Coliform bacteria

Total coliform bacteria are microorganisms that are commonly present in soil, sewage, surface water and very shallow groundwater. E. coli (Escherichia coli) bacteria are a subset of the total coliform group that are found in sewage.

The presence of total coliform and/or E. coli bacteria in drinking water poses a potential health hazard.  The presence of these bacteria indicates a possible sanitary defect in the well system, which could allow other harmful contaminants to enter the system.

If coliform bacteria are found in your water, do not consume the water without disinfecting first.  Boiling the water for at least 1 minute will kill the bacteria.  Your well may need to be shock chlorinated or other maintenance may be needed.

How to Shock Chlorinate Your Well

Nitrates

Nitrate is a naturally occurring compound found in the environment with high concentrations in animal waste, septic tanks and nitrogen-containing compounds such as fertilizers.

High levels of nitrate in drinking water (>10 mg/L) may pose a serious health hazard for infants. Infants who are fed formula or juice with elevated levels of nitrate could develop a life threatening illness called methemoglobinemia, or “blue baby syndrome,” which results in blue-gray coloring of the skin due to a lack of oxygen in the blood.  

New research studies suggest potential health hazards for adults following long-term consumption of elevated nitrate levels.

Elevated nitrate level = 10 mg/L or higher.

Iron, Hardness, Sulfate, and Fluoride Testing

These chemicals are considered “secondary water contaminants”.  These contaminants are NOT threatening to human health.  However, they can cause nuisance issues such as undesirable taste and odors or a cloudy or colored appearance.  In some cases, they can cause problems with water equipment such as faucets, pipes, or filtration systems and water softeners

The table below provides values that can give guidance to people when making decision on how to make their water more desirable for every day usage.

MANGANESE

Newer evidence suggests that long-term consumption of manganese may lead to health problems.

Manganese Fact Sheet

Arsenic 

Arsenic levels should be 0.010 mg/L, or 10 micrograms per liter (µg/L), or less. This MCL is based on the average person consuming 2 liters of water a day for a lifetime. Long term exposure to drinking water with arsenic levels higher than 10 µg/L increases your risk for chronic health issues like cancer.

Arsenic Fact Sheet