor in the drinking water is usually caused by blue-green algae. Moderate concentrations of algae in the water can cause it to have a "grassy", "musty" or "spicy" odor. Large quantities can cause the water to have a"rotten", "septic", "fishy" or "medicinal" odor. Decaying vegetation is probably the most common cause for taste and odor in surface water supplies. In treated water supplies chlorine can react with organics and cause odor problems.
Taste and odor can be removed by oxidation-reduction or by activated carbon adsorption. Aeration can be utilized if the contaminant is in the form of a gas, such as H2S (hydrogen sulfide). Chlorine is the most common oxidant used in water recommendation, but is only partially effective on taste and odor. Potassium permanganate and oxygen are also only partially effective. Chloramines are not at all effective for the recommendation of taste and odor. The most effective oxidizers for treating taste and odor, are chlorine dioxide and ozone. Activated carbon has an excellent history of success in treating taste and odor problems. The life of the carbon depends on the presence of organics competing for sites and the concentration of the taste and odor causing compound.
Lead
Lead, a metal found in natural deposits, was not known to be poisonous and was commonly used in household plumbing materials and water service lines. Today it is known that lead in drinking water can cause a variety of adverse health effects and should be a priority to eliminate. In babies and children, exposure to lead in drinking water above the action level can result in delays in physical and mental development, along with slight deficits in attention span and learning abilities. In adults, it can cause increases in blood pressure. Adults who drink this water over many years could develop kidney problems or high blood pressure.
Lead is rarely found in source water, but enters tap water through corrosion of plumbing materials. Homes built before 1986 are more likely to have lead pipes, fixtures and solder. The most common problem is with brass or chrome-plated brass faucets and fixtures which can leach significant amounts of lead into the water, especially hot water.
MTBE
What is MTBE? (Methyl Tertiary-Butyl Ether)
The gasoline additive MTBE has contaminated thousands of drinking water supplies around the country. The chemical is released into the environment via leaking storage tanks and spills, including small gas spills that routinely occur when filling up your car at the service station.
About MTBE
MTBE stands for the synthetic compound Methyl Tertiary-Butyl Ether and is a gasoline additive that has contaminated drinking water across the country. Made from methanol and a by-product of the oil refining process, it was added to gasoline in an attempt to make gas burn cleaner, but studies show it has had little effect on curbing air pollution.
On July 27, 1999 an EPA panel recommended that MTBE be reduced in use as a gasoline additive because of the toxic hazards that MTBE poses to drinking water supplies throughout the country. MTBE is a known animal carcinogen and possible human carcinogen. The reported U.S. production of MTBE in 1992 exceeded nine billion pounds - virtually all of it is added to gasoline. Oil companies reportedly make approximately $3 billion per year from MTBE.
Why does MTBE contaminate our water?
MTBE, like other ethers, is hydrophilic; in other words, it has a chemical attraction to water molecules. It is more than thirty times more soluble in water than other toxic compounds of gasoline. MTBE does not readily bind to soil particles and resists natural degradation. It is these qualities that cause MTBE to travel easily and quickly into underground water supplies. When MTBE is released into the environment via transport accidents, leaking tanks, or simple over-filling at gas stations, MTBE travels great distances underground to the water table. MTBE can contaminate surface waters, but underground drinking water supplies are most at risk. In 1999, the U.S. Geologic Survey reported detecting MTBE in 21% of groundwater samples taken away from all known gasoline leaks and spills where MTBE is used.
Where did it come from?
In the late 1970s, gasoline companies started using MTBE in gasoline to replace lead and to boost octane. In 1990, in response to concerns over air pollution and aggressive industry lobbying, Congress amended the Clean Air Act to require the use of fuels which add oxygen to gasoline. Called reformulated gas or "RFG," this oxygenated gasoline is now required in all or parts of 17 states. MTBE is the best known oxygenate, and the one embraced by most oil companies although other oxygenates are used in some areas.
What are the concerns?
MTBE is difficult to clean up MTBE as it easily reaches and contaminates groundwater because it is water-soluble and degrades very slowly. It spreads quickly and persists indefinitely in groundwater. For example, a simple car accident could contaminate an entire underground aquifer. This water solubility makes it difficult and costly to clean up. Plumes of MTBE releases into groundwater have already been shown to persist for decades. The remediation of MTBE contamination requires a much higher ration of removal medium (for example, activated carbon) per unit of the contaminant than does gasoline without MTBE.
MTBE may cause health risks
As the EPA recognizes, there is still much uncertainty about the extent of the health risk associated with chronic, low-level exposure to MTBE in drinking water. MTBE is a known animal carcinogen. The U.S. Environmental Protection Agency classifies it as a possible human carcinogen. At concentrations at or below five (5) parts per billions ("ppb"), MTBE gives otherwise pure water a foul turpentine-like taste and odor, rendering it unfit for consumption. The distressing taste and odor can be detected in water in concentrations at or below 5 parts per billion, although sensitivity to the odor and distaste varies greatly among individuals.
pH
Acidic and Iron corrosion - Waters with a pH below 7 (acid waters) usually will cause iron-pick up in piping systems and contribute to iron staining problems. Blue to green staining will result if the piping is copper. The lower the pH, the greater the corrosive tendency of the water. The recommended pH limits of water for use in the home are 7.0 to 10.6. Waters with pH less than 6.8 contain sufficient acidity to cause significant corrosion and should always be treated. Waters containing appreciable amounts of oxygen also tend to be corrosive.
Neutralization of Acid Waters - Acid neutralizing filters contain a mineral that reacts with acidity to raise the pH of water. This process slowly dissolves the mineral and adds a few grains of hardness to the water. Because of the increased hardness and the iron content, a softener is recommended after the mineral is added. The combination of an acid neutralizer filter and softener can be applied to acidic waters containing up to 6 ppm of iron. Acid neutralizing filters require frequent backwashing and the addition of several pounds of mineral once a year.
Chlorine
Chlorine taste and odor in the water is usually caused by Chlorine's deliberate introduction into municipal water supplies for the destruction of bacteria and volatile organics. Chlorine can exist in water in its free state (Called free chlorine) or can make chlorine compounds. Both are equally objectionable.
The most cost effective method to remove chlorine from the water is through a backwashable granular activated carbon filter. This non-maintenance solution eliminates the need to continually change cartridge filters and the media lasts much longer than the cartridge counterparts.