Bacteria
Coliform Bacteria are not disease producing organisms themselves, but are used as an indicator of disease producing organisms. When coliform bacteria are present, this is an indication that the water source may have been contaminated by surface water, septic system effluent, unsanitary water treatment equipment and may contain disease producing organisms. Chlorination is the best method for eliminating bacteria from the water supply.

Color
Color may be caused by dissolved organic material from decaying vegetation and/or certain inorganic material such as iron or manganese. While color is not objectionable from a health standpoint, its presence is aesthetically objectionable and suggests that the water needs appropriate treatment.

Odor
Odor in water can be caused by organic compounds, inorganic salts or dissolved gases. These materials may come from domestic, agricultural or natural sources. Water should be free of any objectionable odor.

"Dirt"
Turbidity is the presence of suspended material such as clay, silt, organic, inorganic and biological materials. Turbidities in excess of 5 units are detectable in a glass of water and are usually objectionable for aesthetic reasons. The most common method of removing turbidity is with a filter system.

Acid
pH is a measure of the acid or alkaline content of water. Water with a low pH (acidic) is corrosive to plumbing and may cause leaching of toxic metals such as lead or copper into the water supply. An acid neutralizer can be used to effectively raise the pH to reduce corrosion.

Nitrates
Nitrate Nitrogen can be caused by natural decomposition of organic matter, agricultural fertilizers, or waste disposal. High levels of nitrates can indicate a potential health risk of methemoglobinemia (blue baby syndrome), especially to infants. Reverse osmosis or ion exchange resins can remove nitrates.

Sulfates
Sulfates appear in natural waters. Elevated levels may cause an unpleasant medicinal taste, gastrointestinal distress and may impart a "rotten egg" odor.

Chlorides
Chlorides are found in all water supplies. When sodium is also present (from road salt run-off or water softener backwash), water may have a salty taste. High concentrations of chlorides may corrode pipes.

Salt
Sodium levels of water may be a health risk to those persons with hypertension, heart, kidney or liver disease. The usual low sodium diet allows 28mg/L in the drinking water. Elevated sodium levels are likely to be seen from water softeners, road salt run-off or sewage contamination.

Iron
Iron levels above 0.3 mg/L can discolor fixtures and laundry and may impart a metallic taste to the water. Iron is frequently found in water because of the large amounts present in the soil. Common methods for removing iron from water are aeration or chlorination of the water followed by filtration.

Manganese
Manganese at levels greater than 0.05 mg/L may produce a brownish black stain in laundry and dishwashers and can impart an objectionable odor and taste. It is usually found with iron in soil with a high mineral content. Oxidation or water softeners are common methods of manganese removal.

Copper
Copper in small amounts is not considered detrimental to health. Elevated copper levels will impart a bitter undesirable taste and can cause gastrointestinal distress. When water is acidic, copper can leach from piping and leave blue-green stains on fixtures.

Hard Water
Hardness is an indication of calcium and magnesium carbonate concentrations in water supplies. Hard water is not physically harmful but causes scaling in water lines, hot water heaters and appliances. It also reduces the cleaning action of soap and detergents and can leave your skin feeling dry.

Water hardness is measured in milligrams per liter (mg/l) or parts per million (ppm).

Radon
Radon in well water can contribute to the indoor air levels of radon in your home. Radon is released into the air as water pours into sinks, tubs, and appliances. Activities that use hot water, such as showering, can release large amounts of radon. If your water comes from a private well, the State of Connecticut Department of Health Services Radon Program recommends that you test the radon levels in your water. Radon should be removed before it enters the house using a granulated activated carbon (GAC) filter unit or by the use of an aeration treatment system. More about radon in your water.