Water Quality Terms

COLIFORM BACTERIA
Bacteriological safety of water supplies is based on analyses for Coliform Bacteria. These bacteria are present in large numbers in the soil and in the digestive tracts of humans and animals. They do not usually cause disease but their presence in water is an indication of contamination from surface water or septic waste. Any waste material contaminating your water is unnatural, and suggests that pathogenic (disease causing) organisms may also be present. Such water is judged as "UNSAFE" for human consumption. Bacteriologically "SAFE" means there is an absence of Coliform bacteria.

NITRATES
10 mg/l NO 3 -N (ten milligrams per liter (parts per million) nitrate and nitrate nitrogen) is the maximum standard for drinking water in this county. A nitrate level above 10 mg/l in drinking water may cause serious health effects in infants and may indicate the presence of farm chemicals - even pesticides, in your water. A disease called methemoglobinemia (Blue Baby Syndrome) can be caused by nitrates in infants less than 6 months of age. Nitrates in water are generally unnatural, but background levels of 1 mg/l or less are not unusual. Elevated levels should be monitored frequently.

FLUORIDE
Fluoride as it occurs naturally in water supplies or in public drinking water, has been shown to be effective in reducing dental cavities. A level of 1.0 mg/l is desirable, but a level above 2.4 mg/l is likely to cause staining of teeth. Children regularly drinking water with close to or greater than 1.0 mg/l of fluoride should not receive fluoride supplements, and the family dentist should be informed of the fluoride level in the water.

ARSENIC
Arsenic is a toxic element, and is widespread in the environment due to its natural occurrence and former extensive use in herbicides and pesticides. The most common, natural occurrence of arsenic is our diets; arsenic is found in many foods. Horizontal white lines on the toenails and fingernails indicate chronic arsenic poisoning. Other symptoms may include numbness and tingling in arms and legs, weight loss, nausea and diarrhea alternating with constipation, and loss of hair. Arsenic poisoning can make people tired, lethargic and depressed without showing other long-term symptoms. Levels above 50 parts per billion in drinking water are considered harmful by the EPA and DNR.

IRON AND/OR SULFUR BACTERIA
Because iron is one of the most abundant minerals in the earth's crust, it is very common in groundwater. Most are probably familiar with what happens when there is too much iron in water - a reddish-brown color, stained laundry, and poor tasting coffee. An equally common but less understood problem is infestation of water supplies with iron bacteria. These microorganisms combine mineral iron or manganese in the water with oxygen and use it to form rust-colored deposits. In the process, the bacteria produce a brown slime that builds up on well screens, pipes, and plumbing fixtures. A "rotten egg" smell is often caused by the presence of sulfur bacteria that produce hydrogen sulfide gas. Hydrogen sulfide gas is highly corrosive and can eat away plumbing connections and metal piping, including your well casing. Iron and sulfur bacteria are not harmful but can clog pipes and plumbing fixtures, produce odors, and provide a habitat for other bacteria to live including coliform bacteria.

Please call our office or lab if you have any questions.