Routine analysis is generally for Total Coliform Bacteria, which includes all relatives of the coliform group and serves as an indicator of contamination by waste water. Analysis of fecal coliform bacteria may be used to indicate whether the contamination is from human or animal waste. Water testing in your area may be provided through your county health dept, local hospital, Minnesota Extension Service county office, private laboratories, or water treatment companies. Testing is generally simple and inexpensive. Thus the appearance of any colonies of bacteria indicates some form of contamination.
Shallow wells are particularly susceptible to bacterial contamination.
It is, therefore, important that these wells be properly constructed, cased, and maintained and that septic systems be built to code and pumped out regularly. Water from a newly constructed well should be tested before use. Twentyfive percent of samples from new wells are coliform positive. The contamination is not from sewage, but from the introduction of coliform during drilling, pump installation, plumbing, or sampling. During times of drought or lowered water table levels, new drainage pathways may be established for groundwater seepage or recharge.