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Note: This information has been taken principally from a paper titled "Sensitivity: A Key Water Conditioning Skill" by Wes McGowan. The paper was published in Water Technology, September/October 1982. The following chart is intended to serve as a general guide for consumers in determining the cause of problems with their water that can be felt, smelled, tasted, or seen. In some cases, these symptoms may indicate a serious problem -- in others, only the taste and smell of tap water (its aesthetics) may be affected, not its safety. If the symptoms indicate a potential health problem, test the water to determine what contaminants are present. |
| Impurity or Contaminant | Symptom | Cause | Health Effects | Means of Treatment |
| Hard Water | Soap curd, and scum in wash basins & bathtub. Whitish scale deposits in pipes, water heater & tea kettle. | Calcium (limestone) and magnesium salts. | Aesthetic only | Cation exchange water softener. |
| Grittiness | Abrasive texture to water when washing or residual left in sink. | Excessively fine sand, silt in water. | Various -- sand could trap contaminants | Sand trap in ultra-filtration. |
| Impurity or Contaminant | Symptom | Cause | Health Effects | Means of Treatment |
| Odor | Musty, earthy or wood smell. | Generally, harmless organic matter. | Aesthetic only | Activated carbon filter. |
| Chlorine smell. | Excessive chlorination. | Could occur from formation of disinfection byproducts | Dechlorinate with activated carbon filter. | |
| Rotten egg odor - tarnished silverware. | 1. Dissolved hydrogen sulfide gas. 2. Presence of sulfate reducing bacteria in raw water. |
Various effects | 1. Manganese greensand filter - constant chlorination followed by filtration/
dechlorination.
2. Constant chlorination followed by activated carbon filter. |
|
| Hot water, rotten egg odor. | Action of magnesium rod in hot water heater. | Various Effects | Remove magnesium rod from heater. | |
| Detergent odor, water foams when drawn. | Seepage of septic discharge into underground water supply. | Disease-causing microorganisms may be present | 1. Locate and eliminate source of seepage - then heavily chlorinate
well.
2. Activated carbon filter will adsorb limited amount. |
|
| Gasoline or oil (hydro-carbon) smell. | Leak in fuel oil tank or gasoline tank seeping into water supply. | Fuel components may be toxic or carcinogenic | No residential treatment. Locate and eliminate seepage. | |
| Methane gas. | Naturally occurring caused by decaying organics. | Various effects | Aeration system and repump. | |
| Phenol smell (chemical odor). | Industrial waste seeping into surface or ground water supplies. | Various -- compounds may be carcinogenic | Activated carbon filter will adsorb short-term. |
| Impurity or Contaminant | Symptom | Cause | Health Effects | Means of Treatment |
| Taste | Salty or brackish. | High sodium content. | Aesthetic only | 1. Deionize drinking water only with disposable mixed bed - anion/cation
resins; or
2. Reverse osmosis; or 3. Home distillation system. |
| Alkali taste. | High dissolved mineral containing alkalinity. (Stained aluminum cookware.) | Aesthetic only | Reduce by reverse osmosis. | |
| Metallic taste. | 1. Very low pH water (3.0-5.5).
2. Heavy iron concentration in water above 3.0 ppm Fe. 3. Leaching of lead and copper |
Various -- depends on cause | 1. Correct with calcite type filter (see Acid Water).
2. (See Iron Water). |
| Impurity or Contaminant | Symptom | Cause | Health Effects | Means of Treatment |
| Turbidity | Dirt, salt, clay. | Suspended matter in surface water pond, stream or lake. | Turbid water may contain disease causing microorganisms | "Calcite" or Neutralize (media) type filter - up to 50 ppm |
| Sand grit, silt or clay substances. | Well sand from new well or defective well screen. | Turbid water may contain disease causing microorganisms | Sand trap and/or new well screen | |
| Rust in water. | Acid water causing iron "pick-up." | Turbid water may contain disease causing microorganisms | Neutralizing calcite filter to correct low pH acidity and remove precipitated iron | |
| Gray string-like fiber. | Organic mater in raw water algae, etc. | Turbid water may contain disease causing microorganisms | Constant chlorination followed by activated carbon filter to dechlorinate. | |
| Acid water | Green stains on sinks and silver, porcelain bathroom fixtures. Blue-green cast to water. | Water which has high carbon dioxide content (pH below 6.8) reacting with brass and copper pipes and fittings. | Could lead to health effects if acid water causes leaching of lead and copper | 1. Neutralizing calcite filter down to pH of 5.5, or
2. Calcite/ Magnesia - oxide mix (5 to 1) for higher flow rate and to correct very low pH water. 3. Soda ash chemical feed followed by filtration. |
| Discolored water red, "Iron" water | Brown-red stains on sinks and other porcelain bathroom fixtures. Water turns brown-red in cooking or upon heating. Clothing becomes discolored. | 1. Dissolved iron in influent (more than 0.3 ppm Fe+) water appears clear when first drawn at cold water faucet. Above 0.3 ppm Fe causes staining. | Various effects | 1. Can remove 0.5 ppm of Fe+ for every grain/gal of hardness to 10 ppm
with water softener and minimum pH of 6.7.
2. Over 10 ppm Fe+ chlorination with sufficient retention tank time for full oxidation followed by filtration/ dechlorination. 3. In warm climates residual aerator and filtration will substantially reduce iron content. |
| 2. Precipitate iron (water will not clear when drawn). | Various effects | 1. Up to 10 ppm iron removed by manganese greensand filter, if pH 6.7
or higher, or;
2. Manganese treated, non-hydrous aluminum silicate filter where pH of 6.8 or higher and oxygen is 15% of total iron content. 3. Downflow water softener with good backwash, up to 1.0 ppm Fe. Above 1 ppm to 10 ppm use calcite filter followed by downflow water softener. Calcite media type filter to remove precipitated iron. |
||
| Brownish cast does not precipitate. | Iron pick-up from old pipe with water having a pH below 6.8. Organic (bacterial) iron. | Various effects | 1. Treat well to destroy iron bacteria with solution of hydrochloric
acid then constant chlorination followed by activated carbon media filtration
and dechlorination.
2. Potassium permanganate chemical feed followed by filtration. |
|
| Reddish color in water sample after standing 24 hours. | Colloidal iron. | Various effects | Constant chlorination followed by activated carbon media filter dechlorination. | |
| Yellow water | Yellowish cast to water after softening and/or filtering. | Tannins (humic acids) in water from peaty soil and decaying vegetation. | Various effects | 1. Adsorption via special macro-porous Type I anion exchange resin regenerated
with salt (NaCl) up to 3.0 ppm.
2. Manganese greensand or manganese treated sodium alumino-silicate under proper set of conditions. |
| Milky water | Cloudiness of water when drawn. | 1. Some precipitant sludge created during heating of water.
2. High degree of air in water from poorly functioning pump. 3. Excessive coagulant-feed being carried through filter. |
1. Various effects 2. Aesthetic only 3. Various effects |
1. Blow down domestic or commercial hot water heater tank periodically.
2. Water will usually clear quickly upon standing. 3. Reduce coagulant quantity being fed, service filters properly. |
| Very high chloride content in water | Blackening and pitting of stainless steel sinks and stainless ware in commercial dishwashers | 1. Excessive salt content.
2. High temperature drying creates chloride concentration accelerating corrosion. |
Various effects | 1. Use other chloride resistant metals.
2. Reduce total dissolved solids by reverse osmosis. |
