Many people are exhibiting a growing concern as to the quality of their drinking water now and in the future. Individuals were under the sometimes false assumption, that if their water looked and tasted good, that it was “safe to drink”. Following is a brief discussion which may be of interest to you as a home owner on a private well water supply.

Water purity or bacteriological suitability is determined by testing for coliform bacteria and a heterotrophic plate count. E. Coli are found in large numbers as normal inhabitants of the intestinal tract of mammals. Their presence in water is indicative of fecal contamination. Some serotypes of coliform can cause intestinal disease, particularly in young children or otherwise weakened individuals. Symptoms may include nausea, vomiting, cramping and or dysentery.

Other pathogens, or disease producing organisms, such as Salmonella and Campylobacter, enter the water supply via the same method of contamination as E. coli. Laboratories do not routinely test for these pathogens due to the fact that they are very difficult to isolate and identify, are found in relatively small numbers, enter the water supply sporadically, and do not survive long in water. Hence, they are likely to be missed by routine laboratory screening procedures. E. Coli is and indicator organism, which is much easier and cost effective to identify, and found in large numbers where fecal contamination is evident. Good quality drinking water should contain <1 of coliform, or non-detected, per 100 milliliters of water.

A heterotrophic plate count may be done which would indicate the general bacteria composition of water and the presence of non-fecal organisms. Good quality water should contain < 100 per milliliter of water.

Color, odor, and turbidity are physical characteristics which may be used as indicators that there may be a problem and further testing may be necessary. However, keep in mind that the absence of any noticeable color, odor, or turbidity, does not ensure that your water supply is bacteriologically safe to drink.

pH indicates the acidity or alkalinity of water. Generally, a pH of 6.5 – 8.5 is desirable. Excessive variation in either direction may contribute to corrosion.